A direct field‐circuit coupled analytical modelling method for permanent magnet motor operation performance analysis

Abstract

In this paper, the analytical relationship among supply voltage, current, and structure parameters of the permanent magnet (PM) motor is cleverly deduced by using an intermediate-flux linkage. After further consideration of boundary conditions, the direct field-circuit coupled analytical model in integrated matrix form is subsequently constructed. Using this model, the vector potentials and currents of the motor can be calculated simultaneously, and the electromagnetic performance, such as the output torque, winding flux linkage, and so on can be further calculated by the vector potentials. Because the control parameters and motor structure parameters are both considered in the derivation process, the proposed analytical model can be used to analyse the motor operation performance under different control strategies. Its validity is finally verified on a 10-pole/12-slot PM motor. The results of the proposed direct field-circuit coupled analytical model are compared with those of field-circuit coupled time-stepping finite element model and experiment under speed-current double closed-loop and current closed-loop control strategies, respectively. The results of the proposed model are proved well with finite element simulation and experimental results.