Static Var Compensator And Nonlinear Control Study

In electric power systems, controling voltage quickly and damping oscillations of power angle vary in many characters, whereas have something to do with each other. How to deal with this contradiction, that is to say, to find a kind of control means having the two functions mentioned above in the meantime, is a big problem.With the development of electronics, system reactive power compensators have evolved from synchronous condensers, series capacitors, shunt capacitors bank, then shunt reactors to Static Var Compensators (SVCs) which support a new strong controlable tool for power systems. Because SVC has outstanding celerity characters of control, there is an important significance to study deeply the control thesis of SVC in improving power angle stability.In this dissertation, fundamental principle, general control mode and many good influences are researched first of all. To overcome the limitations of a linear PID control such as a narrow stable band, bad compatibility and robustness and differential coefficients difficult to be acquired, in this dissertation, selecting Δ_ω as a feedback variable and using the control thesis of TSC, a new nonlinear PID controller for TSC+TCR is designed for Static Var Compensator (SVC). The controller has many good characteristics, such as not dependent on the model of controlled system, having valuable robustness about working point and with the structure of the systems, easy torealize, simple structure and wider adjustable band.The simulation manifests that the controller can not only improve power angle stability and local voltage characteristics of SVC, but also has strong compatibility and robustness because it makes the best of the functions and efficiency of a nonlinear PID control in the feedback loop.