With the widespread application of power electronic switching technology, power equipment is facing new electrical stresses brought about by multilevel staircase voltages during testing and operation. Therefore, the partial discharge (PD) behavior of five typical defects in power equipment under the staircase waveform needs to be investigated. This article mainly analyses the phase-resolved PD (PRPD) pattern and pulse repetition rate (PRR) of five typical defects under sinusoidal voltage and multilevel staircase voltage with different number of levels. Also, the PD behavior under staircase voltage with different step responses are investigated. By analyzing the reasons behind the PD behavior between different cases, the PD characteristics and the transformation of PRPD patterns under different staircase voltages are obtained. Moreover, this research finds that the sensitivity of different defects to the staircase voltage is different. These results provide experimental and theoretical support for the testing and diagnosis of PD under new electrical stress present in the future flexible electric grid.

中文翻译：

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多级阶梯电压下电力设备典型缺陷的局部放电行为


随着电力电子开关技术的广泛应用，电力设备在测试和运行过程中面临着多级阶梯电压带来的新的电应力。因此，需要研究阶梯波形下电力设备五种典型缺陷的局部放电（PD）行为。本文主要分析了正弦电压和不同级数的多级阶梯电压下五种典型缺陷的相位分辨局部放电（PRPD）图案和脉冲重复率（PRR）。此外，还研究了具有不同阶跃响应的阶梯电压下的局部放电行为。通过分析不同情况下PD行为背后的原因，获得了不同阶梯电压下的PD特性和PRPD模式的转变。而且，本研究发现不同缺陷对阶梯电压的敏感性不同。这些结果为未来柔性电网新电应力下局部放电的测试和诊断提供了实验和理论支持。