1000kV特高压站电容器组桥差不平衡保护的应用

Application of Unbalance Protection of Capacitor Bank in 1 000 kV Ultra-high Voltage Station

从电容器内部结构出发简单介绍了电容器内熔丝保护原理,电容器内部元件如果发生绝缘击穿,与之串联的内熔丝熔断,电容器组电容会发生相应变化,最终导致不平衡电流的变化。文章对两种典型的电容器组双桥差不平衡电流保护进行了计算和分析,推出简易的计算公式,并通过电容器组的实际运行数据对其应用加以验证。

In this paper, the principle of the protection of the capacitor with internal fuse is intro- duced briefly according to the internal structure of the capacitor, if the internal components of the capacitor breakdown, the series internal fuse in fuse, the capacitance wiU change accordingly, and will lead to the changes of the unbalanced current ultimately. In this paper, two kinds of typical pro- tection on double differential current bridges of large capacity capacitor bank are calculated and ana- lyzed, a simple formula is derived, and according to actual operating data, the practical applications are verified.