Parameters optimization of excitation system based on extended Heffron-Philips model

Control mode and control parameters of the excitation system play an important role in the security and stability operation of generator and even power grid. It is shown in some generator oscillation accidents without system fault in industrial enterprises that there have exciter stability problems in industrial power plants. In this paper, an extended Heffron-Philips model considering Var and power factor excitation system was established to analyze such the excitation system stability problem. And then with the system characteristics matrix system characteristics root will be carried out to study the principle factors on excitation system stability. A parameter optimal method for excitation system considering local power system small signal stability was proposed based on system root locus. The mechanism of abnormal oscillation without system fault occurred in actual industrial power grid was analyzed and the excitation control parameter was redesigned using the proposed method, which was verified by simulation results.