This paper presents a dynamic model for quadrupole six-phase electrical excitation synchronous wind power system. Capacitor charge-discharge process is taken into consideration, as well as transmission chain speed conversion and generator electromagnetic transformation. Based on PI control principle, controllers dynamic model is established to keep DC voltage constant and realize the maximum power point tracking (MPPT) and unity power factor output. And then, the circuit model is built with Matlab/Simulink. On the basis of the least square method, the relationship between uncontrollable rectifier reactive consumption (Qr) and active output (Pr) is fitted. Finally, a grid-connected WTG operation performance is studied and compared with circuit model simulation, which verify the validity of the proposed model. (6 pages)