Flux-weakening control of permanent magnet synchronous motor with direct torque control consideration variation of parameters

Flux-weakening control of interior permanent magnet synchronous motor (PMSM) is elaborated by presentation of current limit trajectory, speed limit trajectory and load angel limit trajectory. Flux-weakening control extends the timing range of the motor. For PMSM, flux-weakening is realized by armature reaction, which is different from induction motor by reducing the flux directly. In flux-weakening range, armature reaction will seriously affect the parameters such as rotor flux, direct axis inductance and quadrature axis inductance. The control trajectories mentioned above and performance of flux-weakening control with and without considering armature reaction are compared realized by MATLAB/SIMULINK. The rationality of theory analysis has been proved by simulation results.