Method and system for adaptive single-phase reclosing of wind farm ac transmission lines

Abstract

This invention relates to a method and system for adaptive reclosing of single-phase AC transmission lines in wind power systems. The invention utilizes single-ended electrical quantity to determine the type of fault. After a fault occurs, a signal acquisition device is used to sample the voltage of the fault phase. The obtained voltage is subjected to short-time Fourier transform to extract the amplitude of the fundamental frequency voltage component, and then processed with differential amplification to construct a fault nature identification criterion. Combined with a sliding time window for fault identification, if it is identified as a permanent fault, the reclosing device is locked out; if it is identified as a transient fault, the fault disappearance time is calculated to determine the reclosing time and output the closing signal. This invention is designed for adaptive reclosing after a circuit breaker trips in wind power AC transmission lines.