Inventory management method to determined spare transformer optimization

This paper present an analysis to determined 500/150 kV spare transformer in Java Bali System. To obtain the desired reliability value, the spare transformer failure rate is determined from the failure rate value. This study uses the method of Inventory Management to get the value of failure rate. Inventory Management and Pareto Law will analyze transformer data such as impedance and location get a classification of transformer. Pareto Law method determined which disturbance of transformer components are the major failure. The failure rate will be calculated using historical data and the classification above. Finally, the spare transformer calculation will be determined using several calculation as a benchmark, the favored calculation or method of this study is Markov Chain Method.