A NEW PROTECTIVE METHOD FOR GRID CONNECTED DISPERSED PV SYSTEMS TO DETECT SHORT CIRCUIT FAULT IN DISTRIBUTION LINE

摘要

A new protective measure installed in the grid connected dispersed PV system for detecting short circuit fault with high-resistance in a high-voltage distribution line was designed. Relationship between voltage absolute value change and voltage phase change of the distribution line is monitored in the measure for achieving not only enhancement of detective performance but also prevention of misdetection in normal operation of the grid. It was clear from simulation results that the number of PV systems detecting the fault increased about 2 times as much as the existing method and the reduction of fault current at utility substation, which causes dangerous inability of utility's protection, could be prevented effectively. [References: 4]