Modern technologies in optical partial discharge detection

The knowledge of the condition of electrical equipment of power systems is a fundamental part for the reliability of energy systems. For the evaluation of the insulation condition of high voltage power equipment the partial discharge detection is one standard instrument. As diagnostic tool the partial discharge measurement is used in many applications, for testing and comparing different types of insulating materials and also to check complete devices or systems. Improvements, new developments as well as lower costs of sensors, processing and analysing units are some reasons for the increasing of PD diagnostic systems. This paper presents an overview about technologies for the optical partial discharge detection. Based on the emitted light produced by ionization, excitation and recombination processes during the discharge different parameters must be considered and diverse detection techniques are discussed. Additional some fundamental investigations of the discharge properties and their temporal behaviour in different insulation mediums were examined with a developed optical PD-detection system.