Direct Look-Up Table Method for Field-Weakening Control of Permanent Magnet Synchronous Motor Based on Operation Conditions

To operate a permanent magnet synchronous motor (PMSM) in the field-weakening region, the voltage closed loop is the most common method with strong robustness and stability. However, the coefficients tuning of the additional PI regulator is a complex work because of no suitable theory. Also, it stills lead to instability if the coefficients are not appropriate. To solve it, a direct look-up table method is proposed for PMSM field-weakening control without using additional PI regulator. Through the relation of speed, torque and
$\boldsymbol{d}-\mathbf{axis}$
current, a look-up table is designed to generate the required
$\boldsymbol{d}-\mathbf{axis}$
current reference, which can be adjusted dynamically according to different operation conditions. Compared to the traditional one, the proposed method has better current rapidity and stability to some extent, which is verified through experiments.