Journal articles on the topic 'The Bank of the Energy experimental platform'
To see the other types of publications on this topic, follow the link: The Bank of the Energy experimental platform.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'The Bank of the Energy experimental platform.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Zhang, Wei, Shizhen Li, Yanjun Liu, Detang Li, and Qin He. "Optimal Control for Hydraulic Cylinder Tracking Displacement of Wave Energy Experimental Platform." Energies 13, no. 11 (June 4, 2020): 2876. http://dx.doi.org/10.3390/en13112876.
Abstract:
The wave energy converter captures the wave power by buoy’s heaving motion, transfers it by hydraulic system, and converts it into the electric power by generator. The hydraulic conversion system plays an important role that can realize the effective regulation of the output power. In order to develop the working characteristics of the hydraulic transmission system, a new wave energy experimental platform was devised. The platform adopts the matching design mode of the driving oil cylinder and the driven oil cylinder. The active hydraulic cylinder and the clump weight can simulate the movement of the oscillating float under certain sea conditions, and the driven oil cylinder realizes the conversion and the output of wave energy. In order to improve the operation accuracy of the active hydraulic cylinder, the control strategy of the active hydraulic cylinder was studied. An adaptive sliding mode control strategy based on the back-stepping method was proposed to overcome the influence of the parameter uncertainty in state equation. The adaptive law was designed by Lyapunov criterion to ensure the stability and the convergence of the closed-loop system. The proposed control strategy was verified and compared with proportional integral derivative control strategy through the concrete experiment, which shows the rapidity and the stability of it. The hydraulic transmission system of wave energy converter was developed; at the same time, the characteristics of hydraulic regulation under different working conditions were summarized through experiments. The results of the research could be the guidance for the power control design.
2
Parada-Salado, Juan-Gerardo, Luis-Fernando Gaona-Cárdenas, Martín-Antonio Rodríguez-Licea, and Francisco-Javier Pérez-Pinal. "Harvesting in electric vehicles: combining multiple power tracking and fuel-cells." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 5 (October 1, 2020): 5058. http://dx.doi.org/10.11591/ijece.v10i5.pp5058-5073.
Abstract:
Exploitation of green energy sources is essential to diminish the deterioration of our environment. The energy harvesting, represents an alternative to achieve greater range in electric and hybrid vehicles. An energy management strategy (EMS) must be optimized to obtain the best benefits in such vehicles, which is not a trivial task. If harvesting or energy recovery devices are added, the EMS becomes a dual-purpose algorithm: minimizing fuel consumption and maximizing energy harvest through maximum
power point tracking (MPPT) controllers. Known studies consider separate EMS, one for traction and another for regenerative braking, without considering harvest devices such as solar panels, regenerative suspension, thermal generators, among others. Furthermore, the electronic power converters used, are not designed to handle such unequal power levels. In this article, an electronic platform to include multiple energy harvesting devices in a fuel-cell hybrid electric vehicle, was presented together with a multiple MPPT-EMS. The EMS is easily implementable, and considers quasiconstant cell energy extraction and filtering of current transients to the battery bank ensuring the longevity of the devices. A new mathematical model of the platform, a closed loop stability analysis, and numerical and Hardware-in-the-Loop (HIL) validations were presented. Some experimental validation results were also provided.
3
Kakuya, Hiromu, Takashi Shiraishi, Shigeo Yoshida, Tomoaki Utsunomiya, and Iku Sato. "Experimental results of floating platform vibration control with mode change function using full-scale spar-type floating offshore wind turbine." Wind Engineering 42, no. 3 (October 30, 2017): 230–42. http://dx.doi.org/10.1177/0309524x17737336.
Abstract:
Floating offshore wind turbines have great potential for harvesting renewable energy sources since offshore wind is stronger and more stable than onshore wind. The foundations of floating offshore wind turbines are not rigidly fixed and it leads to vibration of the floating platform pitch angle. This vibration is caused by fast blade pitch angle motions of variable speed control for controlling rotor speed at rated values. This study proposes a control method to address this vibration, floating platform vibration control. This method extracts a natural frequency component of the vibration from the floating platform pitch angle signal by a band pass filter and controls the blade pitch angle on the basis of proportional–derivative control. Its key characteristic is changing control modes in accordance with electrical power. Experiments using a full-scale spar-type floating offshore wind turbine were performed, and results show that the proposed floating platform vibration control can suppress the vibration of floating platform pitch angle.
4
Huo, Fali, Hongkun Yang, Zhi Yao, Kang An, and Sheng Xu. "Study on Slamming Pressure Characteristics of Platform under Freak Wave." Journal of Marine Science and Engineering 9, no. 11 (November 13, 2021): 1266. http://dx.doi.org/10.3390/jmse9111266.
Abstract:
Freak waves have great peak energy, short duration, great contingency, and strong nonlinear characteristics, and can cause severe damage to ships and marine structures. In this study, numerical simulations in conjunction with experimental tests are applied to study air gap response and wave slamming loads of a semi-submersible offshore platform under a freak wave. A three-dimensional wave tank, which is created based on the computational fluid dynamics (CFD) method, is applied to study the hydrodynamic responses of a semi-submersible platform. The numerical model of the tank and offshore platform system are checked according to the experimental results. A typical freak wave is modelled in numerical wave tanks by the linear superposition method, and its significant wave height is 13.03 m. It is found that the freak wave is closely associated with the wave slamming. The appearance of the freak wave gives rise to a negative air, gap which appears on the side of the back wave surface at the bottom of the deck box, and considerable slamming pressure is generated. Furthermore, the wave run up at the junction of the column and the buoyancy tank is also seen due to the freak wave.
5
Li, Pengfei, Yongying Jiang, and Jiawei Xiang. "Experimental Investigation for Fault Diagnosis Based on a Hybrid Approach Using Wavelet Packet and Support Vector Classification." Scientific World Journal 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/145807.
Abstract:
To deal with the difficulty to obtain a large number of fault samples under the practical condition for mechanical fault diagnosis, a hybrid method that combined wavelet packet decomposition and support vector classification (SVC) is proposed. The wavelet packet is employed to decompose the vibration signal to obtain the energy ratio in each frequency band. Taking energy ratios as feature vectors, the pattern recognition results are obtained by the SVC. The rolling bearing and gear fault diagnostic results of the typical experimental platform show that the present approach is robust to noise and has higher classification accuracy and, thus, provides a better way to diagnose mechanical faults under the condition of small fault samples.
6
Guan, Shaohua, Xiaocun Guan, Baoqi Wu, and Jingbin Shi. "Analysis of the Influence of System Parameters on Launch Performance of Electromagnetic Induction Coil Launcher." Energies 15, no. 20 (October 21, 2022): 7803. http://dx.doi.org/10.3390/en15207803.
Abstract:
The influence of electromagnetic induction coil launcher (EICL) system parameters on the launch performance was analyzed, and a method for measuring the launch performance of an EICL system with a muzzle velocity and energy conversion efficiency was proposed. The EICL system mainly includes a pulse power supply and launcher. The parameters of the pulse power supply mainly include the discharge voltage and the capacitance value of the capacitor bank. The structural parameters of the launcher mainly include the bore size of the launcher, the air gap length between the armature and the drive coil, the length and width of the drive coil, and the trigger position of the armature. Change in single or multiple parameters in the launch system will influence the launch performance. The influence of single or multiple parameters on the launch performance was summarized, and the physical law as analyzed. The influence law of the EICL system parameters on the launch performance was obtained, which lays a theoretical foundation for the optimization design of EICL. Finally, experimental verification was carried out by a single-stage test platform.
7
Zhou, Jing Hua, Peng Zeng, and Xiao Wei Zhang. "Full Power Experiment Method of Single-Phase PWM Back-to-Back Converter." Applied Mechanics and Materials 577 (July 2014): 488–93. http://dx.doi.org/10.4028/www.scientific.net/amm.577.488.
Abstract:
Based on the single-phase H-H power unit topology in the novel co-phase power supply system, with the back-to-back grid-connected operation method, this paper aimed at solving the problem that in experiment, system capacity constraints caused the failure to achieve unit full power output and proposed the strategy of rectifier voltage, current double closed loop and full disturbance feed-forward control. Finally, based on the digital signal processor (DSP) and complex programmable logic device (CPLD), this study constructed a hardware platform of the power unit control system. Experimental results show that the system is stable, achieving two-way flow of energy.
8
Wang, Dong Yun, Wen Zhi Zhang, Wei Ping Lu, and J. W. Du. "Application of Wavelet Packet Transform for Detection of Ball Bearing Race Fault." Materials Science Forum 626-627 (August 2009): 511–16. http://dx.doi.org/10.4028/www.scientific.net/msf.626-627.511.
Abstract:
In this study, a fault diagnosis system is proposed for rolling ball bearing race using wavelet packet transform(WPT) and artificial neural network(ANN)technique. Vibration signal from ball bearings having defects on inner race and outer race is considered and the extraction method of feature vector based on wavelet packet transform with frequency band energy is used. The vibration signal is decomposed into the individual frequency bands. The variations of the signal energy in these bands reflect the different fault locations. Further, the artificial neural network is proposed to develop the diagnostic rules of the data base in the present fault identification system. The experimental work is performed to evaluate the effect of fault diagnosis in a rolling ball bearing platform under different fault conditions. The experimental results indicate the effectiveness of the proposed method in fault bearing identification.
9
Tian, Xiao-chao, Jin-long Liu, Jun Hou, Hou-jun Gai, Jie Yang, Zhen-wen Sun, and Xia Liu. "Study of Polyvinylidene Fluoride Thin Film Power Generation Performance Based on Human Foot Movement." Journal of Nanoelectronics and Optoelectronics 17, no. 11 (November 1, 2022): 1417–25. http://dx.doi.org/10.1166/jno.2022.3331.
Abstract:
In order to find the programs that can be generated at low frequency, a scheme of using (polyvinylidene fluoride) piezoelectric film to collect the energy of human foot movement is proposed, and related theoretical analysis and experimental studies are conducted. The solution is capable of energy harvesting during low-frequency walking to provide power for wearable microelectronic devices. First, a system dynamics model was built to analyze the kinematics of the foot, and then COMSOL Multiphysics simulation software was used to simulate the vibration mode, stress–strain, and output voltage of the piezoelectric film. Finally, the experimental platform was built for experimental testing. The experimental results show that when the PVDF piezoelectric film on the back of the human foot is deformed, the output power will vary in a certain range. When the thickness of the piezoelectric film is 122 μm and the bending amplitude is 60°, the maximum output voltage in the experiment is 25.2 V, the output current is 0.0783 mA and the output power is 1.981 mW. The experimental results verify the feasibility of the scheme design and provide a new solution for powering electronic components.
10
Mori, Ryo, Kefeng Wang, Takahiro Morimoto, Samuel Ciocys, Jonathan D. Denlinger, Johnpierre Paglione, and Alessandra Lanzara. "Observation of a Flat and Extended Surface State in a Topological Semimetal." Materials 15, no. 8 (April 8, 2022): 2744. http://dx.doi.org/10.3390/ma15082744.
Abstract:
A flat band structure in momentum space is considered key for the realization of novel phenomena. A topological flat band, also known as a drumhead state, is an ideal platform to drive new exotic topological quantum phases. Using angle-resolved photoemission spectroscopy experiments, we reveal the emergence of a highly localized surface state in a topological semimetal BaAl4 and provide its full energy and momentum space topology. We find that the observed surface state is localized in momentum, inside a square-shaped bulk Dirac nodal loop, and in energy, leading to a flat band and a peak in the density of state. These results imply this class of materials as an experimental realization of drumhead surface states and provide an important reference for future studies of the fundamental physics of correlated quantum effects in topological materials.
11
Xu, Guang-Hui. "Dynamic Parameter Optimization and Experimental Study of Tuned Slab Damper on Metro Systems." Shock and Vibration 2019 (February 17, 2019): 1–14. http://dx.doi.org/10.1155/2019/1236827.
Abstract:
With the increase of axle weight and speed, the interaction between vehicles and the track becomes more and more intense, and the problem of wheel-rail dynamic action is more serious. In order to reduce the low-frequency vibration caused by train operation, a three-layer elastic track damping structure is proposed. The complex method is used to optimize the dynamic parameters, structural patterns, and coupling relations of the track structure, which allows multiple elastic units to work in harmony with each other to achieve the effects of absorbing vibration energy and reducing vibration transmission. Finally, a real size model experimental platform is set up to verify the dynamic parameter optimization results. The results show that the vertical mode of the main track system of the coupling-tuned slab damper-floating slab is 26.898 Hz close to the train excitation frequency, and the corresponding equivalent mass is 6074.53 kg. The amplitude of the vibration components in the 20∼40 Hz band can be reduced to 41.8% by using the complex method. The maximum insertion loss is about 10 dB, and the vibration of low-frequency band is not amplified.
12
Yang, Jianwei, Chang Liu, Qitong Xu, and Jinyi Tai. "Acoustic Emission Signal Fault Diagnosis Based on Compressed Sensing for RV Reducer." Sensors 22, no. 7 (March 30, 2022): 2641. http://dx.doi.org/10.3390/s22072641.
Abstract:
The rotate vector (RV) reducer has a complex structure and highly coupled internal components. Acoustic emission (AE) signal, which is more sensitive to a weak fault, is selected for fault diagnosis of the RV reducer. The high sampling frequency and big data are the challenges for AE signal store and analysis. This study combines compressed sensing (CS) and convolutional neural networks. As a result, data redundancy is significantly reduced while retaining most of the information, and the analysis efficiency is improved. Firstly, the time-domain AE signal was projected into the compression domain to obtain the compression signal; then, the wavelet packet decomposition in the compressed domain was performed to obtain the information of each frequency band. Next, the frequency band information was sent into the input layer of the multi-channel convolutional layer, and the energy pooling layer mines the energy characteristics of each frequency band. Finally, the softmax classifier was used to classify and predict different fault types of RV reducers. The self-fabricated RV reducer experimental platform was used to verify the proposed method. The experimental results show that the proposed method can effectively extract the fault features in the AE signal of the RV reducer, improve the efficiency of signal processing and analysis, and achieve the accurate classification of RV reducer faults.
13
Li, Yan, Dezhi Yang, Wenyu Yang, Zhisheng Wu, and Cuirong Liu. "Multiphysics Numerical Simulation of the Transient Forming Mechanism of Magnetic Pulse Welding." Metals 12, no. 7 (July 6, 2022): 1149. http://dx.doi.org/10.3390/met12071149.
Abstract:
Magnetic pulse welding (MPW) is widely used in the connection of dissimilar metals. The welding process involves the coupling of the electromagnetic field and structural field, which is a high-energy transient forming process. Based on the current experimental methods, it is difficult to capture the relevant data in the process of magnetic pulse welding, and the transient forming mechanism of magnetic pulse welding needs to be further studied. Taking the magnetic pulse welding of an Al-Mg sheet as an example, based on the Ansoft Maxwell and ANSYS finite element simulation platform, the loose coupling method was used to analyze an electromagnetic field generated by the discharging capacitor bank and structural field of the Al-Mg sheet under the action of electromagnetic force. The discharge period of the magnetic pulse welding capacitor bank was 62 μs. The current direction in the aluminum sheet changed once half a cycle, and the direction of the electromagnetic force was always consistent with the Z-axis. Under the skin effect, the magnetic induction intensity on the lower surface of the aluminum sheet was the largest. At 16 μs, the induced current, electromagnetic force and magnetic induction intensity in the aluminum sheet reached the peak values, which were 7.89 A/m2, 4.58 N/m3 and 12.6 T, respectively. The maximum electromagnetic force and velocity in the structural field were 2400 KN and 300 m/s. The structure field simulation reproduces the transient forming process of magnetic pulse welding, and clarifies the formation mechanism of the “intermediate zone rebound uncomposite zone-welding bonding zone-unbound zone”. Based on the numerical simulation technology, the research on the transient forming mechanism of magnetic pulse welding under multiphysics simulations can promote the development and application of magnetic pulse welding technology and better guide engineering practices.
14
Xu, Dachuan, Yunsong Gu, Xinglong Gao, Zebin Ren, and Jingxiang Chen. "Experimental Investigation on Boundary Layer Control and Pressure Performance for Low Reynolds Flow with Chemical Reaction." Applied Sciences 13, no. 20 (October 16, 2023): 11335. http://dx.doi.org/10.3390/app132011335.
Abstract:
This study examines boundary layer control and pressure recovery in low Reynolds number supersonic flow with chemical reactions in a chemical laser system. Our work prescribes a novel boundary layer control method for the optical cavity of a chemical laser system, and a design of a supersonic diffuser is compared and proposed to make a stable flow for the system. The flow characteristics of a low Reynolds number and internal reaction heat release were analyzed. Three types of experimental pieces were designed to passively control the boundary layer in the optical cavity. An active booster-type supersonic diffuser is proposed to study the pressure recovery problem of a low Reynolds number and chemical reaction supersonic flow generated by an optical cavity. A supersonic chemical reaction platform (SCRP) was established to conduct experimental research on boundary layer control and docking the active booster supersonic diffuser with the SCRP. The experimental results indicate that increasing the boundary layer pumping capacity within a certain range can reduce both the boundary layer thickness and the pressure on the optical cavity while simultaneously enhancing the SCRP energy power. The supersonic diffuser based on active gas pressurization can create the necessary conditions for the normal chemical reaction and improve the ability of the SCRP to resist high back pressure and airflow disturbance. Moreover, the chemical reaction energy release was full and stable with the docking of supersonic diffuser test pieces, resulting in energy power increases, which could be a significant improvement for the design of chemical laser systems.
15
Song, Dawei, Shiqian Wang, Li Di, Weijian Zhang, Qian Wang, and Jing V. Wang. "Lithium-Ion Battery Life Prediction Method under Thermal Gradient Conditions." Energies 16, no. 2 (January 9, 2023): 767. http://dx.doi.org/10.3390/en16020767.
Abstract:
Thermal gradient is inevitable in a lithium-ion battery pack because of uneven heat generation and dissipation, which will affect battery aging. In this paper, an experimental platform for a battery cycle aging test is built that can simulate practical thermal gradient conditions. Experimental results indicate a high nonlinear degree of battery degradation. Considering the nonlinearity of Li-ion batteries aging, the extreme learning machine (ELM), which has good learning and fitting ability for highly nonlinear, highly nonstationary, and time-varying data, is adopted for prediction. A battery life prediction model based on the sparrow search algorithm (SSA) is proposed in this paper to optimize the random weights and bias of the ELM network and verified by experimental data. The results show that compared with traditional ELM and back-propagation neural networks, the prediction results of ELM optimized by SSA have lower mean absolute error percentages and root mean square errors, indicating that the SSA-ELM model has higher prediction accuracy and better stability and has obvious advantages in processing data with a high nonlinear degree.
16
USMAN, O. L., O. FOLORUNSO, and O. B. ALABA. "ELECTRICITY CONSUMPTION PREDICTION SYSTEM USING A RADIAL BASIS FUNCTION NEURAL NETWORK." Journal of Natural Sciences Engineering and Technology 15, no. 1 (November 22, 2017): 1–20. http://dx.doi.org/10.51406/jnset.v15i1.1660.
Abstract:
The observed poor quality of service being experienced in the power sector of Nigeria economy has been traced to non-availability of adequate model that can handle the inconsistencies associated with traditional statistical models for predicting consumers’ electricity need, so as to bridge the gap between the demand and supply of the energy. This research presents Electricity Consumption Prediction System (ECPS) based on the principle of radial basis function neural network to predict the country’s electricity consumption using the historical data sourced from Central Bank of Nigeria (CBN) annual statistical bulletin. The entire datasets used in the study were divided into train, validation and test sets in the ratio of 13:3:4. By the above, 65% of the entire data were used for the training, 15% for validation and 20% for testing. The train data was presented to the constructed models to approximate the function that maps the input patterns to some known target values. The models were also used to simulate both validation and the test datasets as case data on the consistency of results obtained from the training session through the train data. Experimental results showed that RBF network model performs better than equivalent Backpropagation (BP) network models that were compared with it and provides the best platform for developing a forecast system.
17
Real-Ramirez, Cesar Augusto, Ignacio Carvajal-Mariscal, Jesus Gonzalez-Trejo, Ruslan Gabbasov, Jose Raul Miranda-Tello, and Jaime Klapp. "Numerical Simulations of the Flow Dynamics in a Tube with Inclined Fins Using Open-Source Software." Fluids 7, no. 8 (August 18, 2022): 282. http://dx.doi.org/10.3390/fluids7080282.
Abstract:
Finned tubes increase the convective heat transfer in heat exchangers, reducing the total energy consumption of integrated industrial processes. Due to its stability and robustness, Computational Fluid Dynamics (CFD) commercial software is generally utilized for analyzing complex systems; however, its licensing is expensive. Nowadays, open-source software is a viable substitute for proprietary software. This work presents a CFD analysis of the hydrodynamics of a finned tube using the OpenFOAM and SALOME Meca platforms. The results are compared with experimental data and CFD using the commercial software Fluent, both previously reported in the open literature. This work studies the fluid flow pattern around a tube with six 45-degree-angled fins, and the working fluid, air, is considered as an incompressible fluid. Special attention is paid to calculating the pressure coefficient distribution for the internal and external surfaces of the inclined fins. Open-source platforms allow researchers to visualize how the airflow interacts with the cylinder and the fin surfaces to form a fluid structure, formerly known as a horseshoe vortex system. The findings of the analysis of flow dynamics in the channel between inclined fins and in the wake help explain the results obtained in experimental tests and are relevant for the configuration of a bank of tubes with inclined fins.
18
Yang, Tie, Wenlong Lü, Xingwen Tan, Zeying Zhang, Gang Zhang, and Zhimin Wu. "Ideal quadratic fermionic point state with multiple band degeneracy." Applied Physics Letters 122, no. 2 (January 9, 2023): 023101. http://dx.doi.org/10.1063/5.0131701.
Abstract:
As the study of topological states witnessed rapid progress and fast development, the current research has been expanded from conventional linear dispersion into high order conditions. In comparison with the linear type, high order topological elements feature multiple exotic properties, such as large topological charge, peculiar Berry phase, and chiral surface states, which could lead to the finding of other new physics. In this study, we present a realistic material candidate hosting an ideal quadratic fermionic point state with multiple band degeneracy. Based on first principles calculation and effective model argument, the origin of the quadratic order is analyzed, and its dispersion conditions are examined. Due to the clean band structure, prominent surface states are observed and they exhibit both large energy variation and broad spatial distribution. These beneficial features are very advantageous for future experimental investigations. This work can significantly enhance the research on high order topological states and, in particular, the proposed material can provide an effective platform for quadratic fermionic point states.
19
Chen, Yin, Zhenli Tang, Xiaofeng Weng, Min He, Sheng Zhou, Ziqiang Liu, and Tao Jin. "A Diagnostic Method for Open-Circuit Faults in DC Charging Stations Based on Improved S-Transform and LightGBM." Energies 17, no. 2 (January 13, 2024): 404. http://dx.doi.org/10.3390/en17020404.
Abstract:
The open-circuit fault in electric vehicle charging stations not only impacts the power quality of the electrical grid but also poses a threat to charging safety. Therefore, it is of great significance to study open-circuit fault diagnosis for ensuring the safe and stable operation of power grids and reducing the maintenance cost of charging stations. This paper addresses the multidimensional characteristics of open-circuit fault signals in charging stations and proposes a fault diagnosis method based on an improved S-transform and LightGBM. The method first utilizes improved incomplete S-transform and principal component analysis (PCA) to extract features of front- and back-stage faults separately. Subsequently, LightGBM is employed to classify the extracted features, ultimately achieving fault diagnosis. Simulation results demonstrate the method’s effectiveness in feature extraction, achieving an average diagnostic accuracy of 97.04% on the test dataset, along with notable noise resistance and real-time performance. Additionally, we designed an experimental platform for diagnosing open-circuit faults in DC charging station and collected experimental fault data. The results further validate the effectiveness of the proposed method.
20
Zheng, Youzhuo, Long Hua, Yekui Yang, Chun Li, Chaoyi Luo, Zihong Song, Xingwu Yang, and Haibo Feng. "Stability Enhancement Method of Standalone Modular Multilevel Converters Based on Impedance Reshaping." Energies 17, no. 4 (February 14, 2024): 895. http://dx.doi.org/10.3390/en17040895.
Abstract:
Modular multilevel converters (MMCs) are susceptible to subsynchronous oscillations (SSOs) caused by impedance interactions in the power line. Current research into the stability of MMCs focuses mainly on voltage feed-forward control, while the effect of current feed-forward control is neglected. This paper proposes a current feed-forward compensation method based on impedance reshaping for standalone MMCs. Initially, an impedance model was developed to identify the stability risks caused by the interaction between the MMC and power line impedance. The proposed method feeds the current compensation signal into the modulation circuit, thereby improving the control signal and suppressing the impedance interaction between the MMC and the power line. The analysis of the harmonic state space (HSS) method verifies that the proposed approach effectively reduces the negative damping region in the frequency band where the SSO is located. Additionally, the impedance frequency scanning method confirms the accuracy of impedance modeling. Using the MATLAB/Simulink platform and StarSim HIL hardware-in-the-loop experimental platform, the SSO phenomenon of the MMC is simulated, and the results show that the proposed method can effectively suppress harmonic currents during SSO, which verifies the accuracy of the stability analysis and the feasibility of the proposed method.
21
Jiang, Feng, Fan Yang, Songjun Sun, and Kai Yang. "Static-Errorless Rotor Position Estimation Method Based on Linear Extended State Observer for IPMSM Sensorless Drives." Energies 15, no. 5 (March 7, 2022): 1943. http://dx.doi.org/10.3390/en15051943.
Abstract:
This article presents a static-errorless rotor position estimation method based on the linear extended state observer (LESO) for interior permanent magnet synchronous motor (IPMSM) drives. Two second-order LESOs are utilized to estimate the α-β axis back-EMFs. A third-order LESO is incorporated into the quadrature phase-locked loop (QPLL) to achieve a high robustness of position tracking against external disturbance. In addition, considering that the nonideal back-EMF will bring DC and harmonic fluctuation errors to the estimated position, an enhanced LESO-based QPLL with static-errorless rotor position estimation is proposed. On the one hand, the DC position esti mation error caused by the phase lag of the back-EMF estimator is analyzed and compensated. On the other hand, to suppress the position harmonic fluctuations induced from the nonsinusoidal back-EMFs, a second-order generalize integrator (SOGI) is embedded in the feedforward path of the LESO-based QPLL. The experimental results on the 1.0 kW IPMSM drive platform show that, compared to the conventional method, the proposed method can achieve better position estimation performance both in steady-state operation and in transient-state operation.
22
Wang, Haiyan, Ji Ma, Feng Du, Gongda Wang, Quan Zhang, and Xiaoshen Li. "Research on the Attenuation Characteristics of AE Signals of Marble and Granite Stone." Advances in Civil Engineering 2020 (December 24, 2020): 1–19. http://dx.doi.org/10.1155/2020/6680347.
Abstract:
When an underground rock is deformed or fractured by an external or internal force, the energy will be released in the form of an elastic wave, which is known as the acoustic emission (AE) phenomenon. Extracting useful information from complex AE signals for the early warning of fracture characteristics and the damage monitoring of rock materials is of great significance for the prevention and control of dynamic disasters in coal mines. In this work, by taking rod-shaped rocks and plate-shaped rocks with different lithologies as the research objects, the elastic wave propagation characteristics of the rod-shaped rocks and plate-shaped rocks were studied by a self-constructed experimental platform. The results demonstrate that the elastic wave attenuation of the rod-shaped marble was the fastest, and the elastic wave attenuation characteristics of the three groups of rod-shaped granite were similar. The attenuation of the P-wave preceded that of the S-wave. With the increase in the propagation distance, the amplitude of the large-scale plate-shaped rock showed an approximate exponential attenuation characteristic. The elastic wave attenuation of the plate-shaped granite in the 0° direction was stronger than that of the plate-shaped marble, and it was weaker than that of the plate-shaped marble in the 45° and 90° directions. The energy changes in marble were more severe than those in granite. The main dominant energy of the AE signals of experimental rock was concentrated in the range of 0–176.78 kHz, and part of the residual energy was located in the high-frequency band of 282.25–352.56 kHz.
23
Padilla-Medina, Alfredo, Francisco Perez-Pinal, Alonso Jimenez-Garibay, Antonio Vazquez-Lopez, and Juan Martinez-Nolasco. "Design and Implementation of an Energy-Management System for a Grid-Connected Residential DC Microgrid." Energies 13, no. 16 (August 6, 2020): 4074. http://dx.doi.org/10.3390/en13164074.
Abstract:
The design and implementation of an energy-management system (EMS) applied to a residential direct current microgrid (DC-µG) is presented in this work. The proposed residential DC-µG is designed to provide a maximum power of one kilowatt by using two photovoltaic arrays (PAs) of 500 W, a battery bank (BB) of 120 V–115 Ah, a supercapacitor module of 0.230 F and a bidirectional DC–AC converter linked to the AC main grid (MG). The EMS works as a centralized manager and it defines the working operation mode for each section of the DC-µG. The operation modes are based on: (1) the DC-link bus voltage, (2) the generated or demanded power to each section of the DC-µG and (3) the BB’s state of charge. The proposed EMS—during the several working operation modes and at the same time—can obtain the maximum energy from the PAs, reduce the energy consumption from the main grid and keep the DC-link bus voltage inside a range of 190 V ± 5%. The EMS and local controllers are implemented by using LabVIEW and NI myRIO-1900 platforms. Moreover, experimental results during connection and disconnection of each DC-µG sections and different on-the-fly transitions are reported, these results focus on the behavior of the DC bus, which shows the DC bus robustness and stability. The robustness of the DC-µG is demonstrated by maintaining a balance of energy between the sources and loads connected to the DC bus under different scenarios.
24
Strickland, William M., Mehdi Hatefipour, Dylan Langone, S. M. Farzaneh, and Javad Shabani. "Controlling Fermi level pinning in near-surface InAs quantum wells." Applied Physics Letters 121, no. 9 (August 29, 2022): 092104. http://dx.doi.org/10.1063/5.0101579.
Abstract:
Hybrid superconductor–semiconductor heterostructures are a promising platform for quantum devices based on mesoscopic and topological superconductivity. In these structures, a semiconductor must be in close proximity to a superconductor and form an Ohmic contact. This can be accommodated in narrow bandgap semiconductors, such as InAs, where the surface Fermi level is positioned close to the conduction band. In this work, we study the structural properties of near-surface InAs quantum wells and find that surface morphology is closely connected to low-temperature transport, where electron mobility is highly sensitive to the growth temperature of the underlying graded buffer layer. By introducing an In0.81Al0.19As capping layer, we show that we change the surface Fermi level pinning of the In0.81Al0.19As thin film as compared to the In0.81Ga0.19As, giving rise to a tuning of the Fermi level in the InAs layer. Experimental measurements show a strong agreement with Schrödinger–Poisson calculations of the electron density, suggesting the conduction band energy of the In0.81Ga0.19As and In0.81Al0.19As surface is pinned to 40 and 309 meV above the Fermi level, respectively.
25
Liu, Tao, Chaoyang Shen, Jingfa Lei, Zhiqiang Yin, Hong Sun, and Jingxiong Wu. "Magnetic-Acoustic Feature Extraction and Damage Fusion Evaluation of 45 Steel Specimens during Fatigue Process for Remanufacturing." Advances in Materials Science and Engineering 2022 (August 12, 2022): 1–13. http://dx.doi.org/10.1155/2022/1966794.
Abstract:
To clarify the changes of the magnetic-acoustic features of 45 steel specimens during fatigue damage, an experimental platform was built to carry out magnetic memory and acoustic emission detection. The magnetic memory and acoustic emission signals of specimens in different damage states were collected, and the multi-scale entropy characteristics of magnetic memory signals, as well as the wavelet packet energy spectrum and singularity index characteristics of acoustic emission signals, were further extracted. A magnetic-acoustic feature fusion and damage assessment model was constructed by using Naive Bayes method. Results show that the average value of multi-scale entropy of normal magnetic field intensity Hp (y) increases gradually with the increase of fatigue cycles, and the average value of multi-scale entropy of magnetic field intensity gradient K gradually decreases. The cumulative ringing count and energy spectrum (proportion of frequency band 1) of acoustic emission signals decrease with the increase of fatigue cycles, while the amplitude singularity index gradually increases. The established model has high evaluation accuracy, and the conclusions of this paper can provide basic methods and data support for fatigue damage evaluation of remanufactured components.
26
Chikoidze, Ekaterine, Corinne Sartel, Hayate Yamano, Zeyu Chi, Guillaume Bouchez, François Jomard, Vincent Sallet, et al. "Electrical properties of p-type Zn:Ga2O3 thin films." Journal of Vacuum Science & Technology A 40, no. 4 (July 2022): 043401. http://dx.doi.org/10.1116/6.0001766.
Abstract:
Ultra-wide bandgap gallium oxide (∼5 eV) has emerged as a novel semiconductor platform for extending the current limits of power electronics and deep ultraviolet optoelectronics at a predicted fraction of cost. Finding effective acceptor dopant for gallium oxide is a hot issue. One element that quite often is considered as a potential candidate is zinc. A number of experimental works have reported the signature of Zn-acceptor, but the direct evidence of hole conductivity was missing. In this work, p-type Zn-doped Ga2O3 thin films were grown by the metal-organic chemical vapour deposition technique on sapphire substrates. By high-temperature Hall effect measurements, Zn related acceptor level ionization energy as 0.77 eV above the valence band maximum was determined. Additionally, we have carried out the simulation study regarding the application of the Zn:Ga2O3 semi-insulating material, to be used as a guard ring for improving the high voltage performance of the Schottky diode structure.
27
He, Zhi Yong, Qing Hua He, and Shang Hong He. "The Research of Hydraulic System Anti-Vibration and Noise Reduction." Advanced Materials Research 308-310 (August 2011): 1492–96. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.1492.
Abstract:
In this paper, the hazards of hydraulic pipeline system vibration and noise were introduced, the causes of vibration and noise of hydraulic pump circuit were analyzed and its frequency components were discussed. A wave filter of structure resonator based on Fluid-structure coupling vibration is designed and manufactured according to the principle of gas muffler. The differential equation of rectangular plate transverse free vibration characteristics was established, the coupling vibration resonance frequency of filter structure vibration body was obtained about 218Hz by solving differential equation according to the Rayleigh - Ritz method. The hydraulic pump flow pulsation frequency was adjusted respectively 215.55 Hz and 197.4 Hz through frequency conversion motor adjustment, and then comparative experiments were tested on the hydraulic system pressure fluctuation test experimental platform. Experiments show that, when the inherent resonance frequency of filter structural vibration body was approached the hydraulic system frequency, system pulse energy would be effectively attenuated, system pressure fluctuations would be greatly reduced and pulse rate was dropped from 3.65％to 0.28％. The attenuation of the effects of pressure pulsations was validated through experimental research, but also its defects that the filter has frequency selectivity and band narrow were founded The later research direction was put forward and new technology for hydraulic system vibration control was provided.
28
Zhang, Jian. "Flow characteristics of a hydraulic cone-throttle valve during cavitation." Industrial Lubrication and Tribology 71, no. 10 (December 2, 2019): 1186–93. http://dx.doi.org/10.1108/ilt-10-2018-0394.
Abstract:
Purpose This paper aims to resolve the cavitation problem encountered in cone throttle valves concerning fluid flow performance and pitting from cavitation luminescence, the author studied the flow field within a cone throttle valve set with various valve openings, inlet pressures and outlet back pressures. Design/methodology/approach The flow and cavitation distribution in the valve under different pressure conditions were obtained in simulations. To confirm these results experimentally, a hydraulic cavitation platform was constructed. The valve was made of polymethyl methacrylate material with high transparency to observe the cavitation directly, as well as cavitation luminescence. The flow characteristics of this valve were measured under various working conditions. Findings With increasing cavitation strength, a reduction in cavitation on the throttle capacity was more evident. Increasing the back pressure and reducing the working pressure of the valve appropriately improves the flow capacity of the valve, which subsequently improves the performance of the valve. The cavitation luminescence is also linearly related to cavitation intensity. That is, the stronger the flow capacity of the valve, the less likely the luminescence is produced. Moreover, a stronger luminescence intensity worsens the flow performance of the valve. Research limitations/implications Owing to the limitation of experimental means and lack of research on bubble shape, the subsequent research will complement this aspect. Practical implications With a view to providing theoretical and experimental support, cavitation luminescence is also studied to gain a deeper understanding of the cavitation mechanism in hydraulic valves. Originality/value The innovation of this paper is to study the cavitation luminescence in the hydraulic system.
29
Cao, Fuqiang, Quntao An, Jianqiu Zhang, Mengji Zhao, and Siwen Li. "Variable Weighting Coefficient of EMF-Based Enhanced Sliding Mode Observer for Sensorless PMSM Drives." Energies 15, no. 16 (August 18, 2022): 6001. http://dx.doi.org/10.3390/en15166001.
Abstract:
In the field of permanent magnet synchronous motor (PMSM) control, the sliding mode observer (SMO)-based sensorless control is widely used; however, the actual control input of the current observation function is asymmetric. It can lead to different velocities of the estimated currents approaching to the actual currents and will make the current and back EMF fluctuations more severe, and result in more skewed angle and speed estimates, especially at a lower carrier ratio. In response to the above problems, this paper proposes a variable weighting coefficient of an EMF-based sliding mode observer (VWC-SMO). Unlike the traditional sliding mode observers, the weighted sliding mode switching variables and their bandpass-filtered values are used as the input of the current observer in the VWC-SMO. Thereby, the asymmetry of the control input in the current observation function can be well-suppressed, and almost the same approaching velocity on the two sides of the sliding surface can be obtained. Therefore, chattering near the sliding surface can also be suppressed. The method is verified on a motor controller experimental platform, and the comparative results shows that the VWC-SMO can reduce chattering of the observed currents and mitigate back EMFs fluctuations and improve the dynamic and steady-state performance.
30
Kawasugi, Yoshitaka, Hikaru Masuda, Jiang Pu, Taishi Takenobu, Hiroshi M. Yamamoto, Reizo Kato, and Naoya Tajima. "Electric Double Layer Doping of Charge-Ordered Insulators α-(BEDT-TTF)2I3 and α-(BETS)2I3." Crystals 11, no. 7 (July 7, 2021): 791. http://dx.doi.org/10.3390/cryst11070791.
Abstract:
Field-effect transistors based on strongly correlated insulators are an excellent platform for studying the electronic phase transition and simultaneously developing phase transition transistors. Molecular conductors are suitable for phase transition transistors owing to the high tunability of the electronic states. Molecular Mott transistors show field-induced phase transitions including superconducting transitions. However, their application to charge-ordered insulators is limited. In this study, we fabricated electric double layer transistors based on quarter-filled charge-ordered insulators α-(BEDT-TTF)2I3 and α-(BETS)2I3. We observed ambipolar field effects in both compounds where both electron and hole doping (up to the order of 1013 cm−2) reduces the resistance by the band filling shift from the commensurate value. The maximum field-effect mobilities are approximately 10 and 55 cm2/Vs, and the gate-induced conductivities are 0.96 and 3.6 e2/h in α-(BEDT-TTF)2I3 and α-(BETS)2I3, respectively. However, gate-induced metallic conduction does not emerge. The gate voltage dependence of the activation energy in α-(BEDT-TTF)2I3 and the Hall resistance in α-(BETS)2I3 imply that the electric double layer doping in the present experimental setup induces hopping transport rather than band-like two-dimensional transport.
31
Karthikeyan, B., Palanisamy Ramasamy, M. Pandi Maharajan, N. Padmamalini, J. Sivakumar, Subhashree Choudhury, and George Fernandez Savari. "The Optimization of PEM Fuel-Cell Operating Parameters with the Design of a Multiport High-Gain DC–DC Converter for Hybrid Electric Vehicle Application." Sustainability 16, no. 2 (January 19, 2024): 872. http://dx.doi.org/10.3390/su16020872.
Abstract:
The fossil fuel crisis is a major concern across the globe, and fossil fuels are being exhausted day by day. It is essential to promptly change from fossil fuels to renewable energy resources for transportation applications as they make a major contribution to fossil fuel consumption. Among the available energy resources, a fuel cell is the most affordable for transportation applications because of such advantages as moderate operating temperature, high energy density, and scalable size. It is a challenging task to optimize PEMFC operating parameters for the enhancement of performance. This paper provides a detailed study on the optimization of PEMFC operating parameters using a multilayer feed-forward neural network, a genetic algorithm, and the design of a multiport high-gain DC–DC converter for hybrid electric vehicle application, which is capable of handling both a 6 kW PEMFC and an 80 AH 12 V heavy-duty battery. To trace the maximum power from the PEMFC, the most recent SFO-based MPPT control technique is implemented in this research work. Initially, a multilayer feed-forward neural network is trained using a back-propagation algorithm with experimental data. Then, the optimization phase is separately carried out in a neural-power software environment using a genetic algorithm (GA). The simulation study was carried out using the MATLAB/R2022a platform to verify the converter performance along with the SFO-based MPPT controller. To validate the real-time test bench results, a 0.2 kW prototype model was constructed in the laboratory, and the results were verified.
32
Yuan, Xiaoming, Yueqi Bi, Mingrui Hao, Qiang Ji, Zhigeng Liu, and Jiusheng Bao. "Research on Location Estimation for Coal Tunnel Vehicle Based on Ultra-Wide Band Equipment." Energies 15, no. 22 (November 15, 2022): 8524. http://dx.doi.org/10.3390/en15228524.
Abstract:
Because the road surfaces of the underground roadways in coal mines are slippery, uneven, with dust and water mist, and the noise and light illumination effects are significant, global positioning system (GPS) signals cannot be received, which seriously affects the ability of the odometer, optical camera and ultrasonic camera to collect data. Therefore, the underground positioning of coal mines is a difficult issue that restricts the intellectualization of underground transportation, especially for automatic robots and automatic driving vehicles. Ultra-wide band (UWB) positioning technology has low power consumption, high performance and good positioning effects in non-visual environments. It is widely used in coal mine underground equipment positioning and information transmission. In view of the above problems, this research uses the WLR-5A mining unmanned wheeled chassis experimental platform; uses two UWB receivers to infer the position and yaw information of the vehicle in the underground roadway through the method of differential mapping; and tests the vehicle on the double shift line and quarter turn line in the GAZEBO simulation environment and on the ground simulation roadway to simulate the vehicle meeting conditions and quarter turning conditions in the underground roadway. The positioning ability of the method in these two cases is tested. The simulation and test results show that the vehicle position and attitude information deduced by two UWB receivers through the differential mapping method can basically meet the requirements of underground environments when the vehicle is traveling at low speeds.
33
Zhang, Ya-Jie, Yan-Ju Wei, Huzaifa Jamil, and Sheng-Hua Liu. "Investigation of the Behaviors of Methanol Spray Impingement and Wall Wetting." Applied Sciences 12, no. 23 (November 30, 2022): 12263. http://dx.doi.org/10.3390/app122312263.
Abstract:
Port fuel injection is an important technical route in methanol engines. To obtain a theoretical basis for injector arrangement and injection strategy development in methanol engines, an optimal experimental platform based on diffuse back-illumination and the refractive index matching method (RIM) was designed and built in this study. The experiments on the behavior of low-pressure methanol spray-wall impingement and wall film were carried out and the influence of the three boundary conditions of spray distance (Dimp), wall temperature (Twall), and injection pressure (Pinj) were analyzed comprehensively. Results showed that with the increase of Dimp, the overall shape of spray before impinging the wall changed from conical to cylindrical. The impinging spray height Hi and impinging spray width Wi increased with the decrease of Dimp and the increase of Pinj. Adhesive fuel film mass Mf increased with the increase of Dimp due to the decrease of kinetic energy during wall impact. In addition, the increase of the wall temperature Twall reduced Mf due to evaporation, but when Twall reached 423 K, Mf rebounded due to the Leidenfrost effect. The results of this study are helpful to improve the accuracy of the numerical methanol engine model.
34
Wang, Zhiyuan, Chao Kang, Zongyang Zhang, and Jie Guo. "Research on continuous current characteristics and operating load characteristics of EGLA in UHVDC lines." Journal of Physics: Conference Series 2369, no. 1 (November 1, 2022): 012047. http://dx.doi.org/10.1088/1742-6596/2369/1/012047.
Abstract:
In order to ensure the safe and stable operation of UHVDC transmission system, line arresters with series gap (EGLA) are often installed on UHVDC lines in engineering. When the line is struck by strong lightning, the series gap of EGLA will be broken down and the lightning will flow through the SVU. After lightning flows, EGLA needs to cut off the continuous current in time and reliably to restore the high resistance state. Therefore, the research on the characteristics of continuous current and operating load of EGLA is related to the design and selection of EGLA parameters, which has important engineering significance. However, due to the lack of UHVDC experimental platform, the relevant research is less, resulting in the lack of basis for determining SVU parameters. Based on the ±800 kV UHVDC transmission line from northern Shanxi to Nanjing in Jiangsu Province, this paper uses the method of control variables to simulate and study the characteristics of EGLA under different lightning strike modes, line positions and transmission capacities, and draws the conclusion that compared with back flashover on the tower, the peak value of EGLA under lightning shielding failure is smaller but the absorbed energy is larger, and the influence of transmission capacity is more obvious. When the lightning shielding failure on the middle tower of the line, the absorbed energy of EGLA is the largest and the continuous current is smaller.
35
Chen, Yujie, Juan Jiang, Haifeng Yang, Pavel Dudin, Alexey Barinov, Zhongkai Liu, Haihu Wen, Lexian Yang, and Yulin Chen. "Visualization of the electronic phase separation in superconducting KxFe2−ySe2." Nano Research 14, no. 3 (October 19, 2020): 823–28. http://dx.doi.org/10.1007/s12274-020-3119-8.
Abstract:
AbstractType-II iron-based superconductors (Fe-SCs), the alkali-metal-intercalated iron selenide AxFe2−ySe2 (A = K, Tl, Rb, etc.) with a superconducting transition temperature of 32 K, exhibit unique properties such as high Néel temperature, Fe-vacancies ordering, antiferromagnetically ordered insulating state in the phase diagram, and mesoscopic phase separation in the superconducting materials. In particular, the electronic and structural phase separation in these systems has attracted intensive attention since it provides a platform to unveil the insulating parent phase of type-II Fe-SCs that mimics the Mott parent phase in cuprates. In this work, we use spatial- and angle-resolved photoemission spectroscopy to study the electronic structure of superconducting KxFe2−ySe2. We observe clear electronic phase separation of KxFe2−ySe2 into metallic islands and insulating matrix, showing different K and Fe concentrations. While the metallic islands show strongly dispersive bands near the Fermi level, the insulating phase shows an energy gap up to 700 meV and a nearly flat band around 700 meV below the Fermi energy, consistent with previous experimental and theoretical results on the superconducting K1−xFe2Se2 (122 phase) and Fe-vacancy ordered K0.8Fe1.6Se2 (245 phase), respectively. Our results not only provide important insights into the mysterious composition of phase-separated superconducting and insulating phases of KxFe2−ySe2, but also present their intrinsic electronic structures, which will shed light on the comprehension of the unique physics in type-II Fe-SCs.
36
Darji, Ankit, and Divyang Pandya. "Fault diagnosis of SKF-6205 bearing with modified empirical mode decomposition." International Journal of Engineering, Science and Technology 13, no. 4 (May 30, 2022): 12–20. http://dx.doi.org/10.4314/ijest.v13i4.2.
Abstract:
Rolling element bearings are broadly used in the rotating machines to support static and dynamic loads. In this research, the advance signal processing techniques are use for processing of bearing fault signals. Experimental validation with genuine vibration signals calculated from bearings with seeded defects on bearing elements. The model-based fault diagnosis method has attempted to diagnose incipient fault detection and classification of bearing with data driven approach. Feature extraction technique has been developed with hybrid signal processing technique based on the band pass filter nature of Empirical mode decomposition (EMD), the resonant frequency bands have owed in specific mono component signals called Intrinsic Mode Functions (IMFs). Synchronized resonant frequency band (SRFB) is obtained on based of orthogonal real wavelet using spectral kurtosis. Biorthogonal 5.5 wavelet, a real wavelet has been selected as a suitable wavelet for WPT based on “Maximum Relative Wavelet Energy” and “Maximum Energy-to-Shannon entropy ratio”. Three, Feature extraction techniques like continuous wavelet transform (CWT), wavelet packet transform (WPT) and modified Hilbert Huang Transforms (HHT) are compared on bases of their classification accuracy with different classification algorithm and filters. Various supervised classifiers have been compared through a common platform of Waikato Environment for Knowledge Analysis (WEKA) and concluded the k- nearest neighbour (KNN) as an effective available classifier for rolling element bearing. Further, asymmetric proximity function based KNN (APF-KNN) has out performs with modified feature selection criteria. Feature extraction through modified HHT and APFKNN has been future as a most effectual fault classification method. For testing any unknown data, simplified method has been demonstrated, which make the proposed data driven approach more realistic, faster and automated.
37
Kunz Cechinel, Alan, Carlos Eduardo Soares, Sergio Genilson Pfleger, Leonardo Luiz Gambalonga Alves De Oliveira, Ederson Américo de Andrade, Claudia Damo Bertoli, Carlos Roberto De Rolt, Edson Roberto De Pieri, Patricia Della Méa Plentz, and Juha Röning. "Mobile Robot + IoT: Project of Sustainable Technology for Sanitizing Broiler Poultry Litter." Sensors 24, no. 10 (May 11, 2024): 3049. http://dx.doi.org/10.3390/s24103049.
Abstract:
The traditional aviary decontamination process involves farmers applying pesticides to the aviary’s ground. These agricultural defenses are easily dispersed in the air, making the farmers susceptible to chronic diseases related to recurrent exposure. Industry 5.0 raises new pillars of research and innovation in transitioning to more sustainable, human-centric, and resilient companies. Based on these concepts, this paper presents a new aviary decontamination process that uses IoT and a robotic platform coupled with ozonizer (O3) and ultraviolet light (UVL). These clean technologies can successfully decontaminate poultry farms against pathogenic microorganisms, insects, and mites. Also, they can degrade toxic compounds used to control living organisms. This new decontamination process uses physicochemical information from the poultry litter through sensors installed in the environment, which allows accurate and safe disinfection. Different experimental tests were conducted to construct the system. First, tests related to measuring soil moisture, temperature, and pH were carried out, establishing the range of use and the confidence interval of the measurements. The robot’s navigation uses a back-and-forth motion that parallels the aviary’s longest side because it reduces the number of turns, reducing energy consumption. This task becomes more accessible because of the aviaries’ standardized geometry. Furthermore, the prototype was tested in a real aviary to confirm the innovation, safety, and effectiveness of the proposal. Tests have shown that the UV + ozone combination is sufficient to disinfect this environment.
38
Li, Xianglin, Yingjie Tan, Bo Yan, Yujian Zhao, and Hao Wang. "Demagnetization Modeling and Analysis for a Six-Phase Surface-Mounted Field-Modulated Permanent-Magnet Machine Based on Equivalent Magnetic Network." Energies 16, no. 16 (August 21, 2023): 6099. http://dx.doi.org/10.3390/en16166099.
Abstract:
Based on the magnetic gear effect, the field-modulated permanent-magnet machine (FMPMM) can realize the unequal pole design of the rotor PM field and the stator armature magnetic field. With the advantages of high torque density and high efficiency, the FMPMM has been widely studied in low-speed direct-drive applications. As a kind of machine excited by PMs, the performance of the FMPMM was affected by the demagnetization state. However, the method for establishing the FMPMM demagnetization model based on a finite element analysis (FEA) presented some problems, including tedious repeated modeling work and long calculation time-consuming under fine subdivision. Therefore, in this paper, a six-phase surface-mounted FMPMM was taken as an example, and an equivalent magnetic network (EMN) model was proposed for evaluating the machine performance under demagnetization. In order to realize the rapid establishing EMN models under diverse demagnetization types, the variable coercivity of PM was introduced. Furthermore, for the purpose of improving the calculation accuracy and shortening the calculation time, the least square method was used in fitting and analyzing the discrete results. Then, in order to verify the validity of the proposed EMN model, a prototype was fabricated and a testing platform was built. The air-gap flux density and the no-load back EMF obtained by the FEA, the proposed EMN model, and the experimental testing were compared. The results showed that the proposed EMN model can realize the rapid modeling and accurate analysis of the six-phase surface-mounted FMPMM under diverse demagnetization types.
39
Dehzangi, Arash, Farhad Larki, Sawal Hamid Md Ali, Sabar Derita Hutagalung, Md Shabiul Islam, Mohd Nizar Hamidon, Susthitha Menon, Azman Jalar, Jumiah Hassan, and Burhanuddin Yeop Majlis. "Study of the side gate junctionless transistor in accumulation region." Microelectronics International 33, no. 2 (May 3, 2016): 61–67. http://dx.doi.org/10.1108/mi-03-2015-0027.
Abstract:
Purpose The purpose of this paper is to analyse the operation of p-type side gate junctionless silicon transistor (SGJLT) in accumulation region through experimental measurements and 3-D TCAD simulation results. The variation of electric field components, carrier’s concentration and valence band edge energy towards the accumulation region is explored with the aim of finding the origin of SGJLT performance in the accumulation operational condition. Design/methodology/approach The device is fabricated by atomic force microscopy nanolithography on silicon-on-insulator wafer. The output and transfer characteristics of the device are obtained using 3-D Technology Computer Aided Design (TCAD) Sentaurus software and compared with experimental measurement results. The advantages of AFM nanolithography in contact mode and Silicon on Insulator (SOI) technology were implemented to fabricate a simple structure which exhibits the behaviour of field effect transistors. The device has 200-nm channel length, 100-nm gate gap and 4 μm for the distance between the source and drain contacts. The characteristics of the fabricated device were measured using an Agilent HP4156C semiconductor parameter analyzer (SPA). A 3-D TCAD Sentaurus tool is used as the simulation platform. The Boltzmann statistics is adopted because of the low doping concentration of the channel. Hydrodynamic model is taken to be as the main transport model for all simulations, and the quantum mechanical effects are ignored. A doping dependent Masetti mobility model was also included as well as an electric field dependent model with Shockley–Read–Hall (SRH) carrier recombination/generation. Findings We have obtained that the device is a normally on state device mainly because of the lack of work functional difference between the gate and the channel. Analysis of electric field components’ variation, carrier’s concentration and valence band edge energy reveals that increasing the negative gate voltage drives the device into accumulation region; however, it is unable to increase the drain current significantly. The positive slope of the hole quasi-Fermi level in the accumulation region presents mechanism of carriers’ movement from source to drain. The influence of electric field because of drain and gate voltage on charge distribution explains a low increasing of the drain current when the device operates in accumulation regime. Originality/value The proposed side gate junctionless transistors simplify the fabrication process, because of the lack of gate oxide and physical junctions, and implement the atomic force microscopy nanolithography for fabrication process. The optimized structure with lower gap between gate and channel and narrower channel would present the output characteristics near the ideal transistors for next generation of scaled-down devices in both accumulation and depletion region. The presented findings are verified through experimental measurements and simulation results.
40
Dahlmann, Adrian, Mathias Hoffmann, Gernot Verch, Marten Schmidt, Michael Sommer, Jürgen Augustin, and Maren Dubbert. "Benefits of a robotic chamber system for determining evapotranspiration in an erosion-affected, heterogeneous cropland." Hydrology and Earth System Sciences 27, no. 21 (November 1, 2023): 3851–73. http://dx.doi.org/10.5194/hess-27-3851-2023.
Abstract:
Abstract. In the light of the ongoing global climate crisis and the related increases in extreme hydrological events, it is crucial to assess ecosystem resilience and – in agricultural systems – to ensure sustainable management and food security. For this purpose, a comprehensive understanding of ecosystem water cycle budgets and spatiotemporal dynamics is indispensable. Evapotranspiration (ET) plays a pivotal role in returning up to 90 % of incoming precipitation back to the atmosphere. Here, we studied the impacts of soil types and management on an agroecosystem's seasonal cumulative ET (ETsum) and agronomic water use efficiency (WUEagro, the dry matter per unit of water used by the crop). To do so, a plot experiment with winter rye (17 September 2020 to 30 June 2021) was conducted in an eroded cropland which is located in the hilly and dry ground moraine landscape of the Uckermark region in northeastern Germany. Along the experimental plot (110 m × 16 m), two closed chambers were mounted on a robotic gantry crane system (FluxCrane as part of the AgroFlux platform) and used to determine ET. Three soil types representing the full soil erosion gradient related to the hummocky ground moraine landscape (extremely eroded: Calcaric Regosol; strongly eroded: Nudiargic Luvisol; non-eroded: Calcic Luvisol) and additional topsoil dilution (topsoil removal and subsoil admixture) were investigated (randomized block design, three replicates per treatment). Five different modeling approaches were used and compared in the light of their potential for reliable ETsum over the entire crop cultivation period and to reproduce short-term (e.g., diurnal) water flux dynamics. While machine-learning approaches such as support vector machines (SVMs) and artificial neural networks (with Bayesian regularization; ANN_BR) generally performed well during calibration, SVMs also provided a satisfactory prediction of measured ET during validation (k-fold cross-validation, k=5). We found significant differences in dry biomass (DM) and small trends in ETsum between soil types, resulting in different WUEagro. The extremely eroded Calcaric Regosol showed an up to 46 % lower ETsum and up to 54 % lower WUEagro compared to the non-eroded Calcic Luvisol. The key period contributing to 70 % of ETsum spanned the beginning of stem elongation in April to the harvest in June. However, differences in the ETsum between soil types and topsoil dilution resulted predominantly from small differences between the treatments throughout the cultivation rather than only during this short period of time.
41
Guo, Xinlei, Jiazhen Li, Kailin Yang, Hui Fu, Tao Wang, Yongxin Guo, Qingfu Xia, and Wei Huang. "Optimal design and performance analysis of hydraulic ram pump system." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 232, no. 7 (February 1, 2018): 841–55. http://dx.doi.org/10.1177/0957650918756761.
Abstract:
Hydraulic ram pump is an automatic water-pumping equipment generally used to pump drinking and irrigation water in mountainous and rural areas having short of power. In the past, it has been analyzed and optimized by fabricating various prototypes and conducting experiments and comparisons. This process is time and labor consuming and detailed flow features cannot be determined except efficiency, discharge, and period. In this paper, a method for the optimal design and performance analysis of hydraulic ram pump system with numerical simulation and physical experiment is presented to shorten the number of prototypes and develop high-performance product. The proposed evaluation indexes include head loss coefficient, drag coefficient, eccentric distance of pressure, and velocity distribution uniformity. Two types of structures, named front-enlargement and back-enlargement, were initially designed. According to the numerical simulation, the latter one has lower head loss coefficient and drag coefficient, larger eccentric distance of pressure and higher velocity distribution uniformity and was adopted in the novel hydraulic ram pump. Then, the design theory and method on adjustable and high-head experimental platform have been developed, so that the delivery head can be easily controlled and regulated in laboratory. Experiments were carried out for the delivery heads of 2.0 m and 2.7 m and comparisons were conducted with other products. The results show that, when the delivery head is less than 50 m, the efficiency of the new product ranges from 50% to 70% while the delivery flow is the largest. Its application in Liangshui River, Beijing, indicates that the novel hydraulic ram pump is a practical tool in fountain sight and for irrigation purpose without external power input.
42
Padilla-García, Erick Axel, Héctor Cervantes-Culebro, Alejandro Rodriguez-Angeles, and Carlos Alberto Cruz-Villar. "Selection/control concurrent optimization of BLDC motors for industrial robots." PLOS ONE 18, no. 8 (August 16, 2023): e0289717. http://dx.doi.org/10.1371/journal.pone.0289717.
Abstract:
This paper aims to concurrently select and control off-the-shelf BLDC motors of industrial robots by using a synergistic model-based approach. The BLDC motors are considered with trapezoidal back-emf, where the three-phase (a,b,c) dynamics of motors are modeled in a mechatronic powertrain model of the robot for the selection and control problem, defining it as a multi-objective dynamic optimization problem with static and dynamic constraints. Since the mechanical and electrical actuators’ parameters modify the robot’s performance, the selection process considers the actuators’ parameters, their control input, operational limits, and the mechanical output to the transmission of the robot joints. Then, three objective functions are to be minimized, the motor’s energy consumption, the tracking error, and the total weight of installed motors on the robot mechanism. The control parameterization approach via a cascade controller with PI controllers for actuators’ voltage and a PID controller for actuators’ torque is used to solve the multi-objective dynamic optimization problem. Based on simulations of the closed-loop system, a Pareto front is obtained to examine trade-offs among the objective functions before implementing any actuators in the existing robotic system. The proposed method is tested on an experimental platform to verify its effectiveness. The performance of an industrial robot with the actuators originally installed is compared with the results obtained by the synergic approach. The results of this comparison show that 10.85% of electrical power can be saved, and the trajectory tracking error improved up to 57.41% using the proposed methodology.
43
Massimo, Domenico Enrico, Vincenzo Del Giudice, Alessandro Malerba, Carlo Bernardo, Mariangela Musolino, and Pierfrancesco De Paola. "Valuation of Ecological Retrofitting Technology in Existing Buildings: A Real-World Case Study." Sustainability 13, no. 13 (June 22, 2021): 7001. http://dx.doi.org/10.3390/su13137001.
Abstract:
The world’s existing buildings are aged, in a state of deterioration and in need of interventions. When selecting the type of possible intervention to be applied, the choice falls between two alternatives: simple unsustainable ordinary maintenance versus ecological retrofitting i.e., an increase in the quality of the indoor environment and building energy saving using local bio-natural materials and products. The present research seeks to respond to the requests of recent comprehensive reviews which ask for the retrofitting of the world’s huge existing building stocks and portfolios by proposing an approach and testing it in a specific case study (at the unit, building and urban block level) which can then be carried out and repeated in the future on a larger urban scale. The real-world experimentation in the provided case study achieved the important outcome and goal of a Green Building strategy and post-carbon city framework i.e., the significant enhancement of the thermal performance of the buildings as a result of a few targeted key external works and the consequent saving of energy in those already existing (but not preserved and not included in the state national register or record of monuments) Liberty-style constructions. All the above show that these important existing buildings can be ecologically retrofitted at an affordable cost, although initially slightly more expensive than the cost of ordinary unsustainable maintenance. However, this difference is offset by the favorable pay-back period, which is fast, acceptable and of short duration. The tried and tested approach, the positive proposed case study and the experimental database-GIS joint platform (the details of which can be found in an additional supplementary research which is currently being carried out) are the bases on which a future decision support system will be proposed. This support system can be carried out as a tailor- made solution for the ecological retrofitting of the enormous existing building stocks and portfolios which must be considered on a larger scale i.e., at ward, quartier, city, regional and country level.
44
Bekker, Eric Botha, Daniel J. Holland, and Aaron Timothy Marshall. "Electrical Resistive Tomography to Analyse the Flow Behaviour in Redox Flow Batteries." ECS Meeting Abstracts MA2022-01, no. 48 (July 7, 2022): 2016. http://dx.doi.org/10.1149/ma2022-01482016mtgabs.
Abstract:
Redox flow batteries (RFBs) are re-emerging as a safe, scalable, efficient and versatile means of large-scale energy storage. Growing adoption of renewable energy generation has ushered a new optimism regarding future reduction in fossil fuel dependency; limiting further harm dealt to the climate and wider environment. However, this momentum demands more efficient energy storage solutions to reconcile power demand and the intermittent nature of wind, solar and tidal energy generation [1]. Without proper storage, reliable back-up generation – largely provided by fossil fuels – will continue to be an unavoidable reality [2]. RFBs utilise the electrochemical properties of dissolved metal ions to store and release energy. Independent sizing of electrolyte storage tanks and flexible power delivery contributes to the flexibility of RFBs compared to alternative battery technologies [3]. RFB reactions occur at the electrode-electrolyte interface, and thus the mass transport at this interface is a critical factor in determining the overall RFB performance. Most RFBs use porous electrodes, with a popular choice of material being carbon felt (CF) due to its low cost, chemical stability and high conductivity [4], although the hydrophobic nature of some CF can cause poor electrode ‘wettability’- decreasing the contact area between the electrode and the electrolyte. Further, electrolyte depletion and asymmetric flow can lead to the presence of ‘dead spots’ where the interface is inactive. Many studies have been conducted on CF to improve the electrochemical performance, using surface treatments, compression and channel flow to improve active area, wettability, and species transport [5-7]. These each have direct impact on current density, pressure drop, overpotentials, and energy efficiency. While the flow of electrolyte in the RFB porous electrodes can be modelled using computational fluid dynamics (CFD) [8], and experimentally assessed using x-ray tomography [9,10] and some optical visualisation methods [11], there are limited experimental methods which can be used on entire RFB stacks. In this study, we explore the use of electrical resistive tomography (ERT) to probe the flow of electrolyte through RFB electrodes. ERT has the advantage that it can provide a non-intrusive means of investigating the hydrodynamics of the otherwise opaque cell stack. Measurements were performed using an array of electrodes place around the perimeter of an RFB electrode chamber which contained conventional carbon felt electrodes. Sensitivity maps were generated using the COMSOL Multiphysics platform and compared with experimental measurements. The flow distribution was evaluated by using injections of concentrated KCl solutions into the background electrolyte. Overall, ERT demonstrated promise as a technique for characterising real-time flow dynamics in RFB stacks and for future research into porous electrode and flow field modifications. References [1] Ambec, S., and Crampes, C., Electricity Provision with Intermittent Sources of Energy. Resource and Energy Economics, Elsevier, 2012. 34: p.320-331. [2] Wagner, F., Electricity by intermittent sources: An analysis based on the German situation 2012. The European Physical Journal Plus, Springer, 2014. 129: 20. [3] Wang, W., et al., Recent Progress in Redox Flow Battery Research and Development. Advanced Functional Materials, Wiley, 2013. 23: p. 970-986. [4] Gonzalez-Garcia, J., et al., Characterization of a carbon felt electrode: structural and physical properties. Journal of materials Chemistry, 1999. 9: p. 419-426. [5] Wang, Q., et al., Experimental study on the performance of a vanadium redox flow battery with non-uniformly compressed carbon felt electrode. Applied Energy, Elsevier, 2018. 213: p. 293-305. [6] Wang, S., et al., Nitrogen-Doped Carbon Nanotube/Graphite Felts as Advanced Electrode Materials for Vanadium Redox Flow Batteries. The Journal of Physical Chemistry Letters, ACS Publications, 2012. 3: p. 2164-2167. [7] Kim, K., et al., The effects of surface modification on carbon felt electrodes for use in vanadium redox flow batteries. Materials Chemistry and Physics, 2011. 131: p. 547-553. [8] Oh, k., et al., Three-dimensional, transient, non-isothermal model of all-vanadium redox flow batteries. Energy, Elsevier, 2015. 81: p. 3-14. [9] Eifert, L., et al., Synchrotron X-ray Radiography and Tomography of Vanadium Redox Flow Batteries—Cell Design, Electrolyte Flow Geometry, and Gas Bubble Formation. ChemSusChem, Wiley, 2020. 13: 3154-3165. [10] Trogadas, P., et al., X-ray micro-tomography as a diagnostic tool for the electrode degradation in vanadium redox flow batteries. Electrochemistry Communications, Elsevier, 2014. 48: p. 155-159 [11] Bhattarai, A., et al., Study of flow behaviour in all-vanadium redox flow battery using spatially resolved voltage distribution. Journal of Power Sources, Elsevier, 2017. 360: p. 443- 452.
45
Shi, Xiaobo, Dingxuan Zhao, Yuhang Zhong, Jinming Chang, Tao Ni, and Xiangxian Chen. "Auxiliary Steering Control of Vehicle Driving with Force/Haptic Guidance." Sustainability 15, no. 16 (August 14, 2023): 12366. http://dx.doi.org/10.3390/su151612366.
Abstract:
The rapid development of the automobile industry has resulted in the development of many vehicles, increased traffic, and frequent accidents. The complexity of road conditions is a major contributor to the occurrence of traffic accidents. Drivers are distracted and hence unable to fully observe all road information and make optimal and timely driving decisions. This study proposes an auxiliary steering control system with force/tactile guidance (ASCFT) and its corresponding control strategy to address this problem. We combined vehicle autonomous path planning based on road condition information and the human–machine sharing control strategy, which integrated the manipulative force of the driver and a virtual guidance force on the steering wheel. Consequently, the ASCFT eliminated the mechanical connection between the steering wheel and the steering wheels in favor of a force/tactile-assisted steering structure, providing the driver with a sense of steering force based on road information. Additionally, we proposed a smooth vehicle trajectory optimization method based on the improved RRT algorithm and a path-following controller based on the forecast information to achieve auxiliary safety driving. The ASCFT’s performance was confirmed through constructing a fixed-base simulator experimental platform with the ASCFT. The results revealed that at the vehicle speed of 60 km/h and a handwheel rotation of 60°, the steering wheel was instantly released and turned back in about 3.5 s. Furthermore, predictive haptic feedback warned the driver of an upcoming obstacle.
46
Shang, Tianyi, and Weidong Ding. "Influence of gas pressure and gas type on pseudospark electron beam." Journal of Instrumentation 18, no. 09 (September 1, 2023): P09045. http://dx.doi.org/10.1088/1748-0221/18/09/p09045.
Abstract:
Abstract Pseudospark discharge is a discharge that occurs in the left band of the Paschen curve. According to previous studies, an electron beam will be generated in the initial stage of pseudospark discharge. This electron beam has the advantages of high energy, high current and self-confinement. It has a promising application in high-power microwave sources, surface treatment of metal materials, etc. To investigate the characteristics of this electron beam, a pseudospark discharge experimental platform is established in this paper. A pseudospark chamber is designed for pseudospark discharge. To trigger the discharge, a high voltage pulse trigger signal is generated by an avalanche transistor Marx circuit and a trigger unit is designed to generate trigger electrons. Faraday Cup is utilized to collect the electron beam and measure the electron waveform. In order to quantitatively characterize the electron beam, we define six electron beam characteristics, including trigger delay, peak current, electron beam charge, electron beam width, electron beam loop current ratio and electron beam loop charge ratio. To investigate the influence of gas pressure and gas type on electron beam characteristics, we experimentally obtained results of electron beam characteristics for different gas pressures and gas type. We mainly investigated the change rule of the electron beam characteristics when the gas pressure changes between 6 Pa and 20 Pa and the similarities and differences of the electron beams under the two gas environments, argon and nitrogen. We find that gas pressure can be used for the modulation of electron beam time delay. The width of the electron beam in the case of nitrogen has a very stable relationship with the gas pressure. Gas pressure and gas type are two important means of controlling the characteristics of pseudospark electron beams.
47
Raimondi, Lorenzo, Michele Manfredda, Nicola Mahne, Daniele Cocco, Flavio Capotondi, Emanuele Pedersoli, Maya Kiskinova, and Marco Zangrando. "Kirkpatrick–Baez active optics system at FERMI: system performance analysis." Journal of Synchrotron Radiation 26, no. 5 (August 12, 2019): 1462–72. http://dx.doi.org/10.1107/s1600577519007938.
Abstract:
FERMI is the first and only seeded EUV-SXR free-electron laser (FEL) facility available to users; it operates at Elettra – Sincrotrone Trieste (Italy) and it presents five operating endstations. Three of them, namely LDM (Low Density Matter), DiProI (Diffraction and Projection Imaging) and MagneDyn (Magneto-Dynamical studies), use a Kirkpatrick–Baez (KB) active X-ray optics system to focus the FEL pulses into the experimental chambers. The present work reports on the final results of the upgraded KB Active Optics Systems (KAOS), which have been mechanically modified in order to improve stability and repeatability with respect to the original design. The results have been obtained on both the FERMI FEL lines, FEL1 and FEL2, and are particularly relevant for the latter as it is the low-wavelength line recently opened to users. After a thorough description of the new mechanical layout of the system and the aspects that have been improved after the refurbishment, a set of simulations of the optical performances are presented. The code used to simulate the behavior of KAOS is WISEr, a physical-optics-based tool, which is freely accessible, and integrated into the Oasys platform, that takes into account the specific surface metrology characterization of the beamline mirrors, including figure errors and microroughness power spectral density. The results of WISEr are then used as a reference for the actual optimization of the optical system. This procedure relies heavily on a wavefront sensor (WFS) mounted out of focus to optimize the refocusing mirrors alignment as well as their curvature bending (by minimization of the coefficients of the Zernike wavefront expansion). Moreover, the WFS data are used to reconstruct the focal spot parameters by means of a back-propagation of the electric field. Finally, these results are compared with those obtained after the FEL ablation of a PMMA layer positioned on the focal plane, and analyzed ex situ in a post-mortem fashion. The mechanically refurbished optical system and the multi-technique alignment approach, aimed at optimizing the mirrors' curvature, pitch and roll angles, allowed a focal spot of 1.8 µm × 2.4 µm at 4.14 nm wavelength (FEL2) to be inferred, confirmed by the PMMA ablation imprints.
48
Shukla, Tanmay, and Ujjwal Kumar Kalla. "A BL-CC Converter-Based BLDC Motor Drive for Marine Electric Vehicle Applications." International Transactions on Electrical Energy Systems 2022 (June 1, 2022): 1–18. http://dx.doi.org/10.1155/2022/7026462.
Abstract:
This article presents a BLDC (permanent magnet brushless DC) motor drive for marine electric vehicle (MEV) application. The presented scheme uses bridgeless canonical cell (BL-CC) converter with center-tapped inductor (shown as two separate inductors for analysis purpose) for source-side power factor correction (PFC); however, the BL-CC converter requires two inductors. In the presented scheme use of one center-tapped inductor eliminates the requirement of one extra inductor. Thus, center-tapped inductor usage in BLDC motor drive results in decrement in components count. The BL-CC converter-based BLDC motor drive scheme do not require extra back-feeding diodes like other bridgeless (BL) schemes, but it uses inbuilt antiparallel diodes of insulated gate bipolar transistor (IGBT) switches for the same purpose this again leads to decrement in required component count. In this work, PFC BL-CC converter is operated in discontinuous inductor current (DIC) mode to attain better power quality. The DIC mode operation requires only one voltage sensor to sense DC-link voltage, whereas in continuous conduction mode (CCM), the sensor requirement increases to three (two voltage sensors and one current sensor). The PFC BL-CC converter also eliminates the diode bridge rectifier stage. The elimination of one extra inductor, two extra back-feeding diodes, DBR stage and also requirement of only one voltage sensor in DIC mode operation instead of three sensors for CCM implies reduction in components count which implies the reduction in cost and also the volume and weight of the BLDC motor drive. The weight reduction for marine (on-board) electric vehicle is very important as this enhances the vehicle performance. This paper also presents the detailed mathematical modeling and stability analysis of presented BL-CC converter using pole zero map and Bode plot. The BL-CC converter-based BLDC motor driving system for MEV application for DIC mode operation has been developed in the laboratory as well as on MATLAB/Simulink platform and simulated MATLAB and real-time experimental results have been presented to validate the presented BLDC motor drive under steady-state and dynamic operating conditions.
49
Kumar, Surender, and R. S. Bharj. "Experimental Analysis of Solar Assisted Refrigerating Electric Vehicle." International Journal of Recent Technology and Engineering 9, no. 5 (January 30, 2021): 305–15. http://dx.doi.org/10.35940/ijrte.e5278.019521.
Abstract:
Most refrigerating systems are driven by an internal combustion engine that increased the conventional vehicle's oil consumption and tailpipe emissions. The solar-assisted refrigerating electric vehicle (SAREV) system powered by a hybrid energy mode has been designed. The hybrid energy (solar + grid) was stored in the battery bank to complete this vehicle's necessary functions. The PV panels are prominently incorporated into this vehicle rooftop to charge the battery bank. In this study, the integrated system was driven by a hybrid energy mode that reducing the wastage and deterioration during temporary storage and transportation in different areas. The performance of the integrated system was tested under different operating conditions. The effect of load variation on maximum speed and travelling distance of vehicle was analyzed. The battery bank charging and discharge performance were studied with and without solar energy. The refrigerator was consuming 116 Wh energy per day to maintain a -12 oC lower temperature on the no-load condition at the higher thermostat position. The refrigerator was run continuously for 4-6 days on battery bank energy and 7-10 days on the full load condition of hybrid energy. The vehicle was travelling at a maximum of 23 km/h speed on full load condition. The vehicle needed torque 14-16 N-m at the initial phase for each load condition. Torque demand was decreasing with the increasing speed of the vehicle. The full-charged battery bank's initial voltage was 51.04 V, and the cut-off voltage was 46.51 V. The vehicle was covering a distance of 62.4 km with the battery bank alone at full load condition. It was travelling 68.3 km distance with hybrid energy mode. The vehicle's integrated system was the best in maintaining battery performance, power contribution capability, and drive range enhancement.
50
Yolhamid, Mohd Najib Abdul Ghani, Mohd Norsyarizad Razali, M. N. Azzeri, Mohd Shukri Mohd Yusop, Ahmad Mujahid Ahmad Zaidi, and Noh Zainal Abidin. "Development and Experimental Investigation of a Marine Vessel Utilizing the Energy Ship Concept for Far Offshore Wind Energy Conversion." Transactions on Maritime Science 10, no. 2 (October 21, 2021): 305–17. http://dx.doi.org/10.7225/toms.v10.n02.001.
Abstract:
The energy ship is a concept for offshore wind energy capture which has received very little attention until today. To this date, there had not been yet an experimental proof of concept. In order to tackle this issue, an experimental platform and data acquisition system has been developed. A 5.5m long sailing catamaran served as a platform equipped with a 240mm diameter water turbine. The energy ship platform has been tested several times in the actual river to investigate the workability of the platform and data acquisition system. Results show that energy ship platform can produced 500W electric power for a true wind speed of 10 knots.