Parameter Robustness Improvement of Predictive Current Control for Permanent-Magnet Synchronous Motors

Abstract

A predictive current control with parameter robustness (PR-PCC) method of permanent magnet synchronous motor (PMSM) is proposed in this article. First, a cost function is designed to calculate the increment of the optimal voltage vector at the current instant, which is based on incremental PMSM model. The incremental PMSM model is used to eliminate the influence of the motor flux parameter. Second, the optimal voltage vector that minimizes the cost function is obtained by combining the increment of the optimal voltage vector with the idea of iteration. At the same time, a current observer based on the incremental model is designed to compensate one-step sampling delay. In this way, the feedback current of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$dq$ </tex-math></inline-formula> -axis accurately followed the reference current. In comparison with the conventional pulse width modulation predictive current control (PWM-PCC) method, the proposed method can significantly reduce the steady-state error of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$dq$ </tex-math></inline-formula> -axis current caused by inductance, flux, and resistance parameters mismatch quickly. Finally, experimental results of the proposed method and the conventional PWM-PCC are presented in this article to verify the validity of the proposed method.