Partial Discharge Diagnostics on High- and Extra-High-Voltage Cable Systems in Disturbed Environments – Strategies, Sensor Technologies and Test Methods

Abstract

The continuous increase in the demand for electrical energy and the associated expansion of power networks are driving the need for ever-improving operational reliability, safety, and the diagnostic value of measurement techniques. In polymer-insulated cable systems, partial discharge (PD) measurement has already become an important method for increasing network reliability, particularly as part of commissioning tests. While PD measurements performed in shielded laboratory environments focus on the precise determination of partial discharge levels, measurements carried out in the field-especially on long power cable systems-are faced with the significant challenge of detecting and identifying partial discharges in a disturbed electromagnetic environment. Such discharges may be caused by damage incurred during cable installation or by assembly defects. This publication aims to highlight suitable strategies for selecting appropriate sensors, choosing optimal measurement locations, and optimizing the measurement setup to enable the most reliable possible interpretation of PD patterns and their origins.