New Current Trajectory for Field Weakening Control of PMSM in Wide Speed Range

Permanent Magnet Synchronous Motors (PMSMs) have received great attention recently. Many industrial applications require PMSM to operate in the constant power range above the rated motor speed, called the field-weakening region. In this paper, a new current trajectory is proposed to enhance the dynamic performance of the PMSM in the field-weakening region. This is accomplished by selecting a predefined value of the direct axis current from a Lookup Table (LUT) according to the desired speed then a transition between this value and the optimum required current takes place in order to improve the dynamic performance of the overall drive system. The system is simulated using Matlab/Simulink and tested experimentally to confirm the effectiveness of the proposed trajectory.