The Condition Based Maintenance Strategy Study Of Substation Equipment Based On Life Cycle Cost

In the substation equipment management, the introduction of idea of the life cycle management, the substation equipment for the life cycle cost management, Innovated management way, co-ordinate safety, efficacy and cycle cost deal with the relationship between the three, Improve equipment reliability, economy, maintainability, to play their best efficiency, achieve the target of substation equipment life cycle cost at lowest possible total cost.In this paper,analyzing cost compositon of substation equipment life cycle cost, the life cycle costs of substation equipment divided into cost of investment, cost of operation, cost of maintenance, cost of failure, cost of discard five categories, and subdividing cost factor of every kind of cost, established the life cycle cost model of substation equipment. For example in a power transformer, analyzing failure mode and effect of transformer, establishing the model of a single power transfonner failure rate. Fuzzy analytic hierarchy process (FAHP) is utilized to determine the importance degree of each event, and the reliability of58power transfonner of same voltage grade in certain area is calculated. Count corresponding relations between operated year and the failure rate, then Marquardt method is utilized to estimate the parameter of two-parameter Weibull distribution function, thereby obtaining the cut-off of failure rate and the distribution curve function of failure rate.Through the calculated acceptable risk, get the cut-off failure rate of transformer maintenance,the age reduction factor of equipment preventive maintenance, according to the principle of transformer aging, establish the number of age reduction factor based on different maintenance frequency.Express effects of transformer failure rate change in whole life cycle, descripting the change of failure rate before and after equipment maintenance, which reveals the dynamic changing of failure rate depend on the equipment preventive maintenance in life cycle. With the minimum pension costs as optimized object, the optimum life cycle and the best maintenance strategy of this specific type of transformer can be assessed finallyThrough the case study, the analysis method can provide data support for short and long technical improvement plan and strategy in the electric power enterprise.To guide the maintenance and determine the best maintenance projeet has a great significance. Also finally provide technical support for life cycle of the substation equipment management.