Field circuit and movement coupled time stepping finite element analysis on permanent magnet brushless DC motors

A time stepping finite element analysis (FEA) model coupled circuit field and movement used in analyzing permanent magnet brushless DC (BLDC) motors is presented in this paper, which can solve the problem of non-sinusoidal power supply in field-circuit coupled FEA. The converting process of switching element operation and electric position fluctuation of the circuit winding neutral point are taken into account in circuit equation. The element analysis about the coupling problem of control circuit and field is researched. An improved moving finite element method, interpolation moving boundary method, is adopted to solve rotation problem. The performance of a BLDC motor is analyzed using above model. The calculation result is very close to the measure results. This method can be used in analyzing other non-sinusoidal power supply machines.