Optimal sparing strategy for substation components

A method is proposed to optimize the number of spare items of substation components which have to be stored at the beginning of each year throughout a planning period. This sparing policy is conceived to provide the minimum total cost consisting of investment and load curtailment costs. The method uses the Hooke & Jeeves direct search optimization approach. Analysis performed for two typical substation arrangements clearly shows that the application of the proposed optimization method can substantially decrease the total cost. The comparison of different sparing concepts for substation components indicates that the substation costs are substantially sparing-sensitive, particularly if the power supply redundancy is limited and the cost per kilowatthour not served is high