羊湖电厂110kV线路零序功率方向元件带负荷试验

按绝对值比较原理构成的零序功率方向元件，在零序电流方向保护中应用极为广泛。在常规的模拟调试中难以直接模拟出运行状态下接地故障时的零序电流和零序电压，因此要正确判断零序功率方向元件接线的正确与否，应在带负荷状态下，用负荷电流通过人为改变保护用的电流互感器和电压互感器二次回路的接线方式，来达到试验目的。

Tests on the directional elements of zero-sequence power of 110 kV line for Yamzho Yumco Pumped Storage Station under the load condition

The directional element of zero sequence power, as a judgment element, is made in accordance with the absolute value comparison principle and is widely applied in the direction protection of zero sequence current. In the routine simulation tests, it is difficult to simulate directly the zero sequence current and voltage under the operation condition during earthing failure. In order to judge accurately the correctness of the connection of directional elements of zero sequence power, the tests should be made under load condition. In this way, we can use load current to change the protective current transformer and potential transformer to reach the test objective.