Failure statistics and inventory management for high voltage circuit breaker using statistical distribution techniques

The failure statistics and optimum number of items kept in stock needs primary concern in order to minimize maintenance cost of high voltage equipment. This paper proposes the failure statistics and asset management strategy to optimize number of spare parts of high voltage circuit breaker in transmission network for the effective inventory control. By using Pareto analysis, components of high voltage circuit breaker in the stock are classified into ABC classes. Class A means the few most expensive ones that need special care. Class B means ordinary ones that need standard care. Class C means the large number of cheap items that need little care. Since class A items such as high voltage component of circuit breaker occupy most of the total inventory cost, they are of prime interest. The optimum number of spare parts can be determined from failure records by applying Normal and Poisson distribution techniques. The proposed method can effectively reduce the total inventory cost of the utility. It is further applied with the other high voltage equipment in the system.