Scheduling of Spinning Reserve Considering Customer Choice on Reliability

One of the main objectives of power system restructuring and deregulation is to allow customers to select their desired reliability. This paper proposes a new market model where the reserve capacity is scheduled based on the desired risk level of customers, that is recognized by the expected load not supplied (ELNS) index. The reliability constraint in the objective function of reserve procurement is formulated as a function of generation and reserve allocation among the generating units as well as their failure probability. The reserve requirement is determined regarding transmission constraints and load curtailments due to transmission congestion. Therefore, this method produces market-clearing results with the desired probabilistic characteristics. Moreover, it is shown that the load shedding procedure in contingency states affects the assessment of reserve. The Roy Billinton test system (RBTS) and the IEEE reliability test system (RTS) are analyzed to illustrate the technique.