Fault location algorithm for double-circuit UHV transmission lines on same tower

Abstract

A fault location method based on the amplitude characteristics of hyperbolic cosine function is presented for the double-circuit UHV transmission lines on same tower. The half-wave Fourier narrow-band filtering algorithm is applied to extract the electrical fundamental components of both ends and the six- sequence component method is then applied to decouple them. A hyperbolic cosine fault locating function is constructed based on the homotopic positive-sequence fundamental components and the reference point producing the maximum amplitude of fault locating function is taken as the fault location. Theoretical analysis and simulative test prove that, immune to the system impedance, fault point transition resistance, line distributed capacitive current and other factors, the method has high fault locating accuracy and quick calculating speed, meeting the requirements of site applications.