Partial Discharge alert system in medium voltage switchgear

Abstract

Partial discharge (PD) is a well-known indicator of insulation problems in high voltage equipment. We report on experience collected during the development of a new online PD detection and alert system for air insulated switchgear (AIS) installed base. The approach taken to integrate the sensor with minimal retrofit effort and operational disruption is described. Results from a test setup including a line-up of panels and different reference PD sources in comparison to a commercial PD system are presented. The effect of cables connected to the switchgear is investigated by testing the system including additional capacitive load and using a simulation for a typical geometry. We also address the question regarding the design of an alert system to be used in connection with the continuous data acquisition.