The method of short circuit fault identification and location in high-voltage transmission line

That the phenomena of transmission line fault takes place occasionally in our country has a severe impact on power system stability. It has great significance for reliable power supply to identify short circuit fault and cut it quickly. A new method of fault identification and location is proposed in the paper. On the analysis of fault disturbance characteristic, the method is based on cubic interpolating polynomial and extracts transient DC disturbance from fault signal. Then the polarity of the current disturbance is used to identify fault line and the position of the short circuit point is located by the defined delay function. Thus the fault location error of line parameters is avoided and the location result is not influenced by system operation mode and transition resistance. The accuracy and reliability of the method are proved by the simulating model with two generators and an infinite system. The result of simulating test shows that the location of short circuit point can be determined very quickly. And also, the number of measuring units is so little that huge investment can be reduced.