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Xue Y.,Shanghai University of Electric Power | Wang S.,Jinshan Power Supply Company
Taiyangneng Xuebao/Acta Energiae Solaris Sinica

For the oscillation of the perturb and observe method at the steady state near the maximum power point, which leads to a certain error and combined with the no fluctuation of fuzzy control law in the maximum power point, which has a good dynamic and steady-state performance characteristics, the fuzzy control based on P&O was proposed to achieve maximum power tracking in this paper and it is realized on the Boost circuit. The simulation results showed that the fuzzy control based on the perturb and observe method can quickly and accurately track the maximum power point, avoiding the oscillation of the maximum power point and improving the system stability and efficiency of energy conversion. Source

Xu Y.,North China Electrical Power University | Lan Q.,North China Electrical Power University | Kong X.,Jinshan Power Supply Company | Hong W.,North China Electrical Power University
Diangong Jishu Xuebao/Transactions of China Electrotechnical Society

In order to assess the voltage sag, analyze its impact on sensitive equipment, and develop effective mitigation measures, the full understanding of the voltage sag characteristics is necessary. However, less research work has been focused on the voltage sag characteristics, and its range and distribution are not well understood currently. In this paper, four problems, i. e. statistical analysis of characteristics, classification study, propagation calculations, and sags calculations on the load side, are researched, which aim to lay the foundation for sags assessment and treatment of the gird and sensitive equipment. Firstly, the ranges and distributions of four characteristics, including magnitude, duration, point on wave of initiation, and phase shift, are presented based on the analysis of massive voltage sag events and waveforms recorded by multiple power quality monitoring systems in China. Secondly, a more generalized voltage sags classification method considering the phase shift is proposed on the basis of original methods. Then the transformers' effects on the phase shift of various voltage sag types are studied. Finally, to simplify the sags calculation of the load and associated nodes, the superposition calculation methods concerning transforms and lines are proposed, which can treat multiple transforms and load connections and thus improve the research on the propagation characteristics of voltage sags. © 2016, The editorial office of Transaction of China Electrotechnical Society. All right reserved. Source

Zhao D.-D.,China Electric Power Research Institute | Han Z.,Jinshan Power Supply Company | Guo J.,Xian Jiaotong University
Gaoya Dianqi/High Voltage Apparatus

With increasing requirement for electricity, the voltage level and transmission capacity of power transmission lines get larger, which results in more and more electric loss due to inductive current in ground wire and operation cost. In this paper, the amplitudes of inductive voltage and current, the electric loss of overhead ground wire, and the amplitude of overvoltage on transmission line are calculated for different grounding modes. The results show that the amplitudes of inductive voltage and current as well as the electric loss of overhead ground wire get the minimums when OPGW takes segment insulation with one point earthing, while the zero-sequence impedance and the amplitude of overvoltage become higher in this grounding mode. Both grounding modes of overall insulation and overall insulation with two ends earthing for OPGW are not recommended. Source

Qiu C.,Qingpu Power Supply Company | Li J.,Jinshan Power Supply Company | Pan G.,Jinshan Power Supply Company
China International Conference on Electricity Distribution, CICED

In light of an 110KV indoor GIS substation of certain power supply company, two kinds of three-dimensional solid model (straight Tube-Shaped and T-Shaped) of the GIS bus-bar cylinder are established. The magnetic field, eddy current field of the established GIS bus-bar model is calculated under different conditions such as symmetry currents, asymmetric currents based on ANSYS/EMAG. By the simulation, we get the magnetic intensity distribution of the GIS bus-bar, the eddy current distribution of the GIS bus tube distribution and the power losses on different situations. According to the calculation result of the power losses, the SF6 fluid, temperature field of the GIS bus-bar is analyzed and calculated by the FLUID142 element of ANSYS. In order to verify the accuracy of the calculation results, the simulation of the GIS tube temperature is compared with the actual temperature measured during the GIS operation under different situations according the simulation. The simulation results are proved to have a good agreement with the measured data © 2012 IEEE. Source

Yang J.,Jinshan Power Supply Company | Lu H.,Jinshan Power Supply Company | Shi F.,Jinshan Power Supply Company
Advanced Materials Research

Pumped storage is the largest-capacity form of grid energy storage available. A multi-period oligopolistic model for analyzing the bidding strategies of pumped storage GenCo (PSG) is proposed in this paper. In the pumping periods, the pumped storage unit (PSU) is simulated as a special load. While in generating periods, PSU is treated as a normal generator. In this model, all GenCos are assumed to exercise Cournot strategies to maximize their own profits. The resulting equilibrium formulation is established in terms of a mixed linear complementarity problem. The purpose of this paper is to provide an efficient simulation tool for the PSG to determine its bidding strategy in an oligopolistic environment. The proposed model can also be used to study various factors that may impact PSG's profit. Results of a six-bus test system are analyzed to illustrate the characteristics of the proposed model. © (2013) Trans Tech Publications, Switzerland. Source

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