Multi machine power system identification by using recursive least square method

Abstract

Electric power systems are nonlinear and complicate in nature. Along with increasing size of power systems, their complexity becomes more. Besides, by using additional and auxiliary components such as Flexible AC Transmission Systems (FACTS) devises, Power System Stabilizers (PSSs), excitation systems, turbine-governor systems and etc, the dynamic model of network is increased and power system becomes more complicate. The nonlinear dynamic model of these large power systems is easily obtained. But, the complexity makes it difficult to obtain a linear dynamic model of power system. Obtaining an appropriate linear model is necessary in order to analysis and study of power system. In tradition method, a linear dynamic model of power system is obtained by linearization of nonlinear dynamic model around an operating condition. But in large electric power systems, the linearization technique is very sophisticate and maybe impossible. Concerning this matter, in this paper a Recursive Least Square (RLS) technique is used to parameter identification in a multi machine electric power system. In this method a linear model is assumed for power system and its parameters are accurately computed by using RLS method. In order to verifying the results, the obtained linear model is compared with the nonlinear model. The simulation results show the validity of identified model, as the response of identified linear model is very near to nonlinear model.