Static VAr compensator control for power systems with nonlinear loads

An accurate linearisation technique for multi-input power systems with nonlinear loads is presented. The nonlinear differential algebraic system (NDAS) considered is not in the state equation form. The definitions of M derivative and M bracket are similar to the definitions in classic differential geometric theory and some related revised results are introduced. M derivative and M bracket are used to obtain the feedback control law for the NDAS. The approach is used to design a nonlinear static VAr compensator (SVC) controller for a single-machine infinite system with nonlinear loads. The simulation results show that the nonlinear SVC controller improves damping and the voltage level to a greater extent than conventional controllers. The control law is even effective when the nonlinear loads are varied.