Yixi Chen^1,, Rong Ju¹, Jie Xu¹, Gang Ma¹, Huaiyi Chen¹, Guchao Xu¹

Resonant grounding system has been widely applied in low-voltage power systems all over the world. For the single-phase ground fault feeder-selection of resonant grounding system, the amplitude/phase comparison method of zero-sequence current which is used in traditional fault feeder-selection is not suitable to be used, due to the compensation action of arc suppression coil. In this paper, the electrical quantity changes after the single-phase ground fault of small current grounded system are analyzed firstly, therefore the reason why the amplitude/phase comparison method of zero-sequence current is not suitable to be used in resonant grounding system can be obtained. After that, based on zero-sequence current’s multi-state components (transient component and steady component), a new fault feeder-selection method using double criteria is proposed, which not only can be applied in the single-phase ground fault of resonant grounding system but also has high reliability. At last, simulations based on MATLAB/Simulink are conducted to verify the validity of the method proposed in this paper.

resonant grounding system, fault feeder-selection, single-phase ground fault, multi-state components