高压直流晶闸管阀故障电流下反向电压特性的分析

Analysis on Reverse Voltage Characteristics of HVDC Thyristor Valves in the Fault State

为分析高压直流晶闸管阀故障电流下的反向电压特性,采用电路拓扑模型分析法,建立了故障电流下反向分析的数学模型,并建立相应的试验模型对分析方法进行验证。对晶闸管结温、阻尼电阻电容参数、电流变化率和正向电流4个参数的影响进行了分析,并用数学模型进行仿真计算。分析结果表明:晶闸管结温、电流变化率和正向电流均可导致反向恢复电荷的改变,从而对反向恢复电压造成影响;阻尼电阻电容一定时,有唯一阻尼电阻使反向电压最小。结果验证了该仿真分析方法的可行性,且具有较高的精确度。

The reverse voltage characteristic of HVDC thyristor valve on the state of fault current was analyzed. A mathematics model was put forward by using circuit topology analysis, which can be validated by test. The influence of thyristor junction temperature, current rate of change, forward current and damping parameters was studied and simulated by implementing the mathematic model. The results show that thyristor junction temperature, current rate of change and forward current can change and influence the reverse recovery charge and voltage. When the damping capacitance is constant, a unique value of damping resistance can be achieved leading to the minimal reverse recovery voltage. The feasibility of the simulation method is verified by tests and high accuracy is achieved.