Integrated application of SSSC and SMES to improve power swings damping based on direct Lyapunov method

A new approach is presented to improve power swings damping of nonlinear power system model based on direct Lyapunov method. The approach combines superconducting magnetic energy storage (SMES) system with static series synchronous compensator (SSSC). Considering the energy absorption/injection ability of SMES, in transient states the combination exchanges both active and reactive powers with power system. Since direct Lyapunov method implies time derivative of both active and reactive powers, prepares an effective control strategy for the integrated SSSC-SMES system to decrease power swings damping time. Using direct Lyapunov method for structure preserving model (SPM) of power system, dq components of SSSC injecting voltage are calculated. Decentralizing method is used to locally control the SSSC-SMES independent of state variables of synchronous generators which require wide area measurements. PSCAD/EMTDC simulations verify the effectiveness of proposed method.