PD analysis of gas insulated medium voltage switchgear during factory assembly and site commissioning

The Partial Discharge (PD) measurement of medium voltage (MV) gas insulated switchgear as a routine test is according to the standard IEC 62271–200 [1] a subject to agreement between manufacturer and user. However, more and more manufacturers of MV gas insulated switchgears are going to introduce this measurement as a factory test for quality assurance to qualify the proper insulation of the switchgear. Furthermore in the last years the user of MV gas insulated switchgears stated more and more the requirement for PD measurements after erection at site. The main reason is, that despite the current situation of high cost pressure the user has to maintain the reliability of the electricity distribution systems. The important role of medium voltage switchgear to guarantee a high service quality especially in HV-substations led to an increased application of gas insulated switchgears in the last 20 years. Due to the hermetical sealed design gas insulated switchgears have a lot of advantages and show a high reliability.