Abstract: Due to the difficulty of adjusting the air gap magnetic field, it is hard to keep output voltage constant in the operation of permanent magnet synchronous generators. This paper proposed a hybrid excitation brushless synchronous generator in which double-pole induction was applied to produce field excitation in conventional surface mounted permanent magnet generator frame. On the basis of structure analysis, the equivalent magnetic circuit model was established, and the calculation formula of voltage regulation was derived. Magnetic field distribution and the influence of structural parameters on the operation performance of the motor were further studied by using the two-dimensional finite element method. Then the prototype was developed and the no-load and load experiments were carried out. The experimental results verify the rationality of the proposed hybrid excitation motor structure.