Research and Application of a Line Fault Location System in Chongqing

Chongqing is located in southwest China, where the landform mainly consists of hills and mountains and there are broad sloping areas. In order to rapidly locate and isolate faults and facilitate inspection, a line fault location system suitable for Chongqing's mountainous terrain was designed in this paper where the structure of the line fault location system was proposed, and the key technologies related to the core components of the system such as fault indicators and signal generators were described in details. This system uses fault indicators designed based on the signal injection method to realize fault line selection and fault section location for single-phase ground faults in the 10kV neutral ungrounded system. In this way, the misjudgments on load fluctuations and on-off inrushes by the fault indicator can be avoided effectively. The experimental results and practical application show that this line fault location system is applicable to the mountainous terrain in Chongqing, and it takes less time to find out and handle faults, thereby enhancing distribution automation.