基于实际控保录波的HVDC送端区内阀短路故障定位

Valve Short-circuit Fault Location in HVDC Rectifier Based on Actual Control and Protection Recording Wave

为高效、快速识别高压直流输电系统整流站区内4种典型阀短路故障,提出融合控保录波数据的阀短路故障定位方法。首先,基于Y桥和D桥阀短路保护动作,识别12脉动换流器出线短路;然后,根据阀短路保护动作后执行的控制逻辑引起的各桥故障电流特征差异,在考虑控制系统对故障特征影响的基础上,设计基于不同阀导通状态时各桥三相电流标幺化的阈值分类判据,以区分区内交流侧相间短路和各桥桥臂短路及换流器6脉动换流器出线短路。最后,基于RTDS与实际控保系统的闭环仿真平台,验证了本文所提阀短路故障定位方法的有效性。

To efficiently and quickly identify four typical valve short-circuit faults in the rectifier station area of a high voltage direct current(HVDC)transmission system,a valve short-circuit fault location method is proposed,which integrates the control and protection recording wave data. Based on the valve short-circuit protection actions of the Y-bridge and D-bridge,the short-circuit at the outlet of the 12-pulse converter is identified. According to the difference in fault current characteristics of each bridge caused by the control logic executed after the valve short-circuit protection action and based on the influence of the control system on fault characteristics,a threshold classification criterion based on the per-unitization of the three-phase currents of each bridge in different valve conduction states is designed,thus distinguishing the inter-phase short-circuit on the AC side,the short-circuit of each bridge arm and the short-circuit at the outlet of the 6-pulse converter. Finally,based on a closed-loop simulation platform of RTDS and the actual control and protection system,the effectiveness of the proposed valve short-circuit fault location method is verified.