发电机在运行中，发生单相接地是常见的故障，其危害性在于故障点出现电弧接地时会进一步扩大定子绕组绝缘损害范围，甚至烧损铁芯，如不及时发现并快速切除故障，将发展成为相间或匝间短路。

In the operation of generators, single-phase grounding is a common fault. Its harmfulness lies in that when arc grounding occurs at fault points, the damage scope of stator winding insulation will be further expanded, and even the iron core will be burned. If faults are not detected in time and quickly removed, it will develop into inter-phase or inter-turn short circuit.

基于上述原因，国际广泛采用发电机中性点高阻接地，以限制接地电流和阻止各种过电压的危害。

For these reasons, high resistance grounding of generator neutral point is widely used in the world to limit the grounding current and prevent the harm of various overvoltages.