High accuracy partial discharge location in power module using multiple loop sensors

Existence of partial discharge (PD) is one of the key issues in high-voltage power module. Thus, identifying a PD location in a power module leads to a higher voltage operation of a power module. An attempt is made to identify PD location in an IGBT power module by measuring electromagnetic wave (EMW) detected by multiple loop sensors. In this paper, a novel technique for identification of PD source is proposed by utilizing the polarity reversal of the first rising part of detected EMW signals and Time of Flight (TOF) method with four loop sensors. As the result, it is found that the method utilizing the polarity reversal of EM waveform allows PD location with accuracy of 1 mm. And it is found that TOF method with sampling frequency of 80 GS/s allows PD location with accuracy of 1 mm.