Computer aided partial discharge testing of electrical motors and capacitors

The present methods for testing of low voltage equipment, in particular electrical motors and capacitors are discussed. It is demonstrated that those tests realising high voltage overstress of the object tested cannot guarantee reliable performance of solid insulation throughout the equipment life. Partial discharge (PD) measurement as an alternative is a true nondestructive test method providing detailed information about the duality of manufacturing of the equipment tested and the selection of suitable insulation materials. As mentioned, above two different types of test objects have been investigated. The measurements have been performed by means of a computerised partial discharge measuring system with particular software features which simplify its application. Based on experimental results it is demonstrated that PD tests are of great importance for quality assurance of electrical motors and capacitors. Moreover it seems to be possible to predict the quality of the final product by precise PD investigations and measurements of the materials and components used.