PMSM stator flux linkage weak magnetic given method

The invention discloses a PMSM (permanent magnet synchronous motor) stator flux linkage weak magnetic given method. The method comprises steps that, a rated rotating speed of a PMSM is contrasted with an actual rotating speed, if the actual rotating speed is higher than the rated rotating speed, according to parameters provided by a production manufacturer, or a mutual inductance flux linkage is calculated, difference of the given rotating speed and the actual rotating speed is inputted to a PI adjuster, output is taken as a d-axis current id for excitation control, the difference of the given rotating speed omegaref and the actual rotating speed omega is processed through a PI_2 adjuster, a given torque Te is outputted, difference between the given torque Te and an actual torque Te is processed through a PI_3 adjuster, and the output is taken as a current q-axis component iq for torque control. Self-inductance flux linkages of a d axis and a q axis in a d-q coordinate system are calculated, and a given stator flux linkage amplitude can be calculated according to the mutual inductance flux and the self-inductance flux linkage. The method is simple and effective, the internal structure of the motor and control system hardware are unnecessary to change in a realization process, the control process is easier to realize, a motor speed regulation scope is effectively expanded, and motor production cost and control cost are reduced.