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Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The detailed model of the back-to-back converter of the permanent magnet direct drive wind power system contains multiple power electronic devices, and the use of pulse width modulation technology will inevitably increase the mathematical calculation of the simulation system. In view of the problem, a mean value model is proposed to simplify the system so that the wind power system can operate quickly and stably. For the converter mean value model, the controlled power supply is used to replace the converter in structure, and its higher harmonics are ignored in principle, and only the fundamental wave component is retained. In addition, from the perspective of system control, the control strategy of the system is improved by removing the PWM modulation process. Finally, a permanent magnet direct drive wind power system simulation model is built in MATLAB/Simulink, and the system response of the mean model and the detailed model are compared. The simulation results show that the mean value model can not only meet the system accuracy requirements, but also speed up the system simulation speed, greatly improve the system stability, which verifies the rationality of the control strategy. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of system frequency stability decreasing caused by the access of renewable energy to the power system, the control strategy of virtual synchronous generator (VSG) is combined with optimization algorithm to propose a VSG control strategy based on algorithm optimization. The Antlion algorithm is improved to optimize the parameters of the VSG and maximize the performance of the VSG. The optimized VSG is used to control the grid -connected inverter. The power system simulation model is established and compared with traditional control scheme. The results show that the optimized VSG control strategy reduces the amplitude and time of system frequency fluctuations, the amplitude of frequency fluctuation under step load disturbance is reduced by about 0.000 42 Hz, and the fluctuation time is reduced by about 1.5 s, which improves the frequency stability of the renewable energy power system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In solving the problem of multi-objective optimization operation of distributed power supply in micro-grid, aiming at the limitations of traditional NSGA-II algorithm in terms of approximation and computational efficiency, considering the difference of individual similarity in evolution process and the possibility of the algorithm falling into local optimum, this paper proposed an improved NSGA-II algorithm. The new algorithm introduced the information entropy mechanism to improve the operator, and approximated the crossover probability and mutation probability as the decreasing function model and the Cauchy distribution model respectively. The performance test proves that the new algorithm is effective. Taking distributed power supply access to IEEE 30-node power system as an example for simulation experiment, compared with the traditional NSGA-II multi-objective optimization algorithm, the result shows the superiority of the improved algorithm in improving the convergence speed and the optimization indices. [ABSTRACT FROM AUTHOR]

In order to carry out research and teaching experiment related to faults in power distribution system, the physical parameters of each component of the physical simulation power distribution system are measured based on the simulation ratios which are derived according to the equivalent principle. Based on the modular idea, the primary and secondary devices are combined into typical functional modules which are interconnected via Ethernet to form the required modular physical simulation experiment system. The monitoring module is used to monitor and control the substation modules, the feeder modules, the ring network cabinet modules, the flexible fault generating modules and the fault recording modules, then, the storage, analysis and management of the data are realized under various working conditions. A model that is consistent with the physical simulation experiment system is built on PSCAD/EMTDC software. The simulation results show that the designed system is feasible and effective. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using the Cuckoo Search Algorithm (CS) to solve the reactive power optimization problem in power systems is a new way. But two of the important parameters are constants which lead to the slow convergence speed in the late iterations, and it is easy to fall into local optimum. Thus, the variations of the two main parameters and an improved step search equation are introduced into the improved Cuckoo Search Algorithm (ICS). In this paper, in order to verify the validity, CS and ICS have been examined and tested in IEEE3.0 bus test system based on MATLAB software. The simulation results show that, using ICS to solve the reactive power optimization problem can minimize power losses, at the same time, improve the convergence performance. The method can improve students' simulation level and promote the understanding of reactive power optimization. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The expert system used in power system fault diagnosis has a long development cycle and can not diagnose the faults beyond experiences. A kind of fault diagnosis of power system was proposed based on model-based diagnosis and skyline query. The diagnosed system was decomposed into several independent subsystems based on the distribution of measurement points. By establishing system models considering the causality between the system failure output and system element， candidate diagnosis of each subsystem was inferred. The actual alarm information was introduced into diagnosis logic framework to identify the fault element from candidate diagnosis by using skyline query. Ready candidate diagnosis was obtained offline and candidate diagnostic was confirmed online based on the proposed method， which saved the time of diagnosis. Actual alarm information was introduced into diagnosis logic framework， which improved the efficiency of diagnosis. The simulation results show that the method can effectively reduce the complexity of time and space. [ABSTRACT FROM AUTHOR]

In accordance with the principles of current protection in relay protection, simulation model of current protection is designed and established with MATLAB/SIMULINK platform. This paper analyzes the function of the modules of the model and their parameters. The simulation result shows that the designed system makes the correct protection operation, which provides effective methods and platforms for the study on current protection. [ABSTRACT FROM AUTHOR]

In accordance with the principles of current protection in relay protection ， simulation model of current protection is designed and established with MATLAB/SIMULINK platform. This paper analyzes the function of the modules of the model and their parameters. The simulation result shows that the designed system makes the correct protection operation，which provides effective methods and platforms for the study on current protection. [ABSTRACT FROM AUTHOR]

This paper presents the use of artificial intelligent technique to study the load frequency control of a two area reheat thermal interconnected power system. In this proposed scheme, a control methodology is developed using Modified Dynamic Neural Network (MDNN) for the design of integral controller. The control strategies found to be guarantee such that the steady state error of frequencies and inadvertent interchange of tie-line power are maintained in a given tolerance limitations. A comparison of the output response of the system with the Proportional-Integral (PI) controller and MDNN controller based approaches shows the superiority of proposed MDNN based approach over PI controller for different loading conditions (1%and 5% step load variations). From the simulation results a comparative performance study in terms of the settling time and peak over shoot of the output response of the system has been tabulated. [ABSTRACT FROM AUTHOR]

To meet the requirements of aircraft tractor, the main parameters of power system were optimized and the optimized results were analyzed by a mathematical model. The braking control system structure and the working policy were designed according to the requirements of regenerated hydraulic braking system. The dual hydraulic braking style was analyzed with consideration of braking conditions greatly influenced by parameter perturbation, so that the optimal working mode was obtained. The control algorithm was proved to be efficient based on the design of ANN fuzzy PID controller and the performance test on the test-bed simulated the hydraulic hybrid tractor. [ABSTRACT FROM AUTHOR]