An Improved MTPA Control Method Based on DTC-SVM Using D-Axis Flux Optimization

This paper proposes an improved Maximum Torque Per Ampere (MTPA) control method based on The Direct Torque Control-Space Vector Modulation (DTC-SVM) control algorithm using d-axis flux optimization. The proposed algorithm simplifies the existing DTC-SVM control method by geometrically interpreting its complex equations thereby providing a more straightforward and efficient approach. The proposed algorithm geometrically computes the d-axis flux reference and compensation values for the MTPA control by continuously monitoring the q-axis flux in real time. Additionally, the compensation value of the d-axis flux reference is employed to compute the magnitude and phase reference values of the DTC-SVM voltage vector, which in turn generates the stator current values that align with the MTPA curve. The effectiveness of the proposed algorithm was validated through simulation results in MATLAB Simulink. When the proposed algorithm was applied, the torque response to the torque command improved compared to the DTC-SVM control. Additionally, for the same torque production, the stator current consumption of the IPMSM was reduced by approximately 12.55%, demonstrating improved efficiency. To further validate the effectiveness of the proposed algorithm, a dynamometer test system was established, and the IPMSM was tested across various speed ranges below the base speed while generating different torque outputs. The torque response dynamics and stator current consumption of the proposed algorithm were then compared with those of the DTC-SVM algorithm, confirming its enhanced performance.