Analytical method based on magnetic equivalent circuits (MEC) is widely used for the preliminary machine design due to short calculation time and low computational cost, but the calculate result is normally considered to be not as accurate as finite element method (FEM). To address the MEC less accurate and FEM time-consuming challenge, a novel design and analysis procedure of permanent magnet synchronous generators (PMSGs) was proposed in this paper. The initial physical and electromagnetic features of PMSGs were presented by MEC at first design stages, the electromagnetic analyses were realized by FEM based on electromagnetic simulation software. The field-circuit coupled design method could facilitate accuracy and shorten time cycle of the generator design. Using RMxprt as simulation tool had realized the convenient and fast modeling, the parametric analysis of armature diameter, axial length, air gap and number of conductors per slots were carried out. The results show that the magnetic density distribution of the generators becomes better, and the efficiency is improved. The validity and applicability of the method is verified. Moreover, it will provide a basis for the further 3D optimization design of the generators.