Energy-based Control Of Power Systems With Svc And Nonlinear Loads

As one of the most effective voltage support equipments, static var compensator (SVC) has been increasingly applied in modern power systems. It is very important to extensively utilize SVC to improve the transient stability of the power systems by the means of advanced control. Based on the thorough analysis of the dynamic compensate principle of FC-TCR (Fixed Capacitor Thyristor Controller Reactor) SVC, this dissertation presents a differential algebraic equation model for the power system equipped with SVC and nonlinear loads and discuss the energy-based stabilization of the system. The main contribution of the dissertation can be summarized as follows:First, the energy-based control of nonlinear differential algebraic systems is discussed. The sufficient condition to complete constant dissipative Hamiltonian realization is given, which also suggest a process to complete the Hamiltonian realization of the system. The stability and feedback stabilization of a Hamiltonian realizable nonlinear differential system is also discussed.Second, the energy-based stabilization of the power system with SVC equipment and constant power nonlinear loads is addressed. The dissipative Hamiltonian realization of the system is completed with the assistant of pre-feedback control. Based on the proposed dissipative Hamiltonian realization configuration, a nonlinear SVC controller is put forward via damping injection.Third, we investigate the coordinated control of generator excitation and SVC in power systems with nonlinear loads and construct an energy-based coordinated controller based on the dissipative Hamiltonian realization of the system.Finally, in order to show the effectiveness of the proposed controllers, we construct a four-node power system with SVC and nonlinear loads based on the Matlab Power System Toolbox and simulate the system under the proposed energy-based nonlinear SVC controllers and conventional PID controllers. The simulation results show that nonlinear SVC controller can effectively improve the transient angle stability and voltage stability.Due to the effective utilization of the internal structure of the power system, the proposed SVC controllers have the advantage of simple formulation and clearly physical meaning. The results got in the dissertation have some signification in the energy-based stabilization control of power systems.