To predict the DC winding induced voltage of the wound field switched flux (WFSF) machine, the mathematical model of the WFSF machine considering harmonics in the DC winding self-inductance L f , and harmonics in the mutual inductance M fx (x=A, B, C) between x-phase armature winding and the DC winding is proposed in this paper. The modelling method decouples each current differential term in the d- and q-axis voltage equations and the DC winding terminal voltage. The control system simulation with the proposed mathematical model is built to verify the accuracy of the modelling method, and the capability to predict the DC winding induced voltage pulsation. Meanwhile, by adopting this mathematical model, finite element analysis can be avoided when conducting the motor control simulation, which can reduce the simulation time cost whilst ensuring the control precision.