Performance-driven switched reluctance motor drive using multiport cascaded converter and advanced direct torque control scheme

The switched reluctance motor (SRM) drive exhibits inherent characteristics such as robustness, high efficiency, and fault tolerance that make it particularly well-suited for traction applications. However, SRM drives controlled by specialized converters often produce high torque ripples and harmonic distortion. On the other hand, conventional two-level converters for SRMs increase stress during switching operations. To address these challenges, this paper proposes an enhanced modular multiport cascade converter (MMCC) for SRM drives, aimed at minimising torque ripples and harmonic distortion. By increasing the number of voltage levels, the performance of the SRM drive is improved when combined with an enhanced direct torque control (DTC) strategy. The precise SRM model and the MMCC switching controlled by optimized DTC switching tables are integrated and evaluated using MATLAB/Simulink. The developed model analyzes input current and voltage harmonics across switches during drive operation. The proposed model behaviour for steady-state and dynamic performance is validated through speed, torque, and phase current measurements. A hardware demonstration of the SRM drive under various operating conditions further confirmed enhanced performance. The proposed converter achieves a 41.5% reduction in torque ripple compared to its conventional counterpart, thereby significantly enhancing dynamic performance and demonstrating strong suitability for variable drive applications.