Modulated Dual-Voltage-Vector Model-Free Predictive Current Controller for Synchronous Reluctance Motor Drives With Online Duty Cycle Calculation

Abstract

In this paper, a modulated dual-voltage-vector model-free predictive current control with online duty cycle calculation is proposed and applied to drive a synchronous reluctance motor. The dual-voltage-vector modulation scheme reduces the current ripples and errors in the single-voltage-vector method. The proposed method reduces the predictive current controller’s calculation time by first setting the initial value of the duty cycle to a constant. Then, an optimal switching mode can be selected by minimizing a cost function. Next, the required duty cycle can be calculated directly by the proposed method without any differential calculations instead of its initial value. The proposed method can effectively track the stator current, reducing the maximum average current error by 34.8% compared to the conventional single-voltage-vector scheme. Finally, the correctness and feasibility of the modulated model-free predictive current controller with the online duty cycle calculation proposed in this article are verified by the experimental results using Texas Instruments microcontroller TMS320F28379D.