PD Apparent Charge Estimation and Calibration: a Critical Review

This paper focuses on the limits of partial discharge apparent charge estimation and calibration using an unified approach. The fundamental problems that prevent accurate apparent charge estimates (resonances, attenuation and partial discharge pulse splitting) are tackled through this approach, highlighting the physical limitations that prevent partial discharge charge to be measured properly. The feasibility of calibration of Ultra-Wide Bandwidth measurement systems, something that is not treated in the IEC 60270 standard, is also discussed.