Flux-weakening control of PMSM for washing machine applications

The flux-weakening control strategy must be adopted in the PMSM control system to meet the wide speed range need of washing machine and other applications. In comparison with the traditional flux-weakening control strategy, a flux-weakening voltage control loop is added to compensate the cross-axis current command in this paper. A simplified and easily implemented overmodulation algorithm is proposed, which can generate greater torque for the motor. In order to save costs, the rotor magnetic pole position is detected by the hall sensors, while the phase current is measured by two shunts in the low leg of the IGBT. Experimental results show that the proposed control system has more wide speed range, good dynamic and static characters and strong anti-interference ability, the system has good practical value.