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

Abstract

This article proposes a modulated dual-voltage-vector model-free predictive current control with online duty cycle calculation, which is used to drive synchronous reluctance motors. The dual-voltage-vector modulation scheme reduces the current ripples and current errors present in the single-voltage-vector. 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 current, reducing the maximum average current error by 34.8% compared to its conventional single-voltage-vector one. Finally, the correctness and feasibility of the modulating model-free predictive current controller with the online duty cycle calculation proposed in this article are verified by the experimental results using Texas Instruments micro-controller TMS320F28379D.