Taking 10 kV distribution networks with capacitive current lower than 10 A as an example,we analyzed the advantages of the high-resistance grounding mode and the selection of value of the resistance,and calculated the suppression of overvoltage and detection of faulty feeder under that grounding mode.

This paper analyzes the classification and advantages of resistance grounding modes.

Aiming at high-resistance grounding faults,the operating characteristics of phase current differential protection and zero-sequence current differential protection are analyzed,and a conclusion is obtained that when high-resistance grounding,zero-sequence current differential protection is more sensitive than phase current differential protection.

Based on probability analysis,a new method of fault detection and location in distribution network grounding with high resistance is proposed in this paper.

With comparing different methods of grounding and considering different factors, high resistance grounding was selected.

The design features of service power system in Huizhou Gas Turbine Power Plant are as follows:to adopt two-winding transformer for high voltage service power,the bus section for medium voltage service power is designed as one section;to adopt high resistance grounding for the neutral point of high voltage service power .

Taking the faults of high resistance grounding before and after the capacity expansion of Datong-Qinhuangdao Line,and starting from the introduction of current increment protection principles,this paper analyzes the problem of high resistance grounding in tractive power supply system,and probes into the significance of current increment protection.