Performance improvement of parallel dual-star permanent magnet synchronous machines via type-2 fuzzy direct torque control with a single six-phase inverter

Introduction. The growing need for efficient and high-performance electric drive systems has led to increased research in advanced control strategies for multi-machine configurations. Among them, dual-star permanent magnet synchronous machines (DSPMSMs) connected in parallel to a single inverter offer a promising solution for applications requiring high reliability and precise control. Problem. Conventional direct torque control (DTC) strategies, typically relying on PI controllers, suffer from significant torque and flux ripples, which negatively impact system efficiency and dynamic response. Moreover, these traditional controllers face challenges in handling parameter variations and external disturbances, limiting their applicability in demanding environments. Goal. This study aims to enhance the performance of DSPMSM drive systems by improving speed regulation, minimizing torque and flux fluctuations, and increasing robustness against disturbances, thereby ensuring greater efficiency and stability. Methodology. To address these challenges, we propose a novel DTC strategy that replaces the conventional PI controller with a type-2 fuzzy logic controller (T2-FLC). This intelligent control approach leverages the adaptability of fuzzy logic to improve response accuracy and dynamic performance. The proposed methodology is validated through extensive simulations using MATLAB/Simulink, analyzing various operating conditions and comparing the performance with conventional DTC techniques. Results. Simulation results confirm that the T2-FLC-based DTC significantly reduces torque and flux ripples while ensuring precise speed regulation. The proposed approach also demonstrates improved robustness against disturbances and parameter variations, outperforming traditional PI-based DTC in terms of efficiency and control accuracy. Scientific novelty. This research introduces an innovative application of T2-FLC in DTC for parallel-connected DSPMSMs, offering a novel control strategy that effectively mitigates the drawbacks of conventional methods. The integration of T2-FLC into the DTC framework provides enhanced adaptability and superior performance, distinguishing this study from existing works. Practical value. The proposed control strategy enhances the reliability, efficiency, and stability of DSPMSM-based drive systems, making it well-suited for high-performance applications such as railway traction, electric vehicles, and industrial automation. By improving control precision and robustness, this approach contributes to the advancement of intelligent drive technologies in modern electric propulsion systems. References 39, tables 4, figures 16.