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1
Yun, Eun Jeong, Jong Tae Park, and Chong Gun Yu. "An maximum power point tracking interface circuit for low-voltage DC-type energy harvesting sources." Bulletin of Electrical Engineering and Informatics 11, no. 6 (December 1, 2022): 3108–18. http://dx.doi.org/10.11591/eei.v11i6.4124.
Анотація:
This paper presents a maximum power point tracking (MPPT) interface circuit for low-voltage DC-type energy harvesting sources such as light and thermal energy. Most energy harvesting systems used in miniature-sized sensor systems require start-up circuits because the output voltages of small-sized energy transducers are very low and not enough to directly power electronic systems. The proposed interface circuit is driven directly by the low output voltages of small size energy transducers, eliminating the need for complex start-up circuitry. A simple MPPT controller with the fractional open-circuit voltage (FOCV) method is designed and fabricated in a 65-nm complementary metal oxide semiconductor (CMOS) process. Measurement results show that the designed circuit can track the MPP voltage even in the presence of the open-circuit voltage fluctuations and can operate properly at operating voltages as low as 0.3 V. The interface circuit achieves a peak power efficiency of 97.1% and an MPPT accuracy of over 98.3%.
2
Baimel, Dmitry, Saad Tapuchi, Yoash Levron, and Juri Belikov. "Improved Fractional Open Circuit Voltage MPPT Methods for PV Systems." Electronics 8, no. 3 (March 14, 2019): 321. http://dx.doi.org/10.3390/electronics8030321.
Анотація:
This paper proposes two new Maximum Power Point Tracking (MPPT) methods which improve the conventional Fractional Open Circuit Voltage (FOCV) method. The main novelty is a switched semi-pilot cell that is used for measuring the open-circuit voltage. In the first method this voltage is measured on the semi-pilot cell located at the edge of PV panel. During the measurement the semi-pilot cell is disconnected from the panel by a pair of transistors, and bypassed by a diode. In the second Semi-Pilot Panel method the open circuit voltage is measured on a pilot panel in a large PV system. The proposed methods are validated using simulations and experiments. It is shown that both methods can accurately estimate the maximum power point voltage, and hence improve the system efficiency.
3
Penella, Maria Teresa, and Manel Gasulla. "A Simple and Efficient MPPT Method for Low-Power PV Cells." International Journal of Photoenergy 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/153428.
Анотація:
Small-size PV cells have been used to power sensor nodes. These devices present limited computing resources and so low complexity methods have been used in order to extract the maximum power from the PV cells. Among them, the fractional open circuit voltage (FOCV) method has been widely proposed, where the maximum power point of the PV cell is estimated from a fraction of its open circuit voltage. Here, we show a generalization of the FOCV method that keeps its inherent simplicity and improves the tracking efficiency. First, a single-diode model for PV cells was used to compute the tracking efficiency versus irradiance. Computations were carried out for different values of the parameters involved in the PV cell model. The proposed approach clearly outperformed the FOCV method, specially at low irradiance, which is significant for powering sensor nodes. Experimental tests performed with a 500 mW PV panel agreed with these results.
4
Olzhabay, Yerassyl, Annie Ng, and Ikechi A. Ukaegbu. "Perovskite PV Energy Harvesting System for Uninterrupted IoT Device Applications." Energies 14, no. 23 (November 27, 2021): 7946. http://dx.doi.org/10.3390/en14237946.
Анотація:
The performance of perovskite solar cells (PSCs) has been improved throughout the years. These photovoltaic (PV) cells can be used to power Internet of Things (IoT) devices for indoor applications. A perovskite PV energy harvesting system with a stand-by battery that continuously powers an IoT device is developed in this work. The battery is required to complement the PSCs when the latter have difficulties in power delivery during low or no irradiance. The performance of the energy harvesting circuit as well as the battery charge and discharge scenarios are investigated. Voltage matching between the PSC and the battery is achieved by a boost converter. The PSC energy harvesting system uses fractional open-circuit voltage (FOCV) based maximum power point tracking (MPPT), which utilizes a Sample and Hold (S&H) circuit. The FOCV technique is based on a comparison of the perovskite PV open circuit voltages and the maximum power points. For each irradiance level, the maximum power point is unique, and this work uses a light-dependent resistor (LDR) to adjust the scaling constant in MPPT. Case studies include various scenarios under 1000 lux fluorescent light and 1 sun irradiance as well as a consideration of different battery states.
5
Bu, Ling, Shengjiang Quan, Jiarong Han, Feng Li, Qingzhao Li, and Xiaohong Wang. "On-Site Traversal Fractional Open Circuit Voltage with Uninterrupted Output Power for Maximal Power Point Tracking of Photovoltaic Systems." Electronics 9, no. 11 (October 29, 2020): 1802. http://dx.doi.org/10.3390/electronics9111802.
Анотація:
The fractional open-circuit voltage (FOCV) method is commonly adopted to track maximal power point of photovoltaic systems due to easy implementation and cost-effectiveness. However, the FOCV method is confronted with unstable output power and limited tracking accuracy. This paper proposes a novel on-site traversal FOCV method with uninterrupted output power and increased tracking accuracy through simulation and experimental verifications. Each solar cell is connected with a bypass diode and switching circuitry, so that specific solar cell can be traced and measured consecutively for determining its maximal power point (MPP). MATLAB/Simulink simulation results show that, in the time-varying irradiance case, the proposed method achieves a low ripple factor of 0.13% in 11–13 h and 0.88% in 9–15 h, under the typical 24 h irradiance curve. In the spatial-varying irradiance case, the accuracy of the proposed method reaches 99.85%. Compared with other FOCV methods, like pilot cell and semi pilot cell methods, the proposed method is of higher accuracy with a limited ripple effect. Experimental results show that this method can effectively trace different output performance of specific solar cell while generating stable output voltage with a low ripple factor of 1.55%, proving its compatibility with distributed sensing and applicability in smart photovoltaic systems.
6
Han, Lei, Xia Wang, and Guang Wei Wang. "Maximum Power Point Tracking for the Micro-Scale Photovoltaic Power System." Applied Mechanics and Materials 734 (February 2015): 771–74. http://dx.doi.org/10.4028/www.scientific.net/amm.734.771.
Анотація:
In this paper, we give a comprehensive consideration on the maximum power point tracking (MPPT) algorithm for micro-scale solar energy harvesting system. Basing on the comparison analysis the MPPT algorithm of fractional open circuit voltage (FOCV) is certificated to be the simplest method among all the algorithms focus on small size photovoltaic devices. As a validation, an example is given to demonstrate the effectiveness of the proposed idea.
7
Carandell, Matias, Daniel Mihai Toma, Andrew S. Holmes, Joaquín del Río, and Manel Gasulla. "Experimental Validation of a Fast-Tracking FOCV-MPPT Circuit for a Wave Energy Converter Embedded into an Oceanic Drifter." Journal of Marine Science and Engineering 11, no. 4 (April 11, 2023): 816. http://dx.doi.org/10.3390/jmse11040816.
Анотація:
Wave Energy Converters (WECs) are an ideal solution for expanding the autonomy of surface sensor platforms such as oceanic drifters. To extract the maximum amount of energy from these fast-varying sources, a fast maximum power point tracking (MPPT) technique is required. Previous studies have examined power management units (PMU) with fast MPPT circuits, but none of them have demonstrated their feasibility in a real-world scenario. In this study, the performance of a fast-tracking fractional open circuit voltage (FOCV)-MPPT circuit (sampling period TMPPT of 48 ms) is compared with a commercial slow-tracking PMU (TMPPT of 16 s) in a monitored sea area while using a small-scale, pendulum-type WEC. A specific low-power relaxation oscillator circuit is designed to control the fast MPPT circuit. The results demonstrate that by speeding up the sampling frequency of the MPPT circuit, the harvested energy can be increased by a factor of three.
8
Im, Yun Chan, Seung Soo Kwak, Jonghyun Park, and Yong Sin Kim. "Intermittent FOCV Using an I-V Curve Tracer for Minimizing Energy Loss." Applied Sciences 11, no. 19 (September 27, 2021): 9006. http://dx.doi.org/10.3390/app11199006.
Анотація:
Conventional fractional open-circuit voltage (FOCV) methods in maximum power point tracking (MPPT) are widely adopted for their simple structure and low computing power requirements. However, under mismatch and environmental changing conditions, the FOCV methods introduce a large amount of energy loss due to their maximum power point being fixed at the initial setup. To reduce energy loss, the intermittent FOCV MPPT proposed in this paper regularly refreshes all the parameters for each condition in time by using an I-V curve tracer. The proposed intermittent FOCV consists of two phases: the scan and set phases. In scan phase, the I-V curve of a photovoltaic (PV) cell is scanned and its power is calculated. In set phase, the global MPP of the PV cell is extracted and set by controlling the 8-bit capacitance array. Simulation and calculation based on experimental results with a single PV cell show that the energy loss of the proposed intermittent FOCV under daily temperature and illuminance distributions decreased by up to 99.9% compared to that of the conventional FOCV.
9
Marroquín-Arreola, Ricardo, Jinmi Lezama, Héctor Ricardo Hernández-De León, Julio César Martínez-Romo, José Antonio Hoyo-Montaño, Jorge Luis Camas-Anzueto, Elías Neftalí Escobar-Gómez, Jorge Evaristo Conde-Díaz, Mario Ponce-Silva, and Ildeberto Santos-Ruiz. "Design of an MPPT Technique for the Indirect Measurement of the Open-Circuit Voltage Applied to Thermoelectric Generators." Energies 15, no. 10 (May 23, 2022): 3833. http://dx.doi.org/10.3390/en15103833.
Анотація:
This paper presents the design of a maximum power point-tracking (MPPT) technique for DC–DC converters that are used in energy-harvesting systems based on thermoelectric generators. This technique is based on the analysis of the characteristics of the converter to measure the open-circuit voltage indirectly. The main contribution of this article is that the algorithm measures the voltage at the maximum power point without the need to disconnect the source of the circuit, as happens when the fractional open-circuit voltage (FOCV) technique is used. The algorithm is based on a predetermined initial duty cycle, which is applied to the circuit, and the input voltage and input current are read. With these values, the open-circuit voltage and short-circuit current are calculated with equations obtained from the circuit. Then, it calculates the duty cycle at the maximum power point and applies it to the circuit. If this duty cycle does not obtain the maximum power from the circuit, the algorithm starts a second stage based on fuzzy logic to calculate an increase or decrease in the duty cycle. The designed technique was evaluated using a topology based on a DC–DC flyback converter variant and was compared with the P&O technique and obtained better results. The designed technique provides between 3.9% and 5.6% more power to the load than the P&O technique in a 20 W system.
10
Kim, Hyeon-Joong, and Chong-Gun Yu. "Piezoelectric energy harvesting interface with fast open-circuit voltage sampling." Journal of Asian Scientific Research 14, no. 2 (April 29, 2024): 237–50. http://dx.doi.org/10.55493/5003.v14i2.5062.
Анотація:
This paper presents a piezoelectric energy harvesting interface with fast open-circuit voltage (VOC) sampling and a wide operating frequency range. The fractional open-circuit voltage (FOCV) method is the primary method for maximum power point tracking (MPPT) in energy harvesting systems, due to its easy implementation and relatively low cost. For this method to be efficient, it is necessary to shorten the time required for VOC sampling. To minimize power loss due to VOC sampling, a novel technique is proposed that is capable of sampling the VOC within a time shorter than half a cycle by using an adaptive tracking pulse instead of conventional fixed ones. We also present a peak detector design technique that can operate across a broad frequency spectrum and adapt to diverse vibration scenarios. The proposed technique reduces the duty cycle of the tracking pulse to 0.42%, which is 3.7 times smaller than the conventional 1.56%. The proposed circuit, designed using a 0.35μm complementary metal oxide semiconductor (CMOS) process, consumes just 94nA at 100Hz, 3V VOC, and a 1kΩ load. In a 2~4V VOC range and a 15~500Hz frequency range, the MPPT efficiency exceeds 95%, peaking at 99.9%, and the power efficiency remains over 93%, reaching a maximum of 97.7%.
11
Nzoundja Fapi, C. B., P. Wira, and M. Kamta. "Real-Time Experimental Assessment of a New MPPT Algorithm Based on the Direct Detection of the Short-Circuit Current for a PV System." Renewable Energy and Power Quality Journal 19 (September 2021): 598–603. http://dx.doi.org/10.24084/repqj19.358.
Анотація:
To substantially increase the efficiency of photovoltaic (PV) systems, it is important that the Maximum Power Point Tracking (MPPT) system has an output close to 100%.This process is handled by MPPT algorithms such as Fractional Open-Circuit Voltage (FOCV), Perturb and Observe (P&O), Fractional Short-Circuit Current (FSCC), Incremental Conductance (INC), Fuzzy Logic Controller (FLC) and Neural Network (NN) controllers. The FSCC algorithm is simple to be implemented and uses only one current sensor. This method is based on the unique existence of the linear approximation between the Maximum Power Point (MPP) current and the short-circuit current in standard conditions. The speed of this MPPT optimization technic is fast, however this algorithm needs to short-circuit the PV panel each time in order to obtain the short circuit current. This process leads to energy losses and high oscillations. In order to improve the FSCC algorithm, we propose a method based on the direct detection of the shortcircuit current by simply reading the output current of the PV panel. This value allows directly calculating the short circuit current by incrementing or decrementing the solar irradiation. Experimental results show time response attenuation, little oscillations, power losses reduction and better MPPT accuracy of the enhanced algorithm compared to the conventional FSCC method.
12
Zakki, M. I. M., M. N. M. Hussain, I. R. Ibrahim, N. A. Ismail, and M. N. Ibrahim. "Distributed Fast Maximum Power Point Tracking Technique for Mismatched Module Application." Indonesian Journal of Electrical Engineering and Computer Science 6, no. 2 (May 1, 2017): 225. http://dx.doi.org/10.11591/ijeecs.v6.i2.pp225-232.
Анотація:
<p>This paper propose distributed fast maximum power point tracking (DFMPPT) technique to achieve maximum power point tracking (MPPT). This paper implements the algorithm in distributed MPPT (DMPPT) architecture for mismatched condition with single module, and string connection. The MPPT method uses indirect and direct MPPT method by fractional open-circuit voltage (FOCV) with incremental conductance (INC) for high-speed maximum energy harvesting. This method is proven to be fast for tracking maximum power point (MPP) which achieves the peak power less in 1.7ms via for a single module with efficiency of 99.7% compared to the recent MPPT technique to reach MPP in 1.75ms with 95.8% efficiency. While for string configuration, the efficiency of the whole system is rated by 85.583% by taking 8.675ms to reach global MPP.</p>
13
Zouari, Manel, Slim Naifar, Ghada Bouattour, Nabil Derbel, and Olfa Kanoun. "Energy management based on fractional open circuit and P-SSHI techniques for piezoelectric energy harvesting." tm - Technisches Messen 86, no. 1 (January 28, 2019): 14–24. http://dx.doi.org/10.1515/teme-2017-0121.
Анотація:
AbstractSelf-powered energy management circuits make energy harvesting converters more efficient and more reliable. This paper presents an improvement of a Maximum Power Point Tracking (MPPT) technique applied on a Parallel Synchronized Switch Harvesting on Inductor (P-SSHI) technique for piezoelectric vibration converters. The aims are to detect the unstable vibrational state, optimize the output voltage and maximize the output power of the piezoelectric transducer.First, the P-SSHI technique is implemented without an MPPT technique. Then, an MPPT technique based on Fractional Open Circuit (FOC) voltage method is implemented. An improvement of the FOC method is proposed to enhance the capability of the Piezoelectric Energy Harvesting (PEH) system. The comparison between different simulation results shows that by using the same input parameters, the maximum efficiency for the PEH system based on the P-SSHI technique implemented without MPPT is 8.82 % whereas the maximum efficiency of the system based on the (FOC) voltage MPPT method is 13.77 %. A significant improvement of the PEH system is obtained by using the modified (FOC) method, where the efficiency reached 24.59 %.
14
Hmidet, Ali, Umashankar Subramaniam, Rajvikram Madurai Elavarasan, Kannadasan Raju, Matias Diaz, Narottam Das, Kashif Mehmood, Alagar Karthick, M. Muhibbullah, and Olfa Boubaker. "Design of Efficient Off-Grid Solar Photovoltaic Water Pumping System Based on Improved Fractional Open Circuit Voltage MPPT Technique." International Journal of Photoenergy 2021 (October 14, 2021): 1–18. http://dx.doi.org/10.1155/2021/4925433.
Анотація:
The main application of off-grid solar photovoltaic (SPV) systems is water extraction in rural areas where access to the grid is restricted. In this application, photovoltaic (PV) and pump system regulation are crucial to increase its overall efficiency. In this context, this work presents a simple and efficient off-grid SPV water pumping system (SPVWPS). The designed system is based on a DC-DC boost converter, a three-phase DC-AC inverter, and a three-phase induction motor (IM) coupled to the centrifugal pump. The proposed solution is operated using a control strategy that associates an improved fractional open-circuit voltage (FOCV) method for maximum power point tracking (MPPT) and closed-loop scalar control. This association avoids the use of a speed sensor/encoder and a current sensor for the IM. Finally, the effectiveness of the proposed off-grid SPVWPS and its control system for both steady-state and dynamic conditions of insolation change is verified using a 1KVA rated prototype. The relevance of the drive is also checked in various operating conditions and is found to be adequate for pumping water. Moreover, the proposed method guarantees a fast response, less oscillations around the MPP, a system efficiency of 99%, and a high flow rate due to the extraction of maximum power.
15
Harrison, Ambe, Eustace Mbaka Nfah, Jean de Dieu Nguimfack Ndongmo, and Njimboh Henry Alombah. "An Enhanced P&O MPPT Algorithm for PV Systems with Fast Dynamic and Steady-State Response under Real Irradiance and Temperature Conditions." International Journal of Photoenergy 2022 (November 8, 2022): 1–21. http://dx.doi.org/10.1155/2022/6009632.
Анотація:
This paper presents an enhanced perturb and observe (P&O) method for reconciling the trade-off problem between the dynamic response and steady-state oscillations in maximum power point tracking (MPPT). The constraint of having to sacrifice either the dynamic response or the steady-state oscillations has been solved. The method uses the relationship between the open-circuit voltage and maximum power voltage from the fractional open-circuit voltage (FOCV) MPPT method to establish a valid, reduced, and confined search space within which an enhanced P&O via dynamic adaptive step size terminates the search for the maximum power point. The feasibility of the proposed method has been validated by comparing its performance with the conventional P&O algorithm. It was noted that the proposed method increased the operational efficiency of the PV module to 99.89%, reduced the tracking time to 1.8 ms, and preserved the good steady-state response with a power attenuation of less than 0.10 W or relative 0.16% under MATLAB environment. An experimental setup was used to collect real irradiance and temperature data which was used in real-time simulations. The enhanced P&O method was able to resist abrupt changes in irradiance and temperature as it effectively and efficiently followed the maximum power point (MPP). Finally, to appreciate the supremacy of the proposed method, it was compared to nineteen different MPPT methods from literature. The comparison showed that the enhanced P&O MPPT method is highly efficient and effective for MPPT in photovoltaic (PV) generation systems.
16
Shadlu, Milad Samady. "Comparison of Maximum Power Point Tracking (MPPT) Algorithms to Control DC-DC Converters in Photovoltaic Systems." Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) 12, no. 4 (August 23, 2019): 355–67. http://dx.doi.org/10.2174/2352096511666180530075244.
Анотація:
Background: Using the solar energy by photovoltaic arrays is constantly increasing and has been considered as one of the cleanest sources of energy in recent years. One of the ways to reduce the cost of photovoltaic systems is to maximize the power delivered to the load. On the other hand, changing the load leads to change the operating point of the solar conversion system and causes deviation from the maximum power point (MPP). Methods: For this reason, in various research studies, attention has been paid to MPPT methods applicable in photovoltaic systems. In this paper, a comparison is performed between conventional MPPT methods including Perturb and Observe (P&O), Incremental Conductance (INC), Fractional Open Circuit Voltage (FOCV), Ripple Correlation Control (RCC) and Extremum Seeking Control (ESC). Only current and voltage parameters of the PV panel are measured instantly and used to generate control signals. However, the output voltage of the PV cells is relatively low without using the DC-DC converters. Results: Therefore, high-performance DC-DC converters need to convert the low voltage PV arrays into high DC voltages to handle the 220 VAC systems. Conclusion: Accordingly, in this study, conventional DC-DC converters including Boost, Buck and Buck-Boost converters are investigated, and each of them is simulated using different MPPT controllers and the results are compared together. It is worth noting that all of the simulations are carried out using MATLAB/Simulink.
17
Shebani, Muamer M., and Tariq Iqbal. "Dynamic Modeling, Control, and Analysis of a Solar Water Pumping System for Libya." Journal of Renewable Energy 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/8504283.
Анотація:
In recent years, one of the suitable solar photovoltaic (PV) applications is a water pumping system. The simplest solar PV pumping system consists of PV array, DC-DC converter, DC motor, and water pump. In this paper, water pumping system sizing for Libya is evaluated based on a daily demand using HOMER software, and dynamic modeling of a solar PV water pumping system using a Permanent Magnet DC (PMDC) motor is presented in Matlab/Simulink environment. The system performance with maximum power point tracking (MPPT) based on Fractional Open Circuit Voltage (FOCV) is evaluated with and without a battery storage system. In some applications, a rated voltage is needed to connect a PMDC motor to a PV array through a DC-DC converter and in other applications the input voltage can vary. The evaluation of the system is based on the performance during a change in solar irradiation. Using Matlab/Simulink, simulation results are assessed to see the efficiency of the system when it is operating at a specific speed or at the MPPT. The results show that an improvement in the system efficiency can be achieved when the PMDC motor is running at a specific speed rather than at the peak PV power point.
18
Basha, CH Hussaian, and C. Rani. "Different Conventional and Soft Computing MPPT Techniques for Solar PV Systems with High Step-Up Boost Converters: A Comprehensive Analysis." Energies 13, no. 2 (January 12, 2020): 371. http://dx.doi.org/10.3390/en13020371.
Анотація:
Solar photovoltaic (PV) systems are attracting a huge focus in the current energy scenario. Various maximum power point tracking (MPPT) methods are used in solar PV systems in order to achieve maximum power. In this article, a clear analysis of conventional MPPT techniques such as variable step size perturb and observe (VSS-P&O), modified incremental conductance (MIC), fractional open circuit voltage (FOCV) has been carried out. In addition, the soft computing MPPT techniques such as fixed step size radial basis functional algorithm (FSS-RBFA), variable step size radial basis functional algorithm (VSS-RBFA), adaptive fuzzy logic controller (AFLC), particle swarm optimization (PSO), and cuckoo search (CS) MPPT techniques are presented along with their comparative analysis. The comparative analysis is done under static and dynamic irradiation conditions by considering algorithm complexity, tracking speed, oscillations at MPP, and sensing parameters. The single-diode model PV panel and double-diode model PV panel are also compared in terms of fill factor (FF) and maximum power extraction. Clear insight is presented supporting the suitability of MPPT techniques for different types of converter configurations.
19
Thanh Pham, Hong, and Le Van Dai. "A Feasible MPPT Algorithm for the DC/DC Boost Converter." International journal of electrical and computer engineering systems 14, no. 6 (July 12, 2023): 713–24. http://dx.doi.org/10.32985/ijeces.14.6.11.
Анотація:
One of the most promising forms of renewable energy is solar energy. However, efficient exploitation of this energy form is a topic of great interest, especially in obtaining the maximum amount of power from the solar photovoltaic (PV) system under changing environmental conditions. To solve this problem, it is necessary to propose an optimal algorithm. Therefore, this paper presents a feasible maximum power point tracking (MPPT) technique for DC/DC boost converters applied in load-connected stand-alone PV systems to extract the maximum available power. This proposed method is based on the combination of the modified perturb and observe (P&O) and fractional open circuit voltage (FOCV) algorithms. The effectiveness of the proposed technique is verified via time-domain simulation of the load-connected stand-alone PV system using PSIM software. The simulation results show a tracking efficiency with an average value of 99.85%, 99.87%, and 99.96% for tracking the MPP under varying loads, irradiation, and simultaneously varying temperature, load, and irradiation, respectively. In addition, tracking time is always stable at 0.02 sec for changing weather conditions in the large range. Therefore, the results of the proposed method indicate advantages compared to the conventional method.
20
Anil N. Patel. "Comparative Analysis of Mppt Techniques for Grid Tie Solar Pv Applications." Journal of Electrical Systems 20, no. 7s (May 28, 2024): 2453–63. http://dx.doi.org/10.52783/jes.4053.
Анотація:
For effective energy harvesting, photovoltaic (PV) systems must produce their maximum amount of power. This is especially true for grid-tie applications, where the objective is to feed generated power into the grid. The different Maximum Power Point Tracking (MPPT) methods used in grid-tie solar PV systems are compared in this paper. In order to guarantee that PV arrays function at their maximum power point in a variety of environmental circumstances, MPPT algorithms are essential. A DC-DC boost converter is also used for interfacing the load and photovoltaic module. Result is simulated in MATLAB/Simulink environment, and all the condition is kept same for both techniques in simulation for the best outcomes of this comparative study. The efficiency, accuracy, convergence speed, and implementation complexity of several MPPT techniques—Perturb and Observe (P&O), Incremental Conductance (INC), Fractional Open Circuit Voltage (FOCV), and Particle Swarm Optimization (PSO)—are assessed and contrasted in this study. The performance of each technique under various operating conditions is demonstrated through MATLAB/Simulink simulation results, which help in the selection of the optimal MPPT method for grid-tie solar PV applications.
21
Srinivas, Paruchuri, and P. Swapna. "Maximum Power Point Tracking Algorithm for Advanced Photovoltaic Systems." International Journal on Recent and Innovation Trends in Computing and Communication 10, no. 9 (September 30, 2022): 26–39. http://dx.doi.org/10.17762/ijritcc.v10i9.5748.
Анотація:
Photovoltaic (PV) systems are the major nonconventional sources for power generation for present power strategy. The power of PV system has rapid increase because of its unpolluted, less noise and limited maintenance. But whole PV system has two main disadvantages drawbacks, that is, the power generation of it is quite low and the output power is nonlinear, which is influenced by climatic conditions, namely environmental temperature and the solar irradiation. The natural limiting factor is that PV potential in respect of temperature and irradiation has nonlinear output behavior. An automated power tracking method, for example, maximum power point tracking (MPPT), is necessarily applied to improve the power generation of PV systems. The MPPT methods undergo serious challenges when the PV system is under partial shade condition because PV shows several peaks in power. Hence, the exploration method might easily be misguided and might trapped to the local maxima. Therefore, a reasonable exploratory method must be constructed, which has to determine the global maxima for PV of shaded partially. The traditional approaches namely constant voltage tracking (CVT), perturb and observe (P&O), hill climbing (HC), Incremental Conductance (INC), and fractional open circuit voltage (FOCV) methods, indeed some of their improved types, are quite incompetent in tracking the global MPP (GMPP). Traditional techniques and soft computing-based bio-inspired and nature-inspired algorithms applied to MPPT were reviewed to explore the possibility for research while optimizing the PV system with global maximum output power under partially shading conditions. This paper is aimed to review, compare, and analyze almost all the techniques that implemented so far. Further this paper provides adequate details about algorithms that focuses to derive improved MPPT under non-uniform irradiation. Each algorithm got merits and demerits of its own with respect to the converging speed, computing time, complexity of coding, hardware suitability, stability and so on.
22
Pathy, Subramani, Sridhar, Thamizh Thentral, and Padmanaban. "Nature-Inspired MPPT Algorithms for Partially Shaded PV Systems: A Comparative Study." Energies 12, no. 8 (April 16, 2019): 1451. http://dx.doi.org/10.3390/en12081451.
Анотація:
PV generating sources are one of the most promising power generation systems in today’s power scenario. The inherent potential barrier that PV possesses with respect to irradiation and temperature is its nonlinear power output characteristics. An intelligent power tracking scheme, e.g., maximum power point tracking (MPPT), is mandatorily employed to increase the power delivery of a PV system. The MPPT schemes experiences severe setbacks when the PV is even shaded partially as PV exhibits multiple power peaks. Therefore, the search mechanism gets deceived and gets stuck with the local maxima. Hence, a rational search mechanism should be developed, which will find the global maxima for a partially shaded PV. The conventional techniques like fractional open circuit voltage (FOCV), hill climbing (HC) method, perturb and observe (P&O), etc., even in their modified versions, are not competent enough to track the global MPP (GMPP). Nature-inspired and bio-inspired MPPT techniques have been proposed by the researchers to optimize the power output of a PV system during partially shaded conditions (PSCs). This paper reviews, compares, and analyzes them. This article renders firsthand information to those in the field of research, who seek interest in the performance enhancement of PV system during inhomogeneous irradiation. Each algorithm has its own advantages and disadvantages in terms of convergence speed, coding complexity, hardware compatibility, stability, etc. Overall, the authors have presented the logic of each global search MPPT algorithms and its comparisons, and also have reviewed the performance enhancement of these techniques when these algorithms are hybridized.
23
Chang, Chengcheng, Yanping Zheng, and Yang Yu. "Estimation for Battery State of Charge Based on Temperature Effect and Fractional Extended Kalman Filter." Energies 13, no. 22 (November 14, 2020): 5947. http://dx.doi.org/10.3390/en13225947.
Анотація:
The electric vehicle has become an important development direction of the automobile industry, and the lithium-ion power battery is the main energy source of electric vehicles. The accuracy of state of charge (SOC) estimation directly affects the performance of the vehicle. In this paper, the first order fractional equivalent circuit model of a lithium iron phosphate battery was established. Battery capacity tests with different charging and discharging rates and open circuit voltage tests were carried out under different ambient temperatures. The conversion coefficient of charging and discharging capacity and the simplified open circuit voltage model considering the hysteresis characteristics of the battery were proposed. The parameters of the first order fractional equivalent circuit model were identified by using a particle swarm optimization algorithm with dynamic inertia weight. Finally, the recursive formula of a fractional extended Kalman filter was derived, and the battery SOC was estimated under continuous Dynamic Stress Test (DST) conditions. The results show that the estimation method has high accuracy and strong robustness.
24
Hsu, Tsung-Wei, Hung-Hsien Wu, Dian-Lin Tsai, and Chia-Ling Wei. "Photovoltaic Energy Harvester With Fractional Open-Circuit Voltage Based Maximum Power Point Tracking Circuit." IEEE Transactions on Circuits and Systems II: Express Briefs 66, no. 2 (February 2019): 257–61. http://dx.doi.org/10.1109/tcsii.2018.2838672.
25
Molinié, Philippe. "Analytical and numerical modelling of the electrostatic behaviour of highly insulating materials in the time domain." Journal of Physics: Conference Series 2702, no. 1 (February 1, 2024): 012017. http://dx.doi.org/10.1088/1742-6596/2702/1/012017.
Анотація:
Abstract The usual response of an insulator subjected to a voltage step involves time power laws. We present here mathematical tools allowing to calculate this time domain response in open circuit after an initial charge deposit, within the framework of linear systems theory, using linear fractional transfer functions. In the time domain, the inverse Laplace transform of the data taken from the frequency domain leads to Mittag-Leffler functions, generalizing the Debye exponential response to an extended fractional α-order response. The open-circuit boundary conditions are different from the closed-circuit ones. We nevertheless demonstrate that using a transfer function deduced from the Cole-Cole response in closed-circuit, a precise analytical formula of the potential decay after an initial charge deposit may be established, and a numerical computation of this decay may be performed using easily available software. Applying the superposition principle, the voltage return following a brief short circuit may also be deduced. Experimental results are presented and the limits of the superposition principle applied to real materials are discussed.
26
Nadeem, Ahsan, Hadeed Ahmed Sher, and Ali Faisal Murtaza. "Online fractional open‐circuit voltage maximum output power algorithm for photovoltaic modules." IET Renewable Power Generation 14, no. 2 (January 8, 2020): 188–98. http://dx.doi.org/10.1049/iet-rpg.2019.0171.
27
Alzahrani, Ahmad. "A Fast and Accurate Maximum Power Point Tracking Approach Based on Neural Network Assisted Fractional Open-Circuit Voltage." Electronics 9, no. 12 (December 21, 2020): 2206. http://dx.doi.org/10.3390/electronics9122206.
Анотація:
This paper presents an enhanced maximum power point tracking approach to extract power from photovoltaic panels. The proposed method uses an artificial neural network technique to improve the fractional open-circuit voltage method by learning the correlation between the open-circuit voltage, temperature, and irradiance. The proposed method considers temperature variation and can eliminate the steady-state oscillation that comes with conventional algorithms, which improves the overall efficiency of the photovoltaic system. A comparison with the traditional and most widely used algorithms is discussed and shows the difference in performance. The presented algorithm is implemented with a Ćuk converter and tested under various weather and irradiance conditions. The results validate the competitiveness of the algorithm against other algorithms.
28
Puneet, Singh Ajal, and Dahiya Ratna. "A Novel Computational Approach towards Maximum Power Point Tracking for Solar Photovoltaic and Wind Energy Systems." Applied Mechanics and Materials 592-594 (July 2014): 2331–35. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.2331.
Анотація:
In this paper a new approach for maximum power point tracking (MPPT) is proposed. The fractional open circuit voltage based MPPT states that the photovoltaic (PV) array voltage corresponding to the maximum power gives a linear dependence with respect to array open circuit voltage for different irradiation and temperature levels. This method is the easiest and simplest of all the MPPT methods but the disconnection of the PV array from the load on regular intervals for the sampling of the array voltage causes significant power loss. A new and simple approach is proposed by the simple linear equation of line for calculating the duty cycle of the boost converter which will extract the maximum power for the particular radiations. This topology can also be used for Wind energy systems but here the simulation is done with solar photovoltaic only. The proposed work is verified using MATLAB/SIMULNK and simulation results shows a clear improvement in achieving the desired results.
29
Hassan, Aakash, Octavian Bass, and Mohammad A. S. Masoum. "An improved genetic algorithm based fractional open circuit voltage MPPT for solar PV systems." Energy Reports 9 (December 2023): 1535–48. http://dx.doi.org/10.1016/j.egyr.2022.12.088.
30
Zhang, Qi, Naxin Cui, Yan Li, Bin Duan, and Chenghui Zhang. "Fractional calculus based modeling of open circuit voltage of lithium-ion batteries for electric vehicles." Journal of Energy Storage 27 (February 2020): 100945. http://dx.doi.org/10.1016/j.est.2019.100945.
31
N. Luta, Doudou, and Atanda K. Raji. "Comparing Fuzzy rule-based and fractional Open Circuit Voltage MPPT techniques in a fuel cell stack." International Journal of Engineering & Technology 8, no. 4 (October 19, 2019): 402. http://dx.doi.org/10.14419/ijet.v8i4.29343.
Анотація:
The concept of power tracking was at first applied to renewable power systems and especially those based on solar and wind to extract as much power as possible from them. Both types of power systems operate on the principle of converting either solar or wind into electricity. Thus, their output power is direct dependent on the solar radiation for solar power systems and on the wind speed for wind generators. To maintain efficient system operations, the output power of these power systems is optimized through maximum power tracking techniques. In the similar vein, fuel cell stacks display nonlinear output powers resulting from internal limitations and operating parameters such as tem-perature, hydrogen and oxygen partial pressures and humidity levels, etc., leading to a reduced system performance. It is critical to extract as much power as possible from the stack, thus, to prevent also an excessive fuel use. To ensure that, the power converter interfaced to the stack must be able to self-adjust its parameters continuously, hence modifying its voltage and current depending upon the maximum power point position. Diverse techniques are utilized to extract maximum power from the fuel-cell stack. In this paper, a fractional open circuit voltage and fuzzy rule based maximum power tracking techniques are considered and compared. The proposed system consists of a 50 kW Proton Exchange Membrane fuel cell interfaced to a DC-to-DC boost converter. The converter is designed to deliver 1.2 kV from 625 V input voltage. The simulation is carried out under Matlab/Simulink environment.
32
Różowicz, Sebastian, Andrzej Zawadzki, Maciej Włodarczyk, and Antoni Różowicz. "Modeling of Internal Combustion Engine Ignition Systems with a Circuit Containing Fractional-Order Elements." Energies 15, no. 1 (January 4, 2022): 337. http://dx.doi.org/10.3390/en15010337.
Анотація:
This paper discusses the research and analysis of the dynamics of high-voltage generating systems. The test subject is an ignition system modelled by a set of two induction coils with an open ferromagnetic core that constitutes an ignition coil. The essence of the tests involved the application of magnetic coupling of the fractional order that enabled taking into account the non-idealities of the coils and the connector that implements the ignition point. The paper contains the results of a theoretical analysis, supported by digital simulations. The conducted experiments confirm the purposefulness of the conducted analyses and the possibility of modeling real objects based on circuits with fractional-order elements.
33
Bárcenas-Bárcenas, Ernesto, Diego R. Espinoza-Trejo, José A. Pecina-Sánchez, Héctor A. Álvarez-Macías, Isaac Compeán-Martínez, and Ángel A. Vértiz-Hernández. "An improved Fractional MPPT Method by Using a Small Circle Approximation of the P–V Characteristic Curve." Mathematics 11, no. 3 (January 18, 2023): 526. http://dx.doi.org/10.3390/math11030526.
Анотація:
This paper presents an analytical solution to the maximum power point tracking (MPPT) problem for photovoltaic (PV) applications in the form of an improved fractional method. The proposal makes use of a mathematical function that describes the relationship between power and voltage in a PV module in a neighborhood including the maximum power point (MPP). The function is generated by using only three points of the P–V curve. Next, by using geometrical relationships, an analytical value for the MPP can be obtained. The advantage of the proposed technique is that it provides an explicit mathematical expression for calculation of the voltage at the maximum power point (vMPP) with high accuracy. Even more, complex calculations, manufacturer data, the measurements of short circuit current (iSC) and open-circuit voltage (vOC) are not required, making the proposal less invasive than other solutions. The proposed method is validated using the P–V curve of one PV module. Experimental work demonstrates the speed in the calculation of vMPP and the feasibility of the proposed solution. In addition, this MPPT proposal requires only the typical and available measurements, namely, PV voltage and current. Consequently, the proposed method could be implemented in most PV applications.
34
Cevik, Ismail, and Suat U. Ay. "A Low-Power and Low-Voltage Power Management Strategy for On-Chip Micro Solar Cells." Journal of Sensors 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/739871.
Анотація:
Fundamental characteristics of on-chip micro solar cell (MSC) structures were investigated in this study. Several MSC structures using different layers in three different CMOS processes were designed and fabricated. Effects of PN junction structure and process technology on solar cell performance were measured. Parameters for low-power and low-voltage implementation of power management strategy and boost converter based circuits utilizing fractional voltage maximum power point tracking (FVMPPT) algorithm were determined. The FVMPPT algorithm works based on the fraction between the maximum power point operation voltage and the open circuit voltage of the solar cell structure. This ratio is typically between 0.72 and 0.78 for commercially available poly crystalline silicon solar cells that produce several watts of power under typical daylight illumination. Measurements showed that the fractional voltage ratio is much higher and fairly constant between 0.82 and 0.85 for on-chip mono crystalline silicon micro solar cell structures that produce micro watts of power. Mono crystalline silicon solar cell structures were observed to result in better power fill factor (PFF) that is higher than 74% indicating a higher energy harvesting efficiency.
35
Hwu, K. I., W. C. Tu, and C. R. Wang. "Photovoltaic Energy Conversion System Constructed by High Step-Up Converter with Hybrid Maximum Power Point Tracking." International Journal of Photoenergy 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/275210.
Анотація:
A photovoltaic energy conversion system, constructed by high step-up converter with hybrid maximum power point tracking (HMPPT), is presented. A voltage converter with a high voltage conversion ratio is proposed, which is simple in circuit and easy in control. After this, such a converter operating with a suitable initial duty cycle of the pulsewidth-modulated (PWM) control signal, together with the proposed HMPPT algorithm combining the fractional open-circuit voltage method and the incremental conductance method, is applied to the photovoltaic energy conversion system. By doing so, not only the maximum power point tracking speed can be increased, but also the oscillation around the maximum power point can be reduced. Aside from these, the field programmable gate array (FPGA) is used as a control kernal of the overall system, so as to realize the HMPPT and fully digitalized control. Finally, via a PV simulator, some experimental results are provided to verify the effectiveness of the proposed photovoltaic energy conversion system.
36
Ebrahim, M. A., H. A. AbdelHadi, H. M. Mahmoud, E. M. Saied, and M. M. Salama. "Optimal Design of MPPT Controllers for Grid Connected Photovoltaic Array System." International Journal of Emerging Electric Power Systems 17, no. 5 (October 1, 2016): 511–17. http://dx.doi.org/10.1515/ijeeps-2016-0077.
Анотація:
Abstract Integrating photovoltaic (PV) plants into electric power system exhibits challenges to power system dynamic performance. These challenges stem primarily from the natural characteristics of PV plants, which differ in some respects from the conventional plants. The most significant challenge is how to extract and regulate the maximum power from the sun. This paper presents the optimal design for the most commonly used Maximum Power Point Tracking (MPPT) techniques based on Proportional Integral tuned by Particle Swarm Optimization (PI-PSO). These suggested techniques are, (1) the incremental conductance, (2) perturb and observe, (3) fractional short circuit current and (4) fractional open circuit voltage techniques. This research work provides a comprehensive comparative study with the energy availability ratio from photovoltaic panels. The simulation results proved that the proposed controllers have an impressive tracking response. The system dynamic performance improved greatly using the proposed controllers.
37
Abdul-Razzaq, Islam K., Mohamed M. Fahim Sakr, and Yasir G. Rashid. "Comparison of PV panels MPPT techniques applied to solar water pumping system." International Journal of Power Electronics and Drive Systems (IJPEDS) 12, no. 3 (September 1, 2021): 1813. http://dx.doi.org/10.11591/ijpeds.v12.i3.pp1813-1822.
Анотація:
<span lang="EN-US">This paper deals with an advanced design for a pump powered by solar energyto supply agricultural lands with water and also the maximum power point is used to extract the maximum value of the energy available inside the solar panels and comparing between techniques MPPT such as Incremental conductance, perturb & observe, fractional short current circuit, and fractional open voltage circuit to find the best technique among these. The solar system is designed with main parts: photovoltaic (PV) panel, direct current/direct current (DC/DC) converter, inverter, filter, and in addition, the battery is used to save energy in the event that there is an increased demand for energy and not to provide solar radiation, as well as saving energy in the case of generation more than demand. This work was done using the matrix laboratory (MATLAB) simulink program.</span>
38
Zhou, Minghao, Kemeng Wei, Xiaogang Wu, Ling Weng, Hongyu Su, Dong Wang, Yuanke Zhang, and Jialin Li. "Fractional-Order Sliding-Mode Observers for the Estimation of State-of-Charge and State-of-Health of Lithium Batteries." Batteries 9, no. 4 (April 1, 2023): 213. http://dx.doi.org/10.3390/batteries9040213.
Анотація:
Lithium batteries are widely used in power storage and new energy vehicles due to their high energy density and long cycle life. The accurate and real-time estimation for the state-of-charge (SoC) and the state-of-health (SoH) of lithium batteries is of great significance to improve battery life, reliability, and utilization efficiency. In this paper, three cascaded fractional-order sliding-mode observers (FOSMOs) are designed for the estimation of SoC by observing the terminal voltage, the polarization voltage, and the open-circuit voltage of a lithium cell, respectively. Furthermore, to calculate the value of the SoH, two FOSMOs are developed to estimate the capacity and internal resistance of the lithium cell. The control signals of the observers are continuous by utilizing fractional-order sliding manifolds without low-pass filters. Compared with the existing sliding-mode observers for SoC and SoH, weaker chattering, faster response, and higher estimation accuracy are obtained in the proposed method. Finally, the experiment tests demonstrate the validity and feasibility of the proposed observer design method.
39
Maldon, B., and N. Thamwattana. "A Fractional Diffusion Model for Dye-Sensitized Solar Cells." Molecules 25, no. 13 (June 28, 2020): 2966. http://dx.doi.org/10.3390/molecules25132966.
Анотація:
Dye-sensitized solar cells have continued to receive much attention since their introduction by O’Regan and Grätzel in 1991. Modelling charge transfer during the sensitization process is one of several active research areas for the development of dye-sensitized solar cells in order to control and improve their performance and efficiency. Mathematical models for transport of electron density inside nanoporous semiconductors based on diffusion equations have been shown to give good agreement with results observed experimentally. However, the process of charge transfer in dye-sensitized solar cells is complicated and many issues are in need of further investigation, such as the effect of the porous structure of the semiconductor and the recombination of electrons at the interfaces between the semiconductor and electrolyte couple. This paper proposes a new model for electron transport inside the conduction band of a dye-sensitized solar cell comprising of TiO 2 as its nanoporous semiconductor. This model is based on fractional diffusion equations, taking into consideration the random walk network of TiO 2 . Finally, the paper presents numerical solutions of the fractional diffusion model to demonstrate the effect of the fractal geometry of TiO 2 on the fundamental performance parameters of dye-sensitized solar cells, such as the short-circuit current density, open-circuit voltage and efficiency.
40
Arulmurugan, R., N. Sivakumar, and E. Baraneetharan. "Analysis of interleaved fuzzy Logic MPPT approach for PV system." Journal of Physics: Conference Series 2570, no. 1 (August 1, 2023): 012002. http://dx.doi.org/10.1088/1742-6596/2570/1/012002.
Анотація:
Abstract In this article, a detailed novel interleaved fuzzy logic control based Maximum Power Point Algorithm was designed. It was derived from the conventional hill climbing method, which is used to track solar Photo Voltaic (PV) systems over changing temperature and irradiance. The proposed system composed of the PV panel source, Maximum Power Point Tracking (MPPT) with designed interleaved Fuzzy Logic controller, DC to DC charge controller, and load. The designed fuzzy logic controller contains the two fuzzy subsets, one fuzzy concentrate the change in power with respect to change in voltage and another fuzzy concentrate the change in power with respect to change in current, compare with two fuzzy model uses to track the path more perfect compare to existing method as a novelty of the article. The proposed interleaved fuzzy MPPT optimally tune the parameters of the controller. The proposed system analyzed the few sub criteria, such as time response, stability and power efficiency. The performance of the presented controller has been validated with conventional controllers such as fractional open circuit approach, fractional short circuit approach and hill climbing approach. The proposed leads the highest tracking performance compared to existing. In addition, the proposed performed effectively in different environmental conditions.
41
Ojha, Nirdesh, Claas Müller та Holger Reinecke. "Parametric Analysis of μ-Electric Discharge Machining of Non-Conductive Si3N4". Applied Mechanics and Materials 564 (червень 2014): 560–65. http://dx.doi.org/10.4028/www.scientific.net/amm.564.560.
Анотація:
Electric discharge machining (EDM) is an electro-thermal non-traditional machining process used to machine conductive materials. EDM process can be used to machine non-conductive ceramics by applying an assisting electrode (AE) on top of the insulating ceramics. The initial discharges occur between the tool electrode and the assisting electrode. During the spark erosion process an intrinsic conductive layer is continuously produced on the insulating ceramic. This transitional conductive layer ensures that the electric contact is sustained. However, result of parametric analysis of the EDM of non-conductive ceramics is not available. This paper presents a parametric study to evaluate the influence of five major EDM process parameters (peak current, open-circuit voltage, servo, pulse width and gap voltage) on two response variables (material removal rate and the tool ware rate) when structuring non-conductive Si3N4ceramics using the die-sinking μ-EDM process with the help of the AE. A set of experimental trials planned with fractional factorial design with a resolution of V was performed to evaluate the primary, two-factor and quadratic effects.
42
KARABAŞ, Abdullah, Onur Ozdal MENGI, and Kenan YANMAZ. "Metaheuristic Algorithm Based Battery Charge Control Design in Solar Energy Systems." Karadeniz Fen Bilimleri Dergisi 13, no. 4 (December 18, 2023): 1251–83. http://dx.doi.org/10.31466/kfbd.1179554.
Анотація:
Yenilenebilir güneş enerji sistemlerinde, kısıtlı zaman diliminde ve değişen atmosferik şartlarda güneş enerjisinden elde edilecek enerjinin verimli şekilde yüke aktarılması son derece önemli ve gereklidir. Güneş enerjisinden maksimum seviyede yararlanamayan sistemlerde, Fotovoltaik (PV) panel sayısı artışı, verim düşüşü ve maliyet artışından bahsedilebilir. Bu durumda; güneş enerjisinden alıcıların maksimum seviyede yararlanabilmesi, PV panellerden en üst seviyede yararlanabilmeye bağlıdır. Bunun içinde Maksimum Güç Noktası İzleyiciler (Maximum Power Point Tracker - MPPT) kullanılmalıdır. Bu çalışmada MPPT tekniklerinden Değiştir - Gözle (Perturb & Observe - P&O) yöntemi, Artan İletkenlik Yöntemi (Incremental Conductance - IC) ve Kısmi Açık-Devre Gerilim Yöntemi (Fractional Open-Circuit Voltage) kullanılmıştır. Yük üzerinde sabit bir gerilim elde edebilmek amacıyla kurşun asit bataryanın şarj ve deşarjını kontrol etmek için parametreleri Parçacık Sürüsü Optimizasyon (Particle Swarm Optimization - PSO) algoritması ve Çakal Optimizasyon Algoritması (Coyote Optimization Algorithm - COA) gibi metasezgisel algoritmalarla hesaplanmış kontrolör önerilmiştir.
43
Huang, Yu-Pei, and Sheng-Yu Hsu. "A performance evaluation model of a high concentration photovoltaic module with a fractional open circuit voltage-based maximum power point tracking algorithm." Computers & Electrical Engineering 51 (April 2016): 331–42. http://dx.doi.org/10.1016/j.compeleceng.2016.01.009.
44
Yu-Pei Huang. "A Rapid Maximum Power Measurement System for High-Concentration Photovoltaic Modules Using the Fractional Open-Circuit Voltage Technique and Controllable Electronic Load." IEEE Journal of Photovoltaics 4, no. 6 (November 2014): 1610–17. http://dx.doi.org/10.1109/jphotov.2014.2351613.
45
Ahmad, K. A., A. Abd Manaf, Z. Hussain Hussain, and Z. Janin. "Design Flexural Piezoelectric Acoustic Transducers Array based d33 Mode Polarization." Indonesian Journal of Electrical Engineering and Computer Science 10, no. 1 (April 1, 2018): 59. http://dx.doi.org/10.11591/ijeecs.v10.i1.pp59-65.
Анотація:
Piezoelectric Acoustic Transducer (PAT) is a transducers used in many application such as medical diagnostic, medical ultrasonic imaging and underwater acoustic applications. Latest research, PAT were investigated in marine application and underwater acoustic imaging. Conventional PAT is design based on sensing element, Piezoelectric Material, matching layer and backing layer. But the conventional method still has problem with issues of narrow bandwidth, directivity and low sensitivity. This problem is occurred when the transducer need to increase the image resolution. The size of single element will become smaller to meet the requirement of high resolution. PZT-5H have high piezoelectric constant (d31) and low dielectric loss. It is chosen as sensing element in this design of PAT because it will increase the sensitivity of transducers. The PAT is design based on d33 mode polarization to improve the receiving sensitivity. The fabrication process are included wet etching on Printed Circuit Board (PCB), spin coated Polydimethylsiloxane (PDMS), and baked transducer on hot plate. PAT is characterized using Pulse-Echo method. Pulse-Echo method will determine the sensitivity, directivity and operating bandwidth of acoustic transducers in underwater applications. Open circuit receiving voltage (OCRV) is voltage response to determine the sensitivity of acoustic transducer. The commercial projector and hydrophone will calibrate to obtain the reliability of result. In cross talk test, at some particular frequency, Pin 2 and Pin 3 have low sensitivity value. It is because Pin 2 and Pin 3 received low acoustic wave pressure. The PAT array based d33 mode polarization shows it has more receiving sensitive compared to commercial acoustic transducers. The design transducer has sensitivity at -56 dB re 1V/µPa at resonance frequency, 100kHz and fractional bandwidth at 30%.
46
Leoni and Pantoli. "SPICE Model Identification Technique of a Cheap Thermoelectric Cell Applied to DC/DC Design with MPPT Algorithm for Low-Cost, Low-Power Energy Harvesting." Applied Sciences 9, no. 18 (September 7, 2019): 3744. http://dx.doi.org/10.3390/app9183744.
Анотація:
In this work, an identification technique of a simple, measurements-based SPICE (Simulation Program with Integrated Circuit Emphasis) model is presented for small low-cost Peltier cells used in thermoelectric generator (TEG) mode for low-temperature differences. The collection of electric energy from thermal sources is an alternative solution of great interests to the problem of energy supply for low-power portable devices. However, materials with thermoelectric characteristics specifically designed for this purpose are generally expensive and therefore often not usable for low cost and low power applications. For these reasons, in this paper, we studied the possibility of exploiting small Peltier cells in TEG mode and a method to maximize the efficiency of these objects in energy conversion and storage since they are economical, easy to use, and available with different characteristics on the market. The identification of an accurate model is a key aspect for the design of the DC/DC converter, in order to guarantee maximum efficiency. For this purpose, the SPICE model has been validated and used in a design example of a DC/DC converter with maximum power point tracking (MPPT) algorithm with fractional open-circuit voltage. The results showed that it is possible to obtain a maximum power of 309 µW with a Peltier cell 2 × 2 cm at a ΔT of 16 °C and the designed SPICE DC/DC converter performance proved the improvement and optimization value given by the TEG model identification.
47
Gottesfeld, Shimshon. "(Invited, Digital Presentation) The Low T Water Electrolyzer Current-Voltage Relationship: Electrocatalysis and More." ECS Meeting Abstracts MA2023-01, no. 36 (August 28, 2023): 1971. http://dx.doi.org/10.1149/ma2023-01361971mtgabs.
Анотація:
As described in a recent publication [1], mechanisms of electrocatalytic processes have a common pattern which provides the basis for a universal rate expression for electrode processes in fuel cells. The same universal rate expression is applicable for low T water electrolyzers, serving as an effective predictor of the form of the non-linear dependence of the overpotential h on log J. The general form of this equation is exemplified by equation (1): (1) J (E) = Cr g Fk0A* x f(E - E0 surf. redox) 10^(- D H#/2.3RT) 10^ (E- E0 cell)/b. It can be seen that this expression considers two effects of the electrode potential on the current: one is the effect on the activation energy through the term 10^(E- E0 cell)/b, and the other is the effect of the electrode potential on the fractional population of active surface sites (or the fractional surface coverage by adsorbed intermediates), described in Eq 1 as: f(E - E0 surf.redox) where E0 surf.redox is the standard potential of a surface redox couple which “mediates” the faradaic electrode process . Consequently, E0 surf.redox determines the value of the onset potentialfor that faradaic process. Overpotential-driven activation of catalyst surface sites is a key component of processes taking place in electrodes of water electrolyzers, much the same as in the case of the fuel cell. The reason is that, as a rule, catalyst surface sites are inactive under open circuit conditions. In the case of the anode of the water electrolyzer , the origin of the main component of the electrode kinetic losses, the reason is the relatively low oxidation state of the metal ions in the oxyhydroxide catalyst surface sites. Iron sites are typically Fe(III) and iridium sites are Ir(IV) under open circuit conditions in contact with the aqueous electrolyte and O2 , whereas a higher oxidation state is required to withdraw electrons from water to form an *OH adsorbed intermediate. Such higher oxidation states are first generated at an anode overpotential of the order 0.15-0.20V, i.e., at ~1.40V vs. RHE. Highly active OER catalyst are all characterized by an oxide redox couple M+nox/ M+(n+1)ox of E0 ~1.40V , as can be verified from relevant Pourbaix diagrams. This means that the loss associated with catalyst site activation is significantly lower than in the case of the ORR, where it is near 0.30V. It is interesting to examine the reasons for this apparent advantage of the oxide catalyst in the OER vs. the PGM catalyst in the ORR. As explained in detail in reference [1], each electrocatalytic process is characterized by a two-step sequence: a pre-RDS step (“pre-step”) which involves surface site activation, followed by the rate determining step. The pre-step determines the onset potential and the RDS determines the rate of the electrocatalytic process at a given potential beyond the onset [1]. To large degree, the electrocatalysts of highest activity are determined by the value of the onset potential, as is best set to achieve the optimized bond strength required by the “Sabatier Principle” for the catalytic processes, which all involve bond formation followed by bond scission. In the case of the ORR process, Pt and it’s alloys which exhibit highest activity are characterized by a M/Mox surface potential of ~085V vs. RHE This means that forming a surface population of 1% of active M sites for the ORR, requires a minimum overpotential of ~0.30V whereas metal catalysts of lower oxygen affinity than Pt , which exhibit “bare” metal sites at much lower overpotentials, fail to reactively bond the diatomic oxygen molecule in the RDS. In the case of the OER, the relatively high activity of oxide catalyst sites in forming *OH ,as reflected by the low onset overpotential, does not seem to result in an excessive scission energy for the *OOH intermediate which most likely forms last in the sequence of the OER. Finally and importantly, the typical form of the polarization curves observed for low T aqueous electrolyzers, is fully accounted for by Eq. 1 which predicts very well the form of the non-linear h vs. log J polarization characteristics. Reference: [1] Shimshon Gottesfeld , A Perspective of Polymer Electrolyte Fuel cell Science and Technology, highlighting a general mechanistic pattern and a general rate expression for electrocatalytic processes , JES, in press
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Jiang, Hong, Bo Li, Qi Zhang, Xuewei Li, and Jiaming Fan. "Study and implementation of a novel high‐efficiency piezoelectric energy harvesting circuit." International Journal of Circuit Theory and Applications, November 13, 2023. http://dx.doi.org/10.1002/cta.3852.
Анотація:
SummaryThis paper proposes a self‐powered SSHI piezoelectric energy extraction circuit combined with Modified FOCV‐MPPT technology, which analyzes the electrical characteristics of S‐SSHI operation. The paper demonstrates that the determination of the optimal operating state of S‐SSHI can be determined independently of the open‐circuit voltage. Based on the key parameters obtained from the theoretical analysis, the FOCV‐MPPT strategy is modified, and the corresponding functional circuit is designed. This strategy serves as an intermediate stage between S‐SSHI and the load, addressing the dependence of S‐SSHI output power on the load while avoiding the power supply interruption issue of the traditional FOCV‐MPPT strategy. In addition, the higher output power provided by S‐SSHI improves the utilization of MPPT technology. The correctness of the investigations is verified through the simulation and experiments. By using self‐powered S‐SSHI, the proposed circuit increases the output power of PEH by a factor of 2.46. In the open‐circuit voltage range of 2–7 V, the average maximum power tracking efficiency achieved 90.1%. The maximum tracking efficiency can reach 98%.
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Zeng, Jiawei, Shunli Wang, Wen Cao, Mengyun Zhang, Carlos Fernandez, and Josep M. Guerrero. "Improved fractional‐order hysteresis‐equivalent circuit modeling for the online adaptive high‐precision state of charge prediction of urban‐electric‐bus lithium‐ion batteries." International Journal of Circuit Theory and Applications, August 12, 2023. http://dx.doi.org/10.1002/cta.3767.
Анотація:
SummaryAccurate state of charge (SOC) estimation is based on a precise battery model and is the focus of the battery management system (BMS). First, based on the second‐order RC equivalent circuit model and Grunwald–Letnikov (G‐L) definition, the high‐precision fractional‐order hysteresis‐equivalent circuit model (FH‐ECM) is established considering the open‐circuit voltage hysteresis effect. Then, the global parameters of the battery model are identified using a particle swarm algorithm optimized by the genetic algorithm (GA‐PSO). Third, a fractional‐order adaptive unscented Kalman filter (FOAUKF) algorithm is derived to estimate the SOC of lithium‐ion batteries. Finally, the feasibility of the model and algorithm is verified under complex working conditions. Under the dynamic stress test (DST) condition, the accuracy of model terminal voltage has been improved by 37.83%, and the error of SOC estimation has been reduced by 11.28%. Under Beijing bus dynamic stress test (BBDST) condition, the model terminal voltage accuracy has been improved by 51.44%, and the SOC estimation error has been reduced by 35.71%. The experimental results fully confirm the accuracy of the fractional‐order hysteresis‐equivalent circuit modeling method.
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Yue, Wei, Cong-zhi Liu, Liang Li, Xiang Chen, and Fahad Muhammad. "A nonlinear fractional-order H∞ observer for SOC estimation of battery pack of electric vehicles." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, February 18, 2021, 095440702199434. http://dx.doi.org/10.1177/0954407021994349.
Анотація:
This work is focused on designing a fractional-order [Formula: see text] observer and applying it into the state of charge (SOC) estimation for lithium-ion battery pack system. Firstly, a fractional order equivalent circuit model based on the fractional capacitor is established and identified. Secondly, the SOC estimation method based on the fractional-order [Formula: see text] observer is proposed. The nonlinear intrinsic relationship between the open-circuit voltage and SOC is described as a polynomial function, and its Lipschitz proposition has been discussed. Then, the nonlinear observer design criterion is established based on the Lyapunov method. Finally, the effectiveness of the proposed method is verified with high accuracy and robustness by the experiment results.