Researches On The Damping Characteristics And Optimization For Synchronous Generator Excitation

The control of excitation system of synchronous generator plays an important role inthe security and stability operation of the power system. As the rapid development of thepower system, higher requirements are put forward for the control of the excitation system.Therefore, more research on the optimal design of the excitation controller is an importantissue for large grid interconnection and the construction of higher level of power grid.The optimization and application of the excitation controller was research in this paper.Firstly, the damping mechanism of the excitation system and power system stabilizer wasanalyzed by using the concept of combing synchronous torque and damping torque, whichverified the adverse effect that fast and high ratio of excitation system makes on the powersystem and the excellent performance of the linear optimal excitation controller. Meanwhile,the influence that the excitation system and power system stabilizer made on synthetictorque was studied and the frequency and the excitation system parameters effect on thesynchronous torque and damping torque were analyzed. Base on these, the effect of PSSparameters optimization was be checked in the Huazhong Power Grid. Then base on theprinciple of phase compensation, using genetic algorithm, parameters optimization for PSSwas be researched, and it has been applied in the Huazhong Power Grid. The applicationshows that the PSS parameter optimization effectively improved the damping ratio of theHuazhong Power Grid, and was conducive to the security and stability operation. In additionof this, a method of dynamic equivalent for excitation controller optimization was presented,that the units out of the system would be equivalent to a parallel unit with an infinite systemand a parallel unit with a dynamic generator. The dynamic equivalent unit parameters werevalidated by using recursive least squares method. At last, the equivalent results wereverified.