Partial Discharge Measurements on Components Energized by Power Electronic Frequency Converters

The voltage source used for testing electrical equipment has to achieve special requirements, which are noted in the international standards. Still today the test voltages for routineand type tests of utilities for the power engineering are generated by motor-generator sets. Attempting to replace the m.-g. sets with static frequency converters, two major problems occur in implementing this technology for testing applications: the insufficient quality of the output voltage and the high background noise for partial discharge (pd) measurements. This paper deals with the reasons for the high interference level and the elimination of disturbing emission.