Optimal sparing strategy for a group of substations

The authors derive a method to optimize the sparing of the equipment for a group of substations during a planning period. The amount of spares which have to be stored at the beginning of each year is optimized to achieve the minimum total cost associated with sparing, which includes the investment cost for spares and the load curtailment and loss of revenue costs. Various sparing strategies are evaluated, including common and individual-inventory concepts. The application of the method and the benefits it provides when compared to other sparing concepts are demonstrated for several typical examples.