Optimum load-shedding technique to reduce the total customer interruption cost in a distribution system

In capacity deficiency conditions caused by unscheduled outages in a generation and transmission system, system operators have to shed load at selected feeders in the distribution system to maintain acceptable operating conditions. Different load-shedding schemes can result in quite different load point reliability performance. Conventionally, the objective is to shed the minimum load subject to system security constraints. An optimum load-shedding technique is presented that can be used to improve the reliability of a local distribution system. Customer concerns regarding interruption costs are considered in the load-shedding procedure. The objective is to minimise the total system interruption cost. Cost weight factors are used to determine the load-shedding priority among feeders, and an enumeration technique is used to divide the capacity deficiency between feeders. The unreliability cost indices of two representative distribution systems are evaluated to illustrate the technique