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Cui Q.,Xian Jiaotong University | Wang X.,Xian Jiaotong University | Liu Z.,Hubei Electric Power Company
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2013

It is an ideal way to solve the bottlenecks of power source and grid construction that setting up large-scale battery energy storage systems on the demand sides. According to specific power market rules, a real-time price dynamic game linkage model considering power generation side, supply side, large-scale battery energy storage system and demand response was established. Based on electricity price signal, each participant adjusted their own game strategy until the equilibrium price was solved. The paper set up three cases to simulate the model. The simulation results showed that large-scale battery energy storage systems set up on the demand side could reduce the difference of valley-to-peak load and smooth the curve of real-time electricity price, the mean electricity price of user was reduced and the power generation and transmission cost was decreased, and some profits were shared by battery energy storage systems. At the same time, the utilization rate of generation and transmission equipments increased. © 2013 Chin. Soc. for Elec. Eng.

Xiao D.-B.,Hubei Electric Power Company | Zhang X.,Gansu Lanzhou EHV Power Transmission Company
Gaoya Dianqi/High Voltage Apparatus | Year: 2011

Several different polluted methods to conduct the insulator flashover performance research are recommended by IEC and China, but the differences between the polluted methods have not been pointed out. Based on the composite insulator, the quantitative brushing method, dipping method and spraying method were compared. The results indicate that, according to the AC pollution tests, the voltage achieved by the quantitative brushing method is about 4.02%~7.73% higher than spraying method, and quantitative brushing method is about 7.66%~13.19% higher than dipping method. It is found that the quantitative brushing method and dipping method have each's characteristic and the appropriate polluted methods should be chosen according to the specific circumstances of the test. The spraying method does not apply to the composite insulator.

Shu J.,North China Electrical Power University | Li C.,Langfang Electrical Power Company | Su J.,Hubei Electric Power Company | Dong W.,Langfang Electrical Power Company
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2012

Due to the difficulty for traditional optimization methods to consider complicated contingency scenarios, an optimal reserve dispatch model considering contingency scenarios based on security constrained unit commitment (SCUC) was presented in this paper. Integrated with unit commitment, power dispatch, reserve capacity optimization and the reserve dispatch, the optimization model is to minimize the sum cost of the electricity and reserve while subjected to the security constraints of base case and contingency scenarios. By introducing scenarios classification and the scenarios set, the demand and dispatch of reserves with different response rates were decided by the requirement of different scenarios. This complicated mixed-integer linear programming problem was modeled by the GAMS and solved by the CPLEX. Numerical case studies illustrated the effectiveness of the proposed approach. © 2012 Chin. Soc. for Elec. Eng.

Ruan Y.,Wuhan University | Yuan R.,Wuhan University | Wan L.,Hubei Electric Power Company | Zhao H.,Wuhan Institute of Technology
Diangong Jishu Xuebao/Transactions of China Electrotechnical Society | Year: 2012

Most nonlinear excitation control methods depend on the operating point of power system and can't assure voltage regulation accuracy of synchronous generators. For this reason, a nonlinear robust voltage control strategy is proposed in this paper. For a synchronous generator connected to power network through a transformer, the mathematical model is transformed into a uncertain linear system with the state variables of deviations of generator terminal voltage, rotor speed and generator active power output. And then a nonlinear voltage controller is designed utilizing a linear matrix inequation(LMI) based robust control theory. Compared with the existing controllers, the proposed controller assures voltage regulation accuracy and adapts to system parameters and operating points. And the controller doesn't need to be respectively designed for single-machine-infinite-bus system and multi-machine power system. Besides that, neither rotor angle nor any variable's differentiation or integration needs to be measured for the controller. Detailed tests were conducted by PSCAD/EMTDC for a single-machine-infinite-bus system and WSCC 4-machine power system respectively, and simulation results illustrate good performance of the proposed controller.

Zhang X.,Gansu Electric Power Company | Xiao D.-B.,Hubei Electric Power Company
Gaoya Dianqi/High Voltage Apparatus | Year: 2013

It has direct relation between the pollution flashover voltages of insulators and the wetting condition of pollution layer of insulators. IEC and national standards specified that wetting time of pollution layer should be controlled in a certain range, however, saturation wetting of pollution layer is influenced by pollution grade, steam flow rate, various insulators and wetting time, there is no in-depth study on saturation wetting. By making research on the wetting process of pollution layer of typical suspension insulators, analyzes the relationship between satiation wetting time and pollution grade, steam flow rate, various insulators, and points out functional relation between influencing factors and saturation wetting time, and confirm test condition on the wetting process. These test results are quite important to guide the artificial pollution test.

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