Reliability Improvement Opportunity for 115-kV Overhead Transmission Lines Using RCM Method

Provincial Electricity Authority (PEA) has more customers each year because of the economic growth and the expansion of industries in the countryside of Thailand; therefore, the transmission line is constructed for supporting future energy consumption. However, PEA has to face the challenges for preventive maintenance (PM) planning to get cost-effective maintenance of the inherent reliability value under a budget constraint. This paper proposes a reliability improvement opportunity for 115-kV overhead transmission lines using the RCM method. The main proposal of paper is PM planning to get cost-effective maintenance of 115-kV transmission lines using TOPSIS to prioritize the selected transmission lines based on reliability indices consisting of MAIFI, SAIFI, SAIDI, ENS and CAIDI. The weight valuation of each criterion uses Shannon's weight to make the priority by TOPSIS unbiased. Maintenance activities are selected the effective maintenance activities for each failure mode by the B/C between SAIFI deviation and maintenance cost. Therefore, failure mode used the probability of the past four years of the interruption statistics. The study results illustrate the RIO graphs to shows the relationship between maintenance cost and reliability indices for PM planning to get cost-effective maintenance and to control reliability indices values which are the key performance indices (KPIs) under a budget constraint.