A User’s Experience: Automated Fault Analysis System In Identifying Lightning Outages on Transmission Lines

A fault on power lines can cause significant damage to the lines, resulting in outages and other disruptions. Detecting and diagnosing faults promptly are critical to minimise downtime and reduce the costs associated with repairs and maintenance on the transmission line assets. An experience sharing on the application of Automated Fault Analysis system (AFA) developed by TNB Grid to identify lightning-caused tripping is explained in this paper. The AFA involves the process of analysing electrical data obtained from the protection relay system, its sequence of event (SOE) and lightning data from the lightning detection system network (LDSN). The fault location is estimated based on either single-end or two-end fault-locating method. Essential information used and the result obtained from AFA are mapped geographically unto an ArcGIS platform for easier visualisation. Details of the simplified analysis are made available via graphic-user interface, ready to be used by the maintenance team. The objective of the application is not only to establish/verify trippings which have been caused by lightning, but also to locate and identify the associated lightning activities or strokes as accurately as possible. Such data provides valuable information especially in assisting engineers to decide the most suitable mitigation action towards preventing or reducing the chances of fault recurrence, particularly at the same location. This in turn helps TNB Grid to reduce power outages and consequently improve system reliability. An automated self-developed system leveraging on advanced technology such as analytics tool and digital integration with the existing relay system, AFA has proven useful in detecting and diagnosing faults, hence significantly reducing possible future downtime from effective mitigation action and its associated maintenance costs.