An operation scheme of UPFC´s considering operating objectives and states

This paper presents an operation scheme of UPFCs considering objectives and states of power system operation. Two modes of UPFC operation, an economic mode and a secure mode are proposed according to operating objectives and states. In the economic mode, both the generation cost and the active power loss have been minimized by active and reactive power control of UPFC´s. In the secure mode, the security index J relating to line flows and bus voltages has been minimized by operation of UPFC´s. A decoupled model has been utilized as a mathematical model to evaluate the effect of an UPFC on a system. For verification of the proposed operation scheme, numerical simulations have been performed on a 10-unit, 39-bus New England System equipped with 3 UPFC´s.