Study On Fault Location Of Parallel Transmission Line Based On Six Sequence Networ

The double transmission line on the same tower requires narrow corridors, the transmission ability is strong, and investment is saved. Thereby, it is used by line system more and more. Due to the effect of the line faults for the stability and reliability of power system is not neglected, the fault location had become a problem that got more attention from the department of power network management and experts.The structure of the double line on the same tower is complex, and frequently subjects a variety of technical problems in the view of protection engineering. These problems are mainly due to the mutual coupling between lines and the multiple branch of teed connection, which requires choosing faulted branch before fault location.A new accurate fault location algorithm for parallel transmission line on the same tower is introduced in this paper. Depending on six-sequence fault component method, the coupled transmission equations are transformed into decoupled ones. Based on the detailed analysis of peculiar characteristic of parallel transmission line, the inverted positive sequence component measurement, which is used to implement fault location for parallel line.The influence of filtering on the location accuracy, improved the difference FFT algorithm with the idea of setting compensation angle, difference Fourier filtering algorithm, the simulation indicated that the improved filtering algorithm with less calculation, high precision. And it is conducive to fault location.Abundant results of PSCAD simulation demonstrate that the new method can give accurate fault location and be implemented easily. The location accuracy is not influenced by factors such as fault resistance, fault type and generation mode.