Simultaneous Optimization of SMES Coil Size and Control Parameters for Robust Power System Stabilization

As the coil size is the heart of superconducting magnetic energy storage (SMES), the simultaneous optimization of coil size and control parameters of SMES for robust power system stabilization is proposed. The structure of active and reactive power controllers of SMES is the practical first-order lead/lag compensator. To handle system uncertainties such as various generating and loading conditions, unpredictable network structures etc., the multiplicative uncertainty model is embedded in the system modeling. As a result, the optimization problem of SMES coil size and controller parameters based on the enhancement of system damping and robust stability margin against system uncertainties can be formulated. Solving the problem by a particle swarm optimization, both optimal coil size and controller parameters are obtained simultaneously and automatically. Simulation study in the West Japan six-area interconnected power system with two SMES units confirms the superior robustness and damping performance of the proposed SMES controller with an optimal coil size under various situations in comparison with the conventional SMES controller.