基于坐标变换的凸形TRV波形参考线及特征参数计算方法研究

Research on Calculation Method of Convex TRV Waveform Envelope and Characteristic Parameters Based on Coordinate Transformation

高压交流断路器进行短路开断试验,电流开断后断口间将承受标准规定的暂态恢复电压(TRV),标准规定的TRV参数由参考线和预期TRV标准值来表征。提出了一种基于坐标变换的凸形四参数TRV波形参考线及特征参数计算方法,通过对TRV波形数据进行数学变换,由直角坐标系转换到极坐标系下,可以计算得出与TRV波形相切的三条直线,并结合所建立的局部坐标系,应用面积比较法得出与TRV波形相切的第四条直线,四条直线组成凸形TRV的参考线,进一步计算可以得出TRV的特征参数。最后,通过算例说明了应用本计算方法可以准确获得凸形TRV波形的参考线及标准值参数,为高压交流断路器在短路开断试验时TRV参数的读取与评估提供了一种新方法。

During the short-circuit breaking test of high-voltage AC circuit-breakers,the transient recovery voltage(TRV)specified in the standard will be applied between the interrupter after current breaking.The TRV parameters specified in the standard are characterized by the reference line and the expected standard value of TRV.A method of calculating the reference line and characteristic parameters of convex four parameter TRV waveform based on coordinate transfer is proposed.Through the mathematical transfer of TRV waveform data,from rectangular coordinate system to polar coordinate system,three straight lines tangent to TRV waveform can be calculated,and combined with the local coordinate system established,the fourth tangent to TRV waveform can be obtained by area comparison method.Four lines constitute the reference line of convex TRV,and the characteristic parameters of TRV can be obtained by further calculation.Finally,an example is given to show that the reference line and standard value parameters of convex TRV waveform can be obtained accurately by using this calculation method,which provides a new method for reading and evaluating TRV parameters in short-circuit breaking test of high-voltage AC circuit-breakers.