基于预充电的电容器组投切控制策略

为了减小配电网中无功补偿并联电容器组投切时所引起的涌流和过电压,对电容器组的投切过程及其自适应控制进行了研究,提出一种采用普通接触器的投切策略.该策略利用电网特性,通过二极管支路预先使三相电容器中的两相充电,使得一个周期内三相电压波形存在唯一一个同时过零点.在该过零点投入电容器组,能有效降低合闸涌流及过电压.仿真表明,采用该策略投切电容器,电容器合闸涌流被限制在2.5 p.u.以下,电压波形畸变很小.通过添加二极管支路预充电能有效地改善电容器组投切时的暂态性能,从而延长电容器的使用寿命.

Shunt capacitor bank switching strategy based on precharge circuit

In order to reduce the inrush current and overvoltage caused by switching transients of var compensating shunt capacitor bank in distribution network,the switching process of capacitor bank and its adaptive control are researched,based on which the switching strategy for common contactor is proposed. It precharges the capacitors of any two phases through the added diode branches to produce a synchronous zero voltage point for all shunt capacitors of three phases based on the feature of power grid. The shunt...