Zou L.,Shandong University |
Liu T.,Shandong University |
Zhao T.,Shandong Provincial Key Laboratory of UHV Power Transmission and Transformation Technology and Gas Discharge |
Zhang L.,Shandong Provincial Key Laboratory of UHV Power Transmission and Transformation Technology and Gas Discharge |
Li Q.,North China Electrical Power University
Dianwang Jishu/Power System Technology | Year: 2014
To implement fast and accurate diagnosis of commutation failure to take effective control measures and mitigate the impact of commutation failure on HVDC transmission system, through analyzing the mechanism and the process of commutation failure it is considered that such phenomena as the valve voltage continuing to be zero, the valve current continuing to be nonzero and keeping a higher amplitude can be regarded as essential characteristics of commutation failure, and accordingly a valve voltage or valve current based method to diagnose commutation failure is proposed. When the duration of the valve voltage continuing to be zero or the valve current continuing to be nonzero is longer than one power frequency period, it can be judged that the commutation failure occurs. Both results of theoretical analysis and simulation prove that using the proposed method, not only the commutation failure can be effectively diagnosed, but also the converter valve, where the commutation failure occurs, can be intuitively displayed, and its principle is simple and there is not the blind area during the diagnosis. ©, 2014, Power System Technology Press. All right reserved.