Understanding failure modes and Mitigations for Overhead HV Transmission Lines
A.P. Purnomoadi, N.W. Priambodo, A.S. Surya, H.B. Tambunan, A.H. Syarief, K.M. Tofani, M. Ridwan

PLN Research Institute

Abstract

Transmission lines are responsible to deliver the electricity from power plants to customers. In Indonesia, most of the High Voltage (HV) lines are the overhead lines (OHL) that use bare conductors. Cheaper installation cost in comparison to the Underground Cable (UGC) is the main reason why OHL was selected. However, OHL is more prone to disturbances from its surrounding. Over the years, lightnings were suspected as the main reasons of interruptions, followed by the vegetations and social encroachments along the lines. Besides, catastrophic failures have also been reported. These failures include tower collapsed, broken conductors, and broken insulators. These failures contribute to long interruptions, and high corrective costs. Therefore, should be avoided by correct design, operation, and maintenance strategies. This paper presents different triggers that may lead into interruptions based from historical data of over 800 High Voltage OHL in Java and Bali. Follows to that, the deterioration of OHL components and the possible inspections and diagnostics to avoid a catastrophic failure, are discussed. An insight into the risk-based maintenance strategy for overhead lines also provided in this paper.

Keywords: Overhead Line; Transmission Line; Failure Mode; Risk-based Maintenance

Topic: Electrical Engineering