A validated accurate fault location approach by applying noise cancellation technique

Generally, fault location in underground transmission cable system is very difficult because of many noises. Therefore, a method to remove the noise in power cable systems is proposed by applying noise cancellation technique based on the correlation of multiple scales of the transients using wavelet analysis. After the noise cancellation, the transient signals reflected from fault point and other end of cable can be used to locate the fault using single-ended approach when the single line-to-ground fault occurs in underground transmission cables. This paper proposes a fault location algorithm using noise cancellation technique in noisy environment. This algorithm is simple and straightforward. The simulation results of 225 fault conditions including different fault resistance, fault location and fault inception angle and real test results prove it can accurately locate the fault in very noisy situations when the single line-to-ground fault occurs in the system.

► This paper describes a full fault location algorithm including the discrimination of fault section between first half section fault and second half section fault and a fault location method according to fault section for locating the fault in noisy environment by applying the noise cancellation technique at each end of the cable sections. The proposed algorithm is evaluated by both the detailed simulations according to various fault resistances, faulty phases, fault inception angle and fault distances and field tests.
► In this paper, full fault location algorithm was validated by simulations based on a real power cable system as well as practical field measurements on test cable. The average error rate of the simulation for 225 fault conditions is just 0.935% and 0.16% in real test. From these results, it proves that the fault can be accurately located in noisy environment in underground transmission cable systems using proposed fault location approach.