Статті в журналах: "Simulation accuracy in power engineering"

1

Zheng, Hui Ping, Min Xue, Yan Zhao, Xin Yuan Liu, and Yu Han. "A Comprehensive Evaluation Method on Dynamic Simulation Accuracy of Power System." Applied Mechanics and Materials 541-542 (March 2014): 869–74. http://dx.doi.org/10.4028/www.scientific.net/amm.541-542.869.

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In order to overcome the shortcomings of the present accuracy assessment methods of power system dynamic simulation, this paper focuses the permanent single phase short-circuit fault which occurs in a large probability in power grids,and selects the typical electrical quantities which is very concerned in engineering after the fault happened. A time-scale based error criteria on simulation validation is proposed, and a comprehensive error criteria according to the average errors between simulation data and actual data is proposed to evaluate objectively the simulation accuracy of the typical electrical quantities. Considering the variation characteristics of the electrical quantities, the simulation accuracy evaluation of a single electrical element is expended to the simulation accuracy evaluation of the entire network, so not only the comprehensive evaluation about the model and its parameters but also the information for model modification and parameter correction can be obtained. The effectiveness of the proposed method is verified by the numerical results on the New England 10 Unit 39 Bus powers system.

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2

Bu, Jing, and Ning Qiang Jiang. "Analysis of Power System’s Critical Damping." Advanced Materials Research 219-220 (March 2011): 586–90. http://dx.doi.org/10.4028/www.scientific.net/amr.219-220.586.

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In this paper, the analytical formulations among the damping factor and the other parameters are studied by Melnikov method for the classic second-order model of power system. The proximity of Melnikov method is analyzed by comparison between the obtained critical damping factor with the result by time-domain simulation method. It points out that this method exist great error in the range of engineering application. To solve this problem, an improved method is proposed to calculate the critical damping factor based on RBFNN. Finally, simulations show that it can effectively improve the calculation accuracy.

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3

Jin, Ge, Shu Chang Liu, and Ding Cai. "Research of Turbine Model Accuracy Based on Actual Data." Advanced Materials Research 960-961 (June 2014): 1424–28. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1424.

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In the present power system stability analysis, BPA model for turbine and governor is commonly used. It simplifies the actual turbine system to a large extent, therefore the model simulation results may deviate from the actual conditions. In order to improve the actual data simulation accuracy, this paper compared the real and simulation data of power, high pressure cylinder (HPC) exhaust pressure and reheat pressure. Then calibrated and optimized the established model using the data of field operation. Meanwhile, the model modified method using actual data is given and guidance of parameters tests is offered.

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4

Li, Lan, Yong Hui He, and Bo Wang. "Comparison of Methods of Maximum Power Point Tracking of Photovoltaic Cells." Applied Mechanics and Materials 380-384 (August 2013): 3362–65. http://dx.doi.org/10.4028/www.scientific.net/amm.380-384.3362.

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According to engineering mathematics model of solar photovoltaic cells, a simulation model of photovoltaic cells was established in Matlab. In view of problem that it is difficult to get higher tracking accuracy and response speed by use of perturbation and observation method which applied fixed perturbation step, the paper proposed an improved perturbation and observation method based on variable step. Through simulating photovoltaic cells control system, simulation curves of two kinds of methods of maximum power point tracking were compared. The simulation results show that the photovoltaic cells control system can track maximum power point more quickly and has better stability at the maximum power point by use of the improved perturbation and observation method.

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5

Tant, Jeroen, and Johan Driesen. "On the Numerical Accuracy of Electromagnetic Transient Simulation With Power Electronics." IEEE Transactions on Power Delivery 33, no. 5 (October 2018): 2492–501. http://dx.doi.org/10.1109/tpwrd.2018.2797259.

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6

Frivaldsky, Michal, Jan Morgos, Michal Prazenica, and Kristian Takacs. "System Level Simulation of Microgrid Power Electronic Systems." Electronics 10, no. 6 (March 10, 2021): 644. http://dx.doi.org/10.3390/electronics10060644.

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In this paper, we describe a procedure for designing an accurate simulation model using a price-wised linear approach referred to as the power semiconductor converters of a DC microgrid concept. Initially, the selection of topologies of individual power stage blocs are identified. Due to the requirements for verifying the accuracy of the simulation model, physical samples of power converters are realized with a power ratio of 1:10. The focus was on optimization of operational parameters such as real-time behavior (variable waveforms within a time domain), efficiency, and the voltage/current ripples. The approach was compared to real-time operation and efficiency performance was evaluated showing the accuracy and suitability of the presented approach. The results show the potential for developing complex smart grid simulation models, with a high level of accuracy, and thus the possibility to investigate various operational scenarios and the impact of power converter characteristics on the performance of a smart gird. Two possible operational scenarios of the proposed smart grid concept are evaluated and demonstrate that an accurate hardware-in-the-loop (HIL) system can be designed.

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7

Pollmeier, K., C. R. Burrows, and K. A. Edge. "Partitioned Simulation of Fluid Power Systems—an Approach for Reduced Communication between Processors." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 210, no. 4 (November 1996): 221–30. http://dx.doi.org/10.1243/pime_proc_1996_210_461_02.

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Parallel simulation of fluid power systems using the transmission line modelling method offers the benefit of increased speed of execution, but requires the system model to be partitioned on to individual processors. Fluid power systems are characterized by a transport delay in the pipelines connecting physical components, which allows component models to be decoupled; this leads to simulations involving frequent interprocessor communication and low computational performance. This paper describes a method that enables faster simulations by reducing the communication bottleneck. By adjusting the line impedance it is possible to use a larger time step for the communication between processors than the global time step. This approach requires a new filter for the approximation of frequency-dependent friction. Potential gains and the accuracy of the method are estimated. A hydraulic example circuit is partitioned in two subsystems and the new scheme leads to valuable reductions in run time without compromising accuracy.

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8

Malik, N. H., and A. A. Al-Arainy. "Capacitance Calculation of Three Core Belted Power Cables." International Journal of Electrical Engineering & Education 25, no. 1 (January 1988): 27–32. http://dx.doi.org/10.1177/002072098802500107.

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Based on charge simulation technique for solving the electrostatic field problems, a method to compute the capacitance of three core belted power cables is discussed. It is shown that very accurate capacitance calculations are possible if an appropriate number of simulating charges are used. Furthermore, the factors which influence the accuracy of such computations are analyzed.

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9

Dinkelbach, Jan, Ghassen Nakti, Markus Mirz, and Antonello Monti. "Simulation of Low Inertia Power Systems Based on Shifted Frequency Analysis." Energies 14, no. 7 (March 27, 2021): 1860. http://dx.doi.org/10.3390/en14071860.

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New types of power system transients with lower time constants are emerging due to the replacement of synchronous generation with converter interfaced generation and are challenging the modeling approaches conventionally applied in power system simulation. Quasi-stationary simulations are based on classical phasor models, whereas EMT simulations calculate the instantaneous values of models in the time domain. In addition to these conventional modeling approaches, this paper investigates simulation based on dynamic phasor models, as has been proposed by the Shifted Frequency Analysis. The simulation accuracy of the three modeling approaches was analyzed for characteristic transients from the electromagnetic to the electromechanical phenomena range, including converter control as well as low inertia transients. The analysis was carried out for systems with converter interfaced and synchronous generation whilst considering the simulation step size as a crucial influence parameter. The results show that simulations based on dynamic phasors allow for larger step sizes than simulations that calculate the instantaneous values in the time domain. This can facilitate the simulation of more complex component models and larger grid sizes. In addition, with dynamic phasors, more accurate simulation results were obtained than with classical phasors, in particular—but not exclusively—in a low inertia case. Overall, the presented work demonstrates that dynamic phasors can enable fast and accurate simulations during the transition to low inertia power systems.

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10

Nohacova, Lucie, and Karel Nohac. "Dynast – Computer Program Used in Power Engineering." Applied Mechanics and Materials 284-287 (January 2013): 1035–38. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.1035.

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There are relatively insufficient quality specialized modeling tools for power engineering. Regardless there are few possibilities how to simulate main elements of electric network and systems consisting of them. Beside most used specialized tool EMTP-ATP there is MATLAB with its Simulink library SimPowerSystems and newly also DYNAST with its own growing library of power engineering elements. There are also many other general simulation tools with libraries of elements suitable for power engineering. Therefore there seems to be opportunity to compare quality of mentioned tools in accuracy, reliability, speed and flexibility in high demanding problems. Branch “Power engineering” is very specific, because there is necessary in most cases to simulate multiple technical disciplines. Not only electrical network is to solve, but also connection with mechanical equipment and other devices of power engineering. One of the most powerful tools that meet all these requirements is Dynast. Now new library for electric components was developed to make creation of model easy and fast.

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11

Bao, Hai, Xin Huang, Ling Wang, and Gang Liu. "A New Method for Online Steady-State Power Flow Calculation in Electric Power System." Advanced Materials Research 816-817 (September 2013): 1090–93. http://dx.doi.org/10.4028/www.scientific.net/amr.816-817.1090.

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Owing to the given variables are measurable in online power flow calculation, the electrical variables of higher measuring accuracy should be chosen for calculation. Currently the theory of reactive power is deficient and several methods for reactive power measurement are briefly introduced in this paper. The inaccuracy of those methods is pointed out by the relevant references in non-sinusoidal conditions. The measuring accuracy of Active power directly obtained by voltage and current is the same as that of voltage and current. For increasing the accuracy of online power flow calculation, a method substituting voltage magnitude for reactive power is proposed in this paper. The new method eliminates the effects resulted from inaccurate reactive power measurement. The simulation results on software MATPOWER verify the correctness and rationality of the new method.

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12

Zha, Fengwei. "Research on transient simulation model of high power diode for commutating over-voltage." Modern Physics Letters B 32, no. 34n36 (December 30, 2018): 1840078. http://dx.doi.org/10.1142/s021798491840078x.

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Large transient surges called commutating over-voltage may be generated during the reverse recovery process of diode, which poses a severe threat to the system reliability. However, the commutating over-voltage theoretical calculations are so complicated that it is inconvenient to apply to engineering practice. The characteristics of diode commutating over-voltage are studied by using transient model simulation method. The diode simulation model including reverse recovery characteristics is created by adding a resistance, an inductance and a controlled current source to a common diode simulation model. By taking 1 kV/120 kA DC test system as the research object, the simulation model is created and a commutating over-voltage experiment has been carried out, the relative error between simulation value and measured value is within 8%. It turns out that the transient simulation model not only meets engineering accuracy requirement but also avoids complicated calculations.

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13

Schnös, Florian, Dirk Hartmann, Birgit Obst, and Glenn Glashagen. "GPU accelerated voxel-based machining simulation." International Journal of Advanced Manufacturing Technology 115, no. 1-2 (May 8, 2021): 275–89. http://dx.doi.org/10.1007/s00170-021-07001-w.

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AbstractThe simulation of subtractive manufacturing processes has a long history in engineering. Corresponding predictions are utilized for planning, validation and optimization, e.g., of CNC-machining processes. With the up-rise of flexible robotic machining and the advancements of computational and algorithmic capability, the simulation of the coupled machine-process behaviour for complex machining processes and large workpieces is within reach. These simulations require fast material removal predictions and analysis with high spatial resolution for multi-axis operations. Within this contribution, we propose to leverage voxel-based concepts introduced in the computer graphics industry to accelerate material removal simulations. Corresponding schemes are well suited for massive parallelization. By leveraging the computational power offered by modern graphics hardware, the computational performance of high spatial accuracy volumetric voxel-based algorithms is further improved. They now allow for very fast and accurate volume removal simulation and analysis of machining processes. Within this paper, a detailed description of the data structures and algorithms is provided along a detailed benchmark for common machining operations.

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14

Li, Hangyu, Jeroen C. Vink, and Faruk O. Alpak. "An Efficient Multiscale Method for the Simulation of In-situ Conversion Processes." SPE Journal 20, no. 03 (June 15, 2015): 579–93. http://dx.doi.org/10.2118/172498-pa.

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Summary Numerical modeling of the in-situ conversion process (ICP) is a challenging endeavor involving thermal multiphase flow, compositional pressure/volume/temperature (PVT) behavior, and chemical reactions that convert solid kerogen into light hydrocarbons, which are tightly coupled to temperature propagation. Our investigations of grid-resolution effects on the accuracy and performance of ICP simulations have demonstrated that ICP-simulation outcomes—specifically, chemical-reaction rates, kerogen-accumulation profiles, and oil-/gas-production rates, may exhibit relatively large errors on coarse grids. Coarse grids are attractive because they deliver favorable computational performance. We have developed a novel multiscale modeling method for simulating ICP that reduces numerical-modeling errors and reproduces fine-scale-simulation results on relatively coarse grids. The method uses a two-scale solution method, in which the reaction kinetics of the solids is solved locally on a fine-scale grid, with interpolated temperatures obtained from coarse-grid simulations of thermal flow and fluid transport. We demonstrate the accuracy and efficiency of our multiscale method with representative 1D models. It is shown that the method delivers accurate solutions for key ICP performance indicators with very little computational overhead compared with corresponding coarse-scale models. The robustness of the multiscale method has been verified over a number of physical-parameter ranges with a limited-scope sensitivity study. Numerical results show that the multiscale method consistently improves the simulation results and matches the fine-scale reference results closely.

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15

Prieto, J. I., J. Fano, C. González, M. A. González, and R. Diaz. "Preliminary design of the kinematic Stirling engine using dynamic similarity and quasi-static simulation." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 211, no. 3 (March 1, 1997): 229–38. http://dx.doi.org/10.1243/0954406971521809.

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This paper presents a preliminary design method based on dynamic similarity and quasistatic simulation. The proposal improves methods based on Beale and West correlations and provides the engine speeds corresponding to the maximum indicated powers and the achievement of indicated power maps. The dimensionless factor of indicated power losses provides a new viewpoint for engine analysis and design. In support of the method, experimental GPU-3 test results have been reanalysed, proving the accuracy of maximum indicated power predictions and providing values of the dimensionless factor of indicated power losses. Scaling factors corresponding to strict dynamic similarity are supplied for several typical cases. Similarity relaxation criteria are also recommended to be used when strict dynamic similarity leads to inadequate specifications for the derivative. Some numerical examples illustrate the method.

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16

Song, Yan Dong. "Simulation of Average Model Switch Network of Power Converter." Advanced Materials Research 145 (October 2010): 537–40. http://dx.doi.org/10.4028/www.scientific.net/amr.145.537.

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The power converter connected to energy source and linear electric generator is crucial powertrain and converting component, and it is mainly used in hybrid electric vehicle. For switching the states of release energy and absorb energy quickly and smoothly, the accuracy of converter model is very important for designing of control system. The performances of converter can be evaluated by modeling and simulation before produce actual circuitry, so the converter model is created in average model switch network. Simulation results have a distinction between the two models with average model switch network and state equations separately. In comparison the average model switch network is more identical to practical system, so it is more valid for guiding design of control system of converter.

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17

Sadeghkhani, Iman, Abbas Ketabi, and Rene Feuillet. "Investigation of Transmission Line Models for Switching Overvoltages Studies." International Journal of Emerging Electric Power Systems 14, no. 3 (June 19, 2013): 231–38. http://dx.doi.org/10.1515/ijeeps-2012-0004.

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Abstract Overvoltages caused by switching operation of power system equipments might damage some equipment and delay power system restoration. This paper presents a comparison between transmission line (TL) models for overvoltages study and investigates which TL model is most proper for every case study. Both simulation time and accuracy factors of TL models are considered for selecting best TL model. Various cases of switching of transformer, shunt reactor, capacitor bank, and transmission line are investigated and simulation results for a partial of 39-bus New England test system, ‎show that the proposed TL model evaluation increase accuracy and reduce simulation time (accelerate power system restoration) properly.

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18

Zhuge, W., Y. Zhang, X. Zheng, M. Yang, and Y. He. "Development of an advanced turbocharger simulation method for cycle simulation of turbocharged internal combustion engines." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 223, no. 5 (May 1, 2009): 661–72. http://dx.doi.org/10.1243/09544070jauto975.

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An advanced turbocharger simulation method for engine cycle simulation was developed on the basis of the compressor two-zone flow model and the turbine mean-line flow model. The method can be used for turbocharger and engine integrated design without turbocharger test maps. The sensitivities of the simulation model parameters on turbocharger simulation were analysed to determine the key modelling parameters. The simulation method was validated against turbocharger test data. Results show that the methods can predict the turbocharger performance with a good accuracy, less than 5 per cent error in general for both the compressor and the turbine. In comparison with the map-based extrapolation methods commonly used in engine cycle simulation tools such as GT-POWER®, the turbocharger simulation method showed significant improvement in predictive accuracy to simulate the turbocharger performance, especially in low-flow and low-operating-speed conditions.

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19

Yan, Qun Min, and Juan Juan Zhu. "Design and Simulation Analysis of Aircraft Dynamic System." Advanced Materials Research 314-316 (August 2011): 511–17. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.511.

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Aircraft dynamic systems digital simulation platform modeling was construct based on engineering needs and provide the basis of experimental data. Combined with dynamic system characteristics and saber software characteristics .In the Saber simulation software, used the schematic-based, based on functional requirements and the modeling method based on experimental data to establish a dynamic system of different parts of the device model, and according to different modeling methods established by the electrical load model and control model of power systems consisting of mixed-signal model. Finally, experimental verification of the whole system model, simulation results compared with the experimental results prove the accuracy of the system model, effective and practical.

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20

Chen, Guan Yi, Guo Dong Yuan, Le Yu Zheng, Xiao Ke Guo, An Long Lv, Ye Geng, Zhan Zhong Cui, et al. "Analysis of Flow in Power Plant Flue via Fluent Simulations." Advanced Materials Research 838-841 (November 2013): 2630–33. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.2630.

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The gas flow status including velocity and pressure in the rectangular gas duct (before or after) electrostatic precipitator of a power plant were simulated using Fluent software. The grid accuracy which is required by simulation has been determined then the gas flow status has been analyzed through the comparison between numerical simulation results and empirical calculation results. The results show that flues inner supporting structures are the main factor of gas pressure drops and outlet velocity distrubution.

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21

He, Jie, and Fei Zheng. "Dynamics Simulation of Simplified Solar Power Satellite Model on Highly Elliptical Orbit." Advanced Materials Research 953-954 (June 2014): 12–15. http://dx.doi.org/10.4028/www.scientific.net/amr.953-954.12.

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In recent years, with the improvement of the level of development and modernization of industry, more energy is needed, so the desire for clean new energy is growing. Solar energy is undoubtedly the most watched in many types of new energy. Solar Power Satellite (SPS) as a major program has been highly anticipated since it's proposed. Studies have been considering it as for a circular orbit. But there are some disadvantages on circular orbit such as inefficiency and complexity of the transmission link. So it is very important to research the SPS on highly elliptical orbit. In this paper, firstly, a particle - cylinder model is established. Then, dynamics simulation of Solar Power Satellite on highly elliptical orbit is based on this model. The simulations about mature orbit verify the feasibility and accuracy of the model. So this method provides a valuable reference for Solar Power Satellite deployment.

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22

Nagarjuna, Vasili B. V., R. Vishnu Vardhan, and Christophe Chesneau. "On the Accuracy of the Sine Power Lomax Model for Data Fitting." Modelling 2, no. 1 (February 13, 2021): 78–104. http://dx.doi.org/10.3390/modelling2010005.

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Every day, new data must be analysed as well as possible in all areas of applied science, which requires the development of attractive statistical models, that is to say adapted to the context, easy to use and efficient. In this article, we innovate in this direction by proposing a new statistical model based on the functionalities of the sinusoidal transformation and power Lomax distribution. We thus introduce a new three-parameter survival distribution called sine power Lomax distribution. In a first approach, we present it theoretically and provide some of its significant properties. Then the practicality, utility and flexibility of the sine power Lomax model are demonstrated through a comprehensive simulation study, and the analysis of nine real datasets mainly from medicine and engineering. Based on relevant goodness of fit criteria, it is shown that the sine power Lomax model has a better fit to some of the existing Lomax-like distributions.

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23

Li, Defang, Hao Zhang, Hui Yan, Xingjun Tian, Nanqing Wang, and Zexuan Yuan. "Research on Fault Location for Direct Traction Network." Journal of Physics: Conference Series 2215, no. 1 (February 1, 2022): 012020. http://dx.doi.org/10.1088/1742-6596/2215/1/012020.

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Abstract In view of the low accuracy of existing fault location methods for traction networks with longer power supply lines, the equivalent model of the traction network for double-track electrified railways is calculated, and the power supply lines and contacts are introduced on the basis of traditional traction network fault location methods. The parameter of grid equivalent impedance ratio proposes a modified uplink and downlink current ratio ranging method, which effectively solves the problem of accurate fault location of the double-track electrified railway direct-supply traction network. The RT-plus smart grid real-time digital simulation instrument is used to establish the traction power supply dynamics. The simulation test system is simulated and tested, and the test results show that the proposed algorithm has good feasibility and accuracy, and fully meets the engineering requirements.

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24

Zhang, Ying, Shuhai Feng, and Jun Liu. "Practical Analysis of State Estimation Based on Dispatching Simulation Platform." Advanced Materials Research 960-961 (June 2014): 1554–61. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1554.

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In the process of practical application of state estimation in the actual dispatching system, there are many factors that affect the accuracy of state estimation results. This paper based on the simulation platform of the dispatching system and used the operation data of the actual power grid to simulate the operation of power grid, then analyzed the various factors that have influence on the results of state estimation, which provided effective technical support for practical application of state estimation.

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25

Fang, D. Z., Wang Liwei, T. S. Chung, and K. P. Wong. "New techniques for enhancing accuracy of EMTP/TSP hybrid simulation." International Journal of Electrical Power & Energy Systems 28, no. 10 (December 2006): 707–11. http://dx.doi.org/10.1016/j.ijepes.2006.03.012.

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26

Ketabi, A., M. Khoshkholgh, and R. Feuillet. "A New Approach to Nonsinusoidal Steady-State Power System Analysis." Mathematical Problems in Engineering 2009 (2009): 1–18. http://dx.doi.org/10.1155/2009/584637.

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A new analysis method using wavelet domain for steady-state operating condition of power system is developed and introduced. Based on wavelet-Galerkin theory, the system components such as resistor, inductor, capacitor, transmission lines, and switching devices are modeled in discrete wavelet domain for the purpose of steady-state analysis. To solve system equations, they are transferred to wavelet domain by forming algebraic matrix-vector relations using the wavelet transform coefficients and the equivalent circuit is thus built for system simulation. After describing the new algorithm, two-case studies are presented and compared with the simulations in the time domain to verify the accuracy and computational performance.

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27

Dai, Meng. "Doubly-Fed Wind Farm Engineering Aggregation Model Used for Planning." Advanced Materials Research 986-987 (July 2014): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.291.

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Establishing an appropriate aggregation model of wind farm is the first step of the electrical computation in wind power integration planning. This paper first summarizes the technical requirements of wind farm model from the viewpoint of engineering, then proposes an aggregation DFIG model of wind farm. Because of the lack of measured data in the planning stage, the single equivalent model is used in this paper, and be improved by considering the equivalent collection lines model. The accuracy of the aggregation model in different electrical calculation, such as power flow, transient stability and shortcut current simulation, is verified through a sample system in DIgSILENT.

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28

Upamanyu, Kapil, and G. Narayanan. "Improved Accuracy, Modeling, and Stability Analysis of Power-Hardware-in-Loop Simulation With Open-Loop Inverter as Power Amplifier." IEEE Transactions on Industrial Electronics 67, no. 1 (January 2020): 369–78. http://dx.doi.org/10.1109/tie.2019.2896093.

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29

Abramovitz, Alexander. "Comparison of Duty Cycle Generator Algorithms for SPICE Simulation of SMPS." Advances in Power Electronics 2012 (May 31, 2012): 1–8. http://dx.doi.org/10.1155/2012/574289.

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The paper presents and discusses an algorithm for average modeling of the PWM modulator in switch-mode power systems by general purpose electronic circuit simulators such as PSPICE. A comparison with previous theoretical models is conducted. To test the accuracy of the average PWM models comparison to cycle-by-cycle simulation was conducted. The proposed algorithm shows better accuracy than earlier counterparts.

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30

Tsai, Wei-Chang, and C. Bernard Shung. "Event-Driven Power Estimation of CMOS Circuits." Journal of Circuits, Systems and Computers 07, no. 05 (October 1997): 471–82. http://dx.doi.org/10.1142/s0218126697000358.

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Fast and accurate power estimation has become an important topic with the increasing need for low power electronics. In this paper we address the problem of using event-driven simulation tools for power estimation. We identify and compare two approaches: input-driven and output-driven, and propose several ways of improvement. The estimation accuracy is degraded in event-driven power estimators due to superfluous and partial glitches. We described glitch filtering and estimation techniques pertaining to input-driven and output-driven power estimators. An output-driven power estimator, Peony, was developed which used the proposed path power idea to improve the estimation accuracy. It achieved significant power estimation accuracy improvement at a speed of two orders of magnitude faster than Spice.

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31

Li, Yun Long, Chang Lu Zhao, Yang Yang Liu, Qian Peng, and Chang Jiang Li. "The Research of the Power Capsule Fan Energy Consumption in Thermal Balance Test Method." Applied Mechanics and Materials 490-491 (January 2014): 902–9. http://dx.doi.org/10.4028/www.scientific.net/amm.490-491.902.

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The research makes a heat balance test for the radiator system of the analog power capsule. And it also raises a correction calculation method of the fan in the closed cooling heat balance system for special vehicle and proves it by simulation. The research setting up the simulation test bed of the cooling system, conducting the heat balance test and verifying the validity of the carload test bed. Finally, the closed cooling air volume control precision and accuracy of the measurement system can meet the requirements of engineering application

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Liu, Dun Nan, Yu Hu, Qun Li, Guang Hui Shao, Hai Ming Zhou, and Dan Li. "Regional Wind Power Forecasting Based on Cloud Model and Wind Rate Vector." Advanced Materials Research 860-863 (December 2013): 405–8. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.405.

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The accuracy of wind power forecast is important to the power system operation. A new prediction model is proposed based on cloud reasoning and wind rate vector , combining with the current and the historical change rule of wind speed, using the change rule of wind speed in a period of time to forecast the power gradient in a point-in-time, The wind turbine power prediction is discussed based on power gradient and power eigenvalue. Simulation results on the case study of historical wind speed and generated power data in some area in China demonstrate that the proposed methodology can improve the accuracy of wind speed forecast and has practical value, especially for the wind turning point.

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33

Ma, Shi Jun, Hao Wang, Jian She Tian, and Li Meng. "Research on Analysis and Control Strategy of High Frequency Phenomenon in an Isolated Power Grid." Advanced Materials Research 694-697 (May 2013): 2073–79. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.2073.

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An operation and control simulation platform for isolated power grid are set up, which is based on the detailed models of the boiler, turbine, Coordinated Control System (CCS), Digital Electric-hydraulic Control system (DEH), Overspeed Protection Controller (OPC) and so on. By means of simulation, the accuracy of this platform is verified and the cause leading to high frequency of the isolated power grid is proposed..In addition, the control strategy for high frequency of isolated power grid based on wide area measurement data is proposed.

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34

Dghais, Wael, Malek Souilem, Fakhreddine Zayer, and Abdelkader Chaari. "Power Supply- and Temperature-Aware I/O Buffer Model for Signal-Power Integrity Simulation." Mathematical Problems in Engineering 2018 (August 8, 2018): 1–9. http://dx.doi.org/10.1155/2018/1356538.

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This paper presents the development and evaluation of a large-signal equivalent circuit model that accounts for the power supply fluctuation and temperature variation of I/O buffers circuit designed based on the fully depleted silicon on insulator (FDSOI) 28 nm process for signal-power integrity (SPI) simulation. A solid electrical analysis based on the working mechanisms of the nominal I/O buffer information specification- (IBIS-) like model is presented to support the derivation of an accurate and computationally efficient behavioral model that captures the essential effects of the power supply bouncing under temperature variation. The formulation and extraction of the Lagrange interpolating polynomial are investigated to extend the nominal equivalent circuit model. The generated behavioral model is implemented using the Newton-Neville’s formula and validated in simultaneous switching output buffers (SSO) scenario under temperature variation. The numerical results show a good prediction accuracy of the time domain voltage and current waveforms as well as the eye diagram of the high-speed communication I/O link while speeding-up the transient simulation compared to the transistor level model.

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35

Oboskalov, Vladislav Petrovich, Irina Lvovna Kirpikova, Stanislava Matugova, and Sergey Aleksandrovich Gusev. "Supplied Demand Technique for Power System Balance Reliability Calculations." Advanced Materials Research 960-961 (June 2014): 1512–15. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1512.

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This paper presents an iterative power system balance reliability calculating technique ensuring better convergence and faster calculations. The technique is called "supplied demand". Nodal power imbalance is considered as the primary stochastic value under analysis. An analytical solution does not contain probability density functions. It results in faster calculations. Results were verified by Monte Carlo Simulation and showed high accuracy of the technique.

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36

Zhong, Qian Wen, Yang Xu, Jie Yang, and Zhuo Meng. "PV Array Mathematical Model Optimization Based on Monitoring Data." Applied Mechanics and Materials 376 (August 2013): 336–40. http://dx.doi.org/10.4028/www.scientific.net/amm.376.336.

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The type of Solar panels in photovoltaic power generating system is generally photovoltaic array. On the basis of the photovoltaic array mathematical model for engineering , using the mathematical software MATLAB Simulink tool to build a photovoltaic array simulation model and utilizing monitoring data acquired by the detection system-Sunny Sensor Box-for Donghua University photovoltaic power generating system, the mathematical model of the PV array for engineering is optimized and the optimization includes linear and natural exponential optimization. Furthermore, higher accuracy of the optimized models is validated.

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37

Hong, Miao, Yushi Miura, Toshifumi Ise, Yuki Sato, Toshinari Momose, and Christian Dufour. "Stability and Accuracy Analysis of Power Hardware-in-the-loop Simulation of Inductor Coupled Systems." IEEJ Transactions on Industry Applications 130, no. 7 (2010): 902–12. http://dx.doi.org/10.1541/ieejias.130.902.

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38

Samsonovich, Semen L., Boris K. Fedotov, Nikolay B. Rozhnin, and Roman V. Goryunov. "Results of research on backlash compensation in a power electric drive by low-power electronic device." Acta Polytechnica 62, no. 2 (May 5, 2022): 303–12. http://dx.doi.org/10.14311/ap.2022.62.0303.

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This article considers the feasibility of restoring and maintaining the kinematic accuracy of the support-rotary device drives by introducing a backlash compensation device into the control system. The power electromechanical drives of support-rotary device considered in this article contain two motors, the summation of the torques of which is carried out on a common output shaft. It is shown that the restoration of the required kinematic accuracy of the drives can be achieved by introducing one of two variants of an electronic device for backlash compensation into the control system. In the first variant, equal and opposite displacement signals are introduced into the control signals of the motors. The second variant introduces an electronic cross-connections backlash compensation scheme was into the control system. The study of the operation of the support-rotary device drive system with two backlash compensation devices carried out by a simulation method showed that the use of a cross-connection scheme is the most preferable and effective.As a result of the research, it was shown that the introduction of an electronic backlash compensation device into the control system makes it possible to ensure the operability of the power electromechanical drives of a support-rotary device with initial kinematic accuracy.

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39

Vidović, Danko, Elis Sutlović, and Matislav Majstrović. "A Unique Electrical Model for the Steady-State Analysis of a Multi-Energy System." Energies 14, no. 18 (September 13, 2021): 5753. http://dx.doi.org/10.3390/en14185753.

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In order to decarbonize the energy sector, the interdependencies between the power and natural gas systems are going to be much stronger in the next period. Thus, it is necessary to have a powerful simulation model that is able to efficiently and simultaneously solve all coupled energy carriers in a single simulation environment in only one simulation step. As an answer to the described computational challenges, a unique model for the steady-state analysis of a multi-energy system (MES) using the electrical analogy approach is developed. Detailed electrical equivalent models, developed using the network port theory and the load flow method formulation, of the most important natural gas network elements, as well as of the linking facilities between the power and natural gas systems, are given. The presented models were loaded up into a well-known software for the power system simulation—NEPLAN. In the case studies, the accuracy of the presented models is confirmed by the comparison of the simulation results with the results obtained by SIMONE—a well-known software for natural gas network simulations. Moreover, the applicability of the presented unique model is demonstrated by the MES security of a supply analysis.

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40

Piché, R., and A. Ellman. "Numerical Integration of Fluid Power Circuit Models Using Two-Stage Semi-Implicit Runge-Kutta Methods." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 208, no. 3 (May 1994): 167–75. http://dx.doi.org/10.1243/pime_proc_1994_208_114_02.

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Fluid power circuits that contain fluid volumes of different orders of magnitude are difficult to simulate because the system of ordinary differential equations is numerically stiff. Even algorithms specially designed for stiff systems require excessively small time steps to avoid numerical oscillation in simulations of some circuits. In this paper the accuracy and numerical stability of several two-stage semi-implicit Runge-Kutta methods that have been proposed in circuit simulation literature are analysed and compared. It is shown that, for integration of very stiff circuits, the best method in this class is an L-stable method. A simple numerical example is used to verify the theoretical results. The example includes a novel way of modelling orifice flow that is especially suitable for numerical simulations.

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Alpak, Faruk O., and Jeroen C. Vink. "Adaptive Local-Global Multiscale Simulation of the In-situ Conversion Process." SPE Journal 21, no. 06 (June 8, 2016): 2112–27. http://dx.doi.org/10.2118/173218-pa.

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Summary Numerical modeling of the in-situ conversion process (ICP) is a challenging endeavor involving thermal multiphase flow, compositional pressure/volume/temperature (PVT) behavior, and chemical reactions that convert solid kerogen into light hydrocarbons and are tightly coupled to temperature propagation. Our investigations of grid-resolution effects on the accuracy and performance of ICP simulations demonstrated that ICP-simulation outcomes (e.g., oil/gas production rates and cumulative volumes) may exhibit relatively large errors on coarse grids, where “coarse” means a gridblock size of more than 3 to 5 m. On the other hand, coarse-scale models are attractive because they deliver favorable computational performance, especially for optimization and uncertainty quantification workflows that demand a large number of simulations. Furthermore, field-scale models become unmanageably large if gridblock sizes of 3 to 5 m or less have to be used. Therefore, there is a clear business need to accelerate the ICP simulations with minimal compromise of accuracy. We developed a novel multiscale-modeling method for ICP that reduces numerical-modeling errors and approximates the fine-scale simulation results on relatively coarse grids. The method uses a two-scale adaptive local-global solution technique. One global coarse-scale and multiple local fine-scale near-heater models are timestepped in a sequentially coupled fashion. At a given global timestep, the global-model solution provides accurate boundary conditions to the local near-heater models. These boundary conditions account for the global characteristics of the thermal-reactive flow and transport phenomena. In turn, fine-scale information about heater responses is upscaled from the local models, and used in the global coarse-scale model. These flow-based effective properties correct the thermal-reactive flow and transport in the global model either explicitly, by updating relevant coarse-grid properties for the next timestep, or implicitly, by repeatedly updating the properties through a convergent iterative scheme. Upon convergence, global coarse-scale and local fine-scale solutions are compatible with each other. We demonstrate the much-improved accuracy and efficiency delivered by the multiscale method by use of a 2D cross-section pattern-scale ICP simulation problem. The following conclusions are reached through numerical testing: (1) The multiscale method significantly improves the accuracy of the simulation results over conventionally upscaled models. The method is particularly effective in correcting the global coarse-scale model through the use of the fine-scale information about heater temperatures to regulate the heat-injection rate into the formation more accurately. The effective coarse-grid properties computed by the multiscale method at every timestep also enhance the accuracy of the ICP simulations, as demonstrated in a dedicated test case, in which a constant heat-injection rate is enforced across models of all investigated resolutions. (2) Multiscale ICP models result in accelerated simulations with a speed-up of four to 16 times with respect to fine-scale models “out of the box” without any special optimization effort. (3) Our multiscale method delivers high-resolution solutions in the vicinity of the heaters at a reduced computational cost. These fine-scale solutions can be used to better understand the evolution of the fluids and solids (e.g., kerogen conversion and coke deposition) in the vicinity of the heaters (several-feet-long spatial scale). Simultaneously, with the fine-scale near-heater solutions, the local-global coupled multiscale model provides key commercial ICP performance indicators at the pattern scale (several-hundred-feet-long spatial scale) such as production functions.

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42

Yang, Zhixi, Xianbin Li, and Jun Yang. "Power Efficient and High-Accuracy Approximate Multiplier with Error Correction." Journal of Circuits, Systems and Computers 29, no. 15 (June 30, 2020): 2050241. http://dx.doi.org/10.1142/s0218126620502412.

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Approximate arithmetic circuits have been considered as an innovative circuit paradigm with improved performance for error-resilient applications which could tolerant certain loss of accuracy. In this paper, a novel approximate multiplier with a different scheme of partial product reduction is proposed. An analysis of accuracy (measured by error distance, pass rate and accuracy of amplitude) as well as circuit-based design metrics (power, delay and area, etc.) is utilized to assess the performance of the proposed approximate multiplier. Extensive simulation results show that the proposed design achieves a higher accuracy than the other approximate multipliers from the previous works. Moreover, the proposed design has a better performance under comprehensive comparisons taking both accuracy and circuit-related metrics into considerations. In addition, an error detection and correction (EDC) circuit is used to correct the approximate results to accurate results. Compared with the exact Wallace tree multiplier, the proposed approximate multiplier design with the error detection and correction circuit still has up to 15% and 10% saving for power and delay, respectively.

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43

Nzale, Willy, Jean Mahseredjian, Xiaopeng Fu, Ilhan Kocar, and Christian Dufour. "Accurate time-domain simulation of power electronic circuits✰." Electric Power Systems Research 195 (June 2021): 107156. http://dx.doi.org/10.1016/j.epsr.2021.107156.

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44

Aouchiche, N., M. Becherif, A. HadjArab, M. S. Aitcheikh, H. S. Ramadan, and A. Cheknane. "Dynamic Performance Comparison for MPPT-PV Systems using Hybrid Pspice/Matlab Simulation." International Journal of Emerging Electric Power Systems 17, no. 5 (October 1, 2016): 529–39. http://dx.doi.org/10.1515/ijeeps-2016-0074.

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Abstract The power generated by solar photovoltaic (PV) module depends on the surrounding irradiance and temperature. This paper presents a hybrid Matlab™/Pspice™ simulation model of PV system, combined with Cadence software SLPS. The hybridization is performed in order to gain the advantages of both simulation tools such as accuracy and efficiency in both Pspice electronic circuit and Matlab™ mathematical modelling respectively. For this purpose, the PV panel and the boost converter are developed using Pspice™ and hybridized with the mathematical Matlab™ model of maximum power point method controller (MPPT) through SLPS. The main objective is verify the significance of using the proposed hybrid simulation techniques in comparing the different MPPT algorithms such as the perturbation and observation (P&O), incremental of conductance (Inc-Cond) and counter reaction voltage using pilot cell (Pilot-Cell). Various simulations are performed under different atmospheric conditions in order to evaluate the dynamic behaviour for the system under study in terms of stability, efficiency and rapidity.

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45

Kang, S. M. "Accurate simulation of power dissipation in VLSI circuits." IEEE Journal of Solid-State Circuits 21, no. 5 (October 1986): 889–91. http://dx.doi.org/10.1109/jssc.1986.1052622.

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46

Zhu, Darui, Haifeng Wang, Rui Wang, Jiandong Duan, and Jing Bai. "Identification of Key Nodes in a Power Grid Based on Modified PageRank Algorithm." Energies 15, no. 3 (January 22, 2022): 797. http://dx.doi.org/10.3390/en15030797.

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For avoiding the occurrence of large-scale blackouts due to disconnected nodes in the power grid, a modified PageRank algorithm is proposed to identify key nodes by integrating the topological information and node type. The node betweenness index is first introduced based on complex network theory, which is modified to reflect the node topological information in the power grid. Then, according to the characteristics of different node types in the power grid, a modified PageRank algorithm is proposed to rapidly identify key nodes, which takes the generator nodes, load nodes, and contact nodes into account. IEEE 39-Bus system and IEEE 118-Bus system are used for the simulations. Simulation results showed that the network transmission efficiencies of the power grid are reduced from 64.23% to 5.62% and from 45.4% to 5.12% in the two simulation systems compared with other methods. The proposed identification algorithm improved the accuracy, and a provincial power grid simulation system in China is used to verify the feasibility and validity. The identified nodes are removed, which split the power grid according to importance index values. The proposed method in this paper is helpful to prevent the occurrence of cascading failure in the power system, and it can also be used to power systems with renewable energy sources and an AC/DC hybrid power grid.

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Guo, Huaixin, Tangsheng Chen, and Shang Shi. "Transient Simulation for the Thermal Design Optimization of Pulse Operated AlGaN/GaN HEMTs." Micromachines 11, no. 1 (January 9, 2020): 76. http://dx.doi.org/10.3390/mi11010076.

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The thermal management and channel temperature evaluation of GaN power amplifiers are indispensable issues in engineering field. The transient thermal characteristics of pulse operated AlGaN/GaN high electron mobility transistors (HEMT) used in high power amplifiers are systematically investigated by using three-dimensional simulation with the finite element method. To improve the calculation accuracy, the nonlinear thermal conductivities and near-junction region of GaN chip are considered and treated appropriately in our numerical analysis. The periodic transient pulses temperature and temperature distribution are analyzed to estimate thermal response when GaN amplifiers are operating in pulsed mode with kilowatt-level power, and the relationships between channel temperatures and pulse width, gate structures, and power density of GaN device are analyzed. Results indicate that the maximal channel temperature and thermal impedance of device are considerably influenced by pulse width and power density effects, but the changes of gate fingers and gate width have no effect on channel temperature when the total gate width and active area are kept constant. Finally, the transient thermal response of GaN amplifier is measured using IR thermal photogrammetry, and the correctness and validation of the simulation model is verified. The study of transient simulation is demonstrated necessary for optimal designs of pulse-operated AlGaN/GaN HEMTs.

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48

T R, Nischith, Namita Palecha, and John Alwyn. "Novel Approach to Measure Internal Power Domain PG Route Weakness." Journal of University of Shanghai for Science and Technology 23, no. 05 (June 17, 2021): 704–8. http://dx.doi.org/10.51201/jusst/21/05339.

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Grid weakness measurement is an extremely important process in the modern-day VLSI design flow. In designs that contain power gating switches, there are additional challenges. It is desirable to find the PG grid weakness of only the gated domain. The tools used in the industry typically measure the total voltage drops from the bump location to the transistor pin. This voltage drop is the summation of the voltage drops in the external domain, switch pin network, and internal domain. This paper explores the ways to measure the internal pin domain voltage exclusively. Ansys Totem tool is used for simulation. Finally, the simulation results are presented to propose the effectiveness and accuracy of the given solution.

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49

Chen, Fang, Xi-Lin Dong, Yan Tang, An-Chi Huang, Mei-Lin Zhang, Qing-Chun Kang, Zhong-Jun Shu, and Zhi-Xiang Xing. "Thermal Characteristic Analysis of Sodium in Diluted Oxygen via Thermogravimetric Approach." Processes 10, no. 4 (April 5, 2022): 704. http://dx.doi.org/10.3390/pr10040704.

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As the main reactor type of the fourth-generation nuclear power systems, sodium-cooled fast reactors are now designed and built worldwide. A sodium pool cooling circulation process is indispensable in a sodium-cooled fast reactor. However, the sodium pool fire design is the basis of accidents in sodium-cooled fast reactors. The fire hazard caused by the sodium–oxygen reaction and fast reactor safety have attracted extensive attention. Dry powder is widely used as an effective fire-extinguishing agent to control sodium fire. The sodium will burn in an oxygen-depleted atmosphere when using dry powder to cover fire. In this study, the change law of thermogravimetry of melted sodium is studied by thermogravimetric analysis (TGA) and the apparent activation energy (Ea) is obtained, which has a linear relationship with the oxygen concentration. The results can provide a reference for improving the engineering design standards of sodium fire suppression systems and can also be incorporated into simulation software to improve the accuracy of fire suppression simulations.

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Mallison, Bradley T., Margot G. Gerritsen, and Sebastien F. Matringe. "Improved Mappings for Streamline-Based Simulation." SPE Journal 11, no. 03 (September 1, 2006): 294–302. http://dx.doi.org/10.2118/89352-pa.

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Summary Our interest lies in extending the streamline method to compositional simulation. In this paper, we develop improved mappings to and from streamlines that are necessary to obtain reliable predictions of gas injection processes. Our improved mapping to streamlines uses a piecewise linear representation of saturations on the background grid in order to minimize numerical smearing. Our strategy for mapping saturations from streamlines to the background grid is based on kriging. We test our improvements to the streamline method by use of a simple model for miscible flooding based on incompressible Darcy flow. Results indicate that our mappings offer improved resolution and reduce mass-balance errors relative to the commonly used mappings. Our mappings also require fewer streamlines to achieve a desired level of accuracy. In compositional cases where the computational cost of a streamline solve is high, we anticipate that this will lead to an improvement in the efficiency of streamline-based simulation. Introduction The overall goal of our research is to improve the accuracy and efficiency of the streamline method in simulating compositional problems such as those that occur in miscible or near-miscible gas injection processes. This is our second paper suggesting improvements to this end. In Mallison et al. (2005) we investigated a 1D compositional finite-difference solver based on a high-order upwind scheme and adaptive mesh refinement that is appropriate for use in a compositional streamline simulator. Here, we propose new mappings to and from streamlines that improve the accuracy of the streamline method for problems in which the flow pattern does not remain fixed for large time intervals. Such problems require that streamlines be periodically updated in order to account for changing flow directions and for the treatment of gravity terms (Thiele et al. 1996; Bratvedt et al. 1996). For each set of streamlines, fluids must be mapped from an underlying background grid, on which the pressure is solved (or, say, the flow), to the streamlines, moved forward in time, and then mapped from the streamlines back to the background grid. The mappings introduce numerical smearing and generally also mass-balance errors. When streamlines are updated frequently, the mapping errors limit the overall accuracy of the streamline method. Our improved mapping algorithms are aimed at minimizing this type of error.

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