Application of simultaneous active and reactive power modulation of SMES unit under unequal /spl alpha/-mode for power system stabilization

A simple and novel control strategy for damping electromechanical oscillations through control of power converter firing angles /spl alpha//sub 1/ and /spl alpha//sub 2/ of a superconducting magnetic energy storage (SMES) unit is proposed. Both active and reactive power modulations are used under unequal /spl alpha/-mode of operation. The choice of unequal mode is discussed in detail. The gains of the proposed SMES controller are determined once offline depending on the power system and the rating of the SMES unit. Simulation results show that the SMES unit can effectively suppress power system oscillations by utilizing its active and reactive power modulation capabilities. The control algorithm is simple and its realization will require very little hardware.