Estimation Method for Actual Partial Discharge Quantity in HVDC GIL Based on Second Integration of UHF Signals Over Time

The assessment of partial discharge within GIS includes the estimation of discharge quantity, and the currently recognized method is the pulse current method, which is supported by both national and international standards. However, this method has limitations: it can only detect apparent discharge quantity, its detection sensitivity is highly correlated with the test object, and the calibration of apparent discharge quantity requires offline testing with specific experimental conditions. On the other hand, using UHF signals for discharge quantity calibration offers advantages such as easy detection and feasibility for online monitoring. This study explores the relationship between UHF signals and discharge quantity, deriving the correlation between partial discharge quantity and the radiated electromagnetic field. It further investigates the connection between UHF signals and discharge quantity, ultimately proposing a method for estimating the maximum actual discharge quantity based on UHF signals.