高压断路器T100a开断试验最后电流半波参数及TRV参数计算

Calculation of Last Current Loop Parameters and TRV Parameters in T100a Breaking Test of High Voltage Circuit-breakers

非对称短路故障开断试验T100a是高压交流断路器型式试验的重要试验项目,中性点非有效接地系统中的断路器首开极系数为1.5,暂态恢复电压(TRV)具有两参数或四参数特征。通过建立T100a开断试验短路电流和电压表达式,分析与计算了中性点非有效接地系统中首开大半波和延长大半波情况下的三相开断过程,进一步计算了两种情况下首开极和晚开两极的最后电流半波参数及TRV参数。并分别以额定电压40.5 kV和额定电压126 kV断路器进行T100a开断试验为例计算了最后电流半波参数和TRV参数,计算结果为断路器的开断试验提供考核依据。

Asymmetric short-circuit fault breaking test T100a is an important test item of High-voltage AC Circuit-breakers.In non-effectively earthed neutral system the first pole to clear factor is 1.5 and the transient recovery voltage(TRV)has two or four parameters.By establishing the expression of short-circuit current and voltage in T100a breaking test,the last current loop parameters and TRV parameters are analyzed and calculated in major loop and extended major loop.Finally,the last current loop parameters and TRV parameters are calculated by taking T100a interruption test of rated voltage 40.5 kV and rated voltage 126 kV Circuit-breakers as examples,which provide an assessment basis for the breaking test of circuit breakers.