Excitation Controller Using Iterative Learning Control Based On Lazy Learning Method

Iterative learning control(ILC) is an novel control arithmetic,which doesn't depend on the precise mode.It can generate input signal and reduce error through repeating learning so that the output of the system can approximate to the expectation. How to choose the appropriate initial control input value for the system (the control input when the first iteration) is one effective way to make the system achieve the desired trajectory tracking in high-precision using less iterations.A method is proposed to solve the problem of the initial control input using lazy learning method.In the power system,excellent excitation control system can not only guarantee reliability and stability of generator's,but also improve effectively technique and economic characteristic of the generator and its joined power systems.It is good to stability improvement in power system.Based on the mechanism of ILC,the applications to excitation control of synchronous machine with considering high nonlinearities,strong coupling are studied in this dissertation.Excitation control is realized with ILC,so dynamic performances such as immoderate modulation restraint,faster convergence and shorter transition times are improved.A new excitation controller of synchronous generator is developed by iterative learning control based on lazy learning method in the dissertation.A method is proposed to solve the problem of the control input using lazy learning method.The proposed method increases the convergence speed greatly when tracking a desired trajectory.Using the Simulink toolbox in Matlab the simulation for single machine infinite bus system and that for two-machine system are carried out.Simulation results show that the proposed control method is effective and versatile.That the designed controller,compared with traditional PID controller and the controller with the single method,the convergence speed of the proposed control law is visibly higher and can maintain the terminal voltage of generator on constant value.The stability of power system could be improved by use of this control strategy.