Power electronics have been playing a big role in many fields of our daily lives. However, as has been well known, at least among high voltage electrical insulation engineers for these two decades, this situation brings about a drastic increase in the risk of partial discharges (PDs). That is, compared with ac voltages with sinusoidal wave shapes at frequencies of 50 or 60 Hz, voltages fed from or induced by power electronic circuits or devices such as converters and inverters contain much shorter fronts and tails in their waveforms. In addition, such devices generate surge voltages with higher amplitudes. Therefore, as power electronic devices are used more and more widely, PDs could be induced much more frequently. This, in turn, increases the importance of monitoring the occurrence of PDs in electric power apparatus such as transformers and rotating machines like motors and generators. However, it is in general difficult for conventional PD testers to monitor PDs generated by such converter-fed voltages. With this background, ECG Kokusai Co., Ltd., Tokyo, has developed a variety of PD testers. In this short article, two of them are briefly introduced.

中文翻译：

---

日本新闻

电力电子在我们日常生活的许多领域都发挥着重要作用。但是，众所周知，至少在这二十年的高压电气绝缘工程师中，这种情况导致局部放电（PDs）的风险急剧增加。也就是说，与频率为50或60 Hz的具有正弦波形的交流电压相比，从功率电子电路或设备（例如转换器和逆变器）馈送或感应的电压在其波形中的正反面要短得多。另外，这样的设备产生具有更高幅度的浪涌电压。因此，随着电力电子设备的使用越来越广泛，PD的产生可能会更加频繁。反过来，增加了监视电力设备（如变压器）和旋转电机（如电动机和发电机）中PD发生的重要性。但是，常规的PD测试仪通常难以监视由这种转换器馈电电压产生的PD。在这种背景下，东京的ECG Kokusai Co.，Ltd.开发了各种PD测试仪。在这篇简短的文章中，简要介绍了其中两个。