The Control Technology of Three-Phase Unbalance Load in Low Voltage Distribution Networks Based on Coordinated Controlled SVGs
Deng Huihua1, Li Guoliang1, Zhou Xiaoming1, Li Hanrong1, Wang Hao2
1. Huizhou Power Supply Bureau of Guangdong Power Grid Co., Ltd Huizhou 516001 China; 2. Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China
Abstract：Concentralized static var generator (SVG) compensation system has single compen -sation effect and distributed SVG compensation system without communication function can not distribute SVG's compensation capacities intelligently. Aiming at these problems, a compensation system based on SVGs' coordinated control strategy was proposed for three-phase unbalance load in low voltage distribution network. Communication bus and coordinated control strategy are introduced in the proposed system. After compensating the downstream unbalance current, the residual capacity of the downstream SVG is used to compensate the upstream SVGs in sequence. The low voltage problem of each node is further reduced by the reverse power flows from the downstream SVG to the upstream SVG. And then SVG's capacity in the proposed compensation system can be fully used. Meanwhile, the problems of the distribution transformer's unbalance current and the node's low voltage are synthetically solved. Simulations for actual effect evaluation of the proposed compensation system were done in Matlab/Simulink. Validity of the proposed system is confirmed by the simulation. In four different load cases, four different compensation systems were applied in low voltage distribution station, respectively. Unbalance currents of distribution transformer secondary and node voltage drops in these cases were compared. Comparison results show that proposed compensation system has the best compensation effect.
邓惠华, 李国良, 周晓明, 李汉荣, 王浩. 基于协调控制SVG的低压配网三相负荷不平衡治理技术[J]. 电工技术学报, 2017, 32(增刊1): 75-83.
Deng Huihua, Li Guoliang, Zhou Xiaoming, Li Hanrong, Wang Hao. The Control Technology of Three-Phase Unbalance Load in Low Voltage Distribution Networks Based on Coordinated Controlled SVGs. Transactions of China Electrotechnical Society, 2017, 32(增刊1): 75-83.
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2017, Vol. 32 
