Partial Discharge Current Measurements With Small Discharge Gaps Over Polyimide Film
Partial Discharge Current Measurements With Small Discharge Gaps Over Polyimide Film
复制标题
聚酰亚胺薄膜上小放电间隙的局部放电电流测量
DOI：
10.1109/tdei.2022.3226133
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发表时间：
2023
影响因子：
3.1
通讯作者：
Uehara Hiroaki
中科院分区：
文献类型：
--
作者：
Okamoto Tatsuki;Uehara Hiroaki
小间隙局部放电特性对确定电力设备中聚合物的局部放电电阻非常重要。特别是，用于小型动力设备的聚合物的PD特性，例如电动汽车的功率模块而不是汽油发动机，已经变得非常重要。在高分子绝缘材料中，我们选择广泛用于电路安装的聚酰亚胺（PI）作为我们的目标绝缘膜样品。为了深入了解PD机制，我们测量的是纳秒级PD脉冲电流波形，而不是PD研究的主流——特征。虽然有很多研究使用了从PD脉冲电流中集成的PD电荷量，但很少有研究测量高速纳秒级PD脉冲电流本身，因为它容易被噪声所掩盖。在本研究中，我们测量了交流峰值电压为2000 V及以上的50-1000 Hz下的PD波形，以阐明波形以了解低压PD特性。电极系统是一种简单的针平面电极，放电间隙小，为0、75和。从高压电极到PI薄膜的电流方向被确定为“正电流”。我们发现，在几乎所有施加的电压频率下，正电流的大小几乎是负电流的两倍，而负电流的持续时间几乎是正电流的一半。正脉冲和负脉冲的波形差表示电子和离子的电荷源差。本研究有助于对PD机制的理解。
Partial discharge (PD) characteristics obtained with small gaps are very important to determine the PD resistance of polymers in power equipment. Particularly, PD characteristics of polymers used in small-sized power equipment, such as the power module of an electric vehicle instead of a gasoline engine, have become very important. Among polymer insulating materials, polyimide (PI), which is widely used for circuit mounting, is selected as our target insulating film sample. To understand PD mechanisms in depth, we measure nanosecond PD pulse current waveforms instead of the--characteristics, which have been the mainstream of PD studies. Although numerous studies have used the amount of PD charge integrated from the PD pulse current, few studies have measured the high-speed nanosecond PD pulse current itself, which is easily buried in noise. In this study, we measure PD waveforms under an ac peak voltage of 2000 V and more at 50–1000 Hz to clarify the waveforms to understand low-voltage PD characteristics. The electrode system is a simple needle-plane electrode with small discharge gaps of 0, 75, and. The current direction from the high-voltage electrode to the PI film is determined as a “positive current.” We found that the positive current magnitude is almost twice the negative one, whereas the negative current forms have almost half the duration time of that of the positive ones at almost all applied voltage frequencies. The waveform difference between positive and negative pulse indicates charge origin difference as electrons and ions. This study contributes to the understanding of PD mechanisms.