In this paper, aiming at the problems that the existing stator flux trajectory tracking control method often needs to design complex fundamental wave component observers and the switching time correction based on steady-state solution lacks accurate theoretical calculation equations, a permanent magnet synchronous motor stator flux trajectory tracking control method using optimal PWM (Pulse Width Modulation) is proposed. The outer loop is the speed regulator, whose output is combined with the flux linkage of the permanent magnet of the motor as the reference vector of the stator flux linkage. And the motor speed with the rotor position is combined to calculate the amplitude and phase angle of the reference stator voltage vector, which is used to optimize PWM pulse mode and to determine switching action. Meanwhile, the switching time of optimal PWM is corrected in real time through the stator flux deviation to eliminate the deviation between the stator flux reference value and the actual value. This method does not need to estimate the fundamental component of voltage, current or flux linkage. And unlike the traditional vector method, there is no current inner loop, which can significantly improve the dynamic response speed while simplifying the control structure. Simulation and experiments also fully verify the effectiveness of the proposed control method.
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