A study on nonlinear SVC control for improving power system stability

This paper presents a detailed analysis of two kinds of nonlinear controllers of static VAr compensators (SVCs). Nonlinear SVC controllers are designed employing the direct feedback linearization theory. It is pointed out that SVCs with only voltage control are able to maintain the voltage at their location but cannot produce additional damping torque to the system. By improvement of the nonlinear SVC voltage controller, a new signal modulation type synthetic nonlinear SVC controller has been developed. The synthetical nonlinear controller is able to produce additional damping torque as well as maintain the voltage at an SVC location. Digital simulation results support the analysis of the paper.<>