基于开环电压扫频的永磁同步电机电流环参数自校准方案

The resistive model parameters and controller delay of permanent magnet synchronous motor play an important role in the setting of current loop controller parameters. Therefore, a current loop parameter calibration scheme based on open-loop voltage sweep was proposed. Through the frequency sweep signal injection in the rotating coordinate system, the mismatch degree of the motor resistance parameters was determined according to the Bode diagram information of the frequency sweep object. At the same time, considering the influence of inverter nonlinearity and sampling error on calculation, the inverter equivalent model and least square method were applied to the proposed parameter calibration and delay identification. The open-loop voltage frequency sweep not only avoids the problem of selecting the initial value of current loop controller in parameter identification, but also presents the measured current loop transfer function model through the Bode diagram of frequency sweep, which provides a basis for subsequent controller design. Experiments were carried out on a 750 W permanent magnet synchronous motor, and the experimental results fully demonstrate effectiveness of the proposed method.