AC excitation;  dynamic analysis model;  Generators

According to the basic equation of AC excitation generator with symmetrical rotor structure, combined with the characteristics of the excitation system of this type of motor and the characteristics of asynchronous operation, three adjustment quantities of the excitation system are comprehensively considered: frequency, amplitude and phase angle of the excitation voltage. The angle between the induced potential of rotor flux (current) in the stator winding and the stator voltage is defined as the work angle, and the work angle component and slip rate caused by the difference between the angular frequency of the rotor rotating magnetic field and the synchronous angle frequency are used as state variables, and the fourth-order simplified dynamic analysis model is derived. At the same time, the state equation of the AC excitation generator in the stand-alone infinity system is given, which provides a theoretical basis for the research of the stand-alone infinity system with alternating current.