直流换相失败期间阀换相过程微观分析方法

Micro-analysis of valve commutation process during DC commutation failure

从电磁暂态微观尺度角度出发研究了换流器换相失败阀换相过程,分别针对短路状态和线电压长时间加压至直流侧状态提出了2种等值电路。基于这2种电路分析直流换相失败过程中的直流电压变化特征。分析结果表明,直流换相失败过程中逆变侧直流电压不仅会降低,甚至会出现反转的情况。在连接有直流实际控制保护装置的RTDS实时仿真平台上进行仿真试验,试验结果验证了提出的换相失败过程等值电路的正确性。

The valve commutation process during the converter commutation failure is studied on the microscale of electromagnetic transient and two equivalent circuits are proposed for the short circuit state and the DC-side state under long-time line-voltage respectively,based on which,the characteristics of DC voltage variation during the HVDC commutation failure are analyzed. Results show the inverter-side DC voltage during the HVDC commutation failure will decrease and even reverse. Simulation is carried out on RTDS real-time simulation platform including actual control and protection devices,which verifies the correctness of the proposed equivalent circuits.