新型正弦脉宽调制控制电压源型动态静止无功补偿器

提出了一种适用于低压配电系统的新型动态无功补偿电路拓扑。主电路采用三相四桥臂逆变器结构，可以对负荷不平衡进行有效补偿。逆变器控制采用正弦脉宽调制(sinusoidal pulse width modulation，SPWM)控制，保证电压电流失真度低，并通过调节逆变器的输出电压从而动态调节静态无功补偿器(static var compensator，SVC)补偿无功功率，最终实现系统无功补偿为零的目的。通过与固定补偿电容器相结合，它能以较小的逆变器容量来补偿动态无功，提高系统的功率因数和电压稳定性。利用PSCAD/EMTDC平台对该系统进行了仿真研究。仿真结果验证了控制策略的可行性和有效性。

Novel Sinusoidal Pulse Width Modulation Controlled Voltage Source Converter Dynamic Static Var Compensator

A novel dynamic reactive power compensation circuit topology suitable for low voltage distribution system was proposed. The efficient compensation of unbalanced load could be realized by the structure of three-phase four-leg inverter circuit. The sinusoidal pulse width modulation (SPWM) control of inverter could ensure the low distortion of voltage and current. Besides, by the regulation of the inverter’s output voltage, the compensation reactive power could be dynamically regulated and the aim of system’s zero reactive power compensation could be realized. Combined with fixed capacitor compensator, small capacity of inverter is required to compensate dynamic reactive power. The novel dynamic static var compensator (SVC) could improve the system’s power factor and voltage stability. Finally, simulations are carried on the platform of PSCAD/EMTDC. The results show that the proposed control strategy is feasible and efficient.