三广直流鹅城换流站换相失败原因分析

Analysis of commutation failure reason in Three Gorges-Guangdong HVDC system Echeng station

在简要介绍换相失败基本原理的基础上,根据现场的暂态故障录波图,对三广直流鹅城换流站发生换相失败的原因进行了详细分析。比较了在ABB直流控制保护系统中采用预测型关断角的前提下,由于交流系统故障和丢失脉冲所引起换相失败的不同后果。最后提出了一种根据比较故障录波中关断角减小时刻和阀侧三相电流同时过零点时刻先后次序,快速定位换相失败原因的方法,对直流系统的现场运行具有一定的帮助和指导意义。

On the basis of the introduction of commutation failure principle, analysis of commutation failure in Three Gorges-Guangdong HVDC system Echeng station is made according to the transient fault record. This paper compares the commutation failure different results caused by AC system fault and missing pulse in the condition of prediction extinguish angle in ABB HVDC control and protection system. Finally, it puts forward a method of distinguishing the commutation failure reason by comparing the time of reducing extinguish angle and the time of 3-phase current of valve side crossing zero at the same time, which is helpful to the operator in HVDC system station.