Optimal Planning of SVCs to Mitigate Voltage Instability in a Network with High Wind Power Penetration

Maintaining voltage stability is a major operating concern in the power systems with significant wind power penetration and large proportion of dynamic loads. This work presents a new approach for optimal location of the Static VAR Compensators (SVCs) and their sizing to mitigate short term and oscillatory voltage instabilities. Depending on the dynamic contingency index, few critical contingencies are picked, and the SVC locations are chosen based on the sensitivity of eigen values to the change in reactive power injections for these contingencies. The sizes of the SVCs are determined by formulating an optimization problem. A combination of Particle Swarm Optimization (PSO) and Sequential Quadratic Programming (SQP) is used to solve the optimization problem. In addition, the damping of the electromechanical modes are also improved by designing a supplementary controller for the SVCs. The presented approach is implemented on IEEE 39 bus test system and results are validated using transient simulations.