A generalized method to improve the location accuracy of the single-ended sampled data and lumped parameter model based fault locators

The necessity for very high accuracy in fault location is generally becoming more and more important. In this paper, a new generalized algorithm which can improve the accuracy of all fault location algorithms based on the lumped parameter model and single-ended data is presented. The measured distance resulting from the lumped parameter model can be converted to the positive sequence measured impedance matching with the model. Then, the relation between real distance and positive sequence measured impedance of fault circuit based on Bergeron model can be derived according to the analysis of solid grounded faults. Then the improved algorithm resulting from the relation of real distance and measured distance can be obtained. Theoretically, the proposed algorithm is independent of shunt distributed capacitance of transmission lines. Besides, the algorithm is based on power–frequency voltages and currents, and hence high sampling rate is unnecessary. Therefore, it can be implemented in the existing protection devices easily. This paper presents the theory of the technique and the results of ATP simulation tests to demonstrate its performance.