Abstract:This paper presents a dc capacitor voltage distributed control system (DCS) for cascaded H-Bridge (CHB) multilevel static synchronous compensators (STATCOM). The master cell dc voltage is controlled by central controller, and the slave cell dc voltages are controlled by individual cell controllers. Only one dc voltage needs to be sent to the central controller, and the signals received by all cell are same. This makes the communication system very simple. Meanwhile, when the cell number changes, the central control algorithm is almost unchangeable. But the sum of all dc voltage control variables is not zero, and this will degrade the performance of DCS. Under the master cell control, the quantitative relation between dc voltage control variable and power loss difference is deduced, and decoupling between different cells is verified. The correctness of this quantitative relation is showed by simulation, and the validity of DCS is verified by the experimental results.
宫力, 康勇, 陈晶晶, 黄云辉, 戴珂. 链式STATCOM直流电容电压分布式控制[J]. 电工技术学报, 2011, 26(10): 217-223.
Gong Li, Kang Yong, Chen Jingjing, Huang Yunhui, Dai Ke. DC Capacitor Voltage Distributed Control System for Cascaded Multilevel STATCOM. Transactions of China Electrotechnical Society, 2011, 26(10): 217-223.
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