Pulse-Sine Voltage Injection Based D-Q Axis PMSM Parameter Identification Strategy

The PI parameters tuning of PMSM current loop requires parameter value of stator resistance and d-q axis inductance. However, rotation of motor caused by injection of q-axis voltage will excite the coupling terms in voltage equation, and coupled with nonlinear error of inverter, it will cause significant errors in identification results. To address the above issues, this article proposes a voltage injection method which can prevent excessive rotation of motor during the process of obtaining $L_{q}$ and finish identification within 1 second. First, DC voltage and pulse voltage are respectively injected into d-q axis. Then, inject AC voltage to d-axis to obtain $L_{d}$. Finally, the influence of the nonlinearity of the inverter is weakened by multiple injections and calculations. The effectiveness of the proposed method is validated by experimental results.