Study on Voltage Control Method of AC Filter Banks in HVDC Project

Abstract

The single-phase voltage of the AC bus in converter station is applied to control AC filter voltage in Xiluodu HVDC project, the accuracy and reliability are not as good as the three-phase voltage of the multiple-way AC filter banks. This paper presents a new method for controlling AC filter voltage, abnormal bus voltage of AC filter banks are divided into three cases: bus bar not charged, bus voltage over-limit and bus voltage deviation. According to the anomaly type and selection priority of AC filter voltage, a more reasonable AC filter voltage is chose as the output value of AC filter voltage controller. Simulation results show that the application of a new AC filter voltage control method can correctly select the AC filter bus voltage, and avoid the abnormal measurement of AC filter banks voltage which may lead to the unusual switching on/off of AC filters. 