Partial discharge fault location and diagnosis on HV power cables

Risk assessment with a large population of service-aged distribution class cables demands field-applicable partial discharge measurement techniques. Recent experience with lightweight portable instruments applied with resonant test sets as well as with O.1 Hz high voltage sources is presented. Application of correlation functions to compensate the influence of high frequency properties of power cables, such as attenuation or dispersion, are used to improve location accuracy. Additionally, characteristics of phase-resolved partial discharge patterns to assess cause and potential risk of the discharge activity are discussed, Furthermore, methods and application of hand-held instruments to fine-locate the site of discharge activity are presented.