根据高岭背靠背直流工程调试阶段出现的阀脉冲丢失故障情况，分析阀故障对于直流运行的影响以及相关保护配合关系，论证了阀脉冲丢失的故障类型，利用PSCAD/EMTDC数字仿真验证故障过程分析的正确性，研究结果可为直流换流站现场运行维护提供参考。

According to the valve pulse loss phenomenon during debugging stage of Gaoling back-to-back HVDC system, the influence of valve pulse loss on the HVDC system operation and the protection coordination were investigated. The fault type of pulse loss has been dissertated, and the simulation results of PSCAD/EMTDC were demonstrated to verify the validity of the fault analysis. The research results provide theoretical guidance and help for the operation and maintenance of HVDC converter station on site.