Partial discharge inception voltage (PDIV) at different frequencies is of great interest for PD tests conducted at nonpower frequency. However, in the existing literature, there is no agreement on PDIV characteristics with respect to frequency. There is a lack of comprehensive analysis of frequency-dependent PDIV characteristics either. In this article, the PDIV of a cylindrical void at different frequencies (from 0.5 to 300 Hz) is investigated from the perspective of the first PD time lag. First, an appropriate time interval between consecutive measurements is experimentally determined. Then, PDIV measurements at different frequencies are conducted by increasing voltage at a fixed ramp rate. Furthermore, the PDIVs defined by peak voltage and instantaneous voltage are compared. After that, a bipolar square wave is applied to measure the first PD time lag. Finally, based on the first PD time-lag distribution with respect to voltage at different frequencies, the cumulative probability of the first PD under sinusoidal voltage is computed and analyzed. The results suggest that the first PD time lag has a significant influence on the measured PDIV at frequencies above 10 Hz. This is because the mean time lag is nearly half the time period of half voltage cycle at low voltages. Thus, high voltages (HVs) are needed to obtain a high probability of the first PD, i.e., a large measured PDIV.

中文翻译：

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从首次局部放电时滞角度观察不同频率纸板封闭空隙局部放电起始电压的实验研究


不同频率下的局部放电起始电压 (PDIV) 对于在非工频下进行的局部放电测试非常重要。然而，在现有文献中，对于频率方面的 PDIV 特性尚未达成一致。也缺乏对频率相关的 PDIV 特性的全面分析。本文从第一 PD 时滞的角度研究了不同频率（0.5 至 300 Hz）下圆柱形空隙的 PDIV。首先，通过实验确定连续测量之间的适当时间间隔。然后，通过以固定斜率增加电压来进行不同频率下的 PDIV 测量。此外，还比较了由峰值电压和瞬时电压定义的PDIV。之后，应用双极方波来测量第一个 PD 时滞。最后，根据不同频率下电压的首次局部放电时滞分布，计算分析了正弦电压下首次局部放电的累积概率。结果表明，第一 PD 时滞对频率高于 10 Hz 时测量的 PDIV 有显着影响。这是因为平均时滞几乎是低电压下半电压周期时间周期的一半。因此，需要高电压（HV）来获得第一PD的高概率，即大的测量的PDIV。