A quantum direct torque control method for permanent magnet synchronous machines

This study compares classical direct torque control (DTC) methods with a proposed quantum direct torque control (QDTC) strategy for synchronous machines. A quantum comparator is developed by implementing a quantum subtractor between real numbers ranging from -100 % to +100 %, and a quantum sign function is developed using this digital quantum subtractor. The QDTC implementation involved the use of quantum versions of the classic logical AND and OR gates. Simulation results indicate that the QDTC method significantly reduces torque ripple, with a ripple torque factor of 0.0392 compared to 0.0417 for the classical DTC. The QDTC approach also required 5.2 % fewer commutations (9.81 × 104) compared to the classical approach (1.035 × 105), which increases the longevity of the power components. Finally, the total harmonic distortion (THD) was lower for the QDTC method compared to the classical strategy. The results indicate that the proposed QDTC method either matches or surpasses the performance of the classical method across several metrics. Specifically, the reduced torque ripple and commutation frequency leads to smoother motor operation and longer component lifespans, while lower THD is indicative of greater motor efficiency. © 2024 The Author(s)