A centralized condition monitoring system for MV power cables based on on-line partial discharge detection and location

This paper presents the principles and the first results of a new and unique on-line partial discharge (PD) based diagnostic system for medium-voltage power cables, which enables monitoring the condition of complete cable connections up to several kilometers in length over a long period of time. It allows locating the weak spots along the cable connection and identifying the development over time for each individual location. The system, called PD-OL (PD On-line with Location), covers the complete process from on-line measurement to centralized data processing and obtaining appropriate recommendations regarding all the cable connections monitored. The paper discusses the various principles behind both the measurement technique and the centralized data processing. Furthermore, the experience and results obtained from various pilots with field installations are presented. These results show the functioning of the system, together with its broad applicability.