The invention discloses a parameter identification method for a
permanent magnet synchronous motor in a steady-state
operation mode. The method comprises the steps of: firstly carrying out sampling when the motor is in a steady-state operation state to obtain a direct-axis
voltage, a quadrature-axis
voltage, a direct-axis current, a quadrature-axis current and an electromechanical angular speed; after short-time current is injected into the direct axis, extracting the five variables again to construct a parameter identification equation; then, analyzing
voltage error and three-phase current
harmonic problems caused by nonlinearity of an
inverter; setting the compensation time to adjust the on-off of a switch tube, reducing the nonlinear influence of the
inverter, and improving the overallparameter identification precision; and finally, since the identification result of
inductance depends on the direct-axis voltage to a great extent, further improving the identification precision of the
inductance through a feedforward
compensation algorithm. According to the method, the voltage error caused by the nonlinearity of the
inverter can be effectively compensated, the content of the fifth and seventh
harmonics of the three-phase current is obviously reduced, the resistance,
inductance and permanent
magnet flux linkage values can be identified more quickly and precisely, and the control performance of the
permanent magnet synchronous motor is improved.