Internal combustion engines have dominated the world of vehicles for decades, owing to their robust and dependable power. However, they also have several environmental issues, such as low energy efficiency, high power consumption, and inevitable emissions. Concerns about the environment, as well as government incentives, are driving up demand for electric vehicles. The electric machine is the most essential part of any electric vehicles. Interior permanent magnet synchronous motors are chosen over other types of motors because of their high power density and compact size. Nonetheless, these motors have a complex construction, making peak potential exploitation challenging. Several control methods have been devised in an attempt to maximize motor output power and performance and operate it safely, effectively, and consistently. The widely applied controller can be named such as Field-Oriented Control, Direct Torque control or other advanced techniques to enhance performance. Each of them has perks and disadvantages.
In this study, a novel Direct Flux Control is proposed as a promising controller for interior permanent magnet synchronous motor functioning across an extensive speed range. The controller's standout features are its ability to maintain the motor's constant power speed range and the high-speed capabilities of its control scheme. To meet the controller's criteria, the motor's high-speed functioning is investigated through literature review, analysis, and development. One of the most serious concerns is the pull-out torque situation, which will be discussed in detail to figure out the causing of failure in high-speed operation of the motor. The recommended method for achieving the maximum power of the motor is then described, simulated, and executed for verification and assessment.

[1] A. Emadi, Y. J. Lee, and K. Rajashekara, "Power Electronics and Motor Drives in Electric, Hybrid Electric, and Plug-In Hybrid Electric Vehicles," IEEE Transactions on Industrial Electronics, vol. 55, no. 6, pp. 2237-2245, 2008, doi: 10.1109/TIE.2008.922768.
[2] "Global electric passenger car stock, 2010-2020," https://www.iea.org/reports/global-ev-outlook-2021/trends-and-developments-in-electric-vehicle-markets, 2021.
[3] B. Bilgin et al., "Making the Case for Electrified Transportation," IEEE Transactions on Transportation Electrification, vol. 1, pp. 1-1, 06/01 2015, doi: 10.1109/TTE.2015.2437338.
[4] M. Zeraoulia, M. E. H. Benbouzid, and D. Diallo, "Electric Motor Drive Selection Issues for HEV Propulsion Systems: A Comparative Study," IEEE Transactions on Vehicular Technology, vol. 55, no. 6, pp. 1756-1764, 2006, doi: 10.1109/TVT.2006.878719.
[5] T. A. Huynh and M.-F. Hsieh, "Performance Analysis of Permanent Magnet Motors for Electric Vehicles (EV) Traction Considering Driving Cycles," Energies, vol. 11, no. 6, p. 1385, 2018. [Online]. Available: https://www.mdpi.com/1996-1073/11/6/1385.
[6] Y. Inoue, S. Morimoto, and M. Sanada, "Comparative study of PMSM Drive systems based on current control and direct torque control in flux-weakening control region," in 2011 IEEE International Electric Machines & Drives Conference (IEMDC), 15-18 May 2011 2011, pp. 1094-1099, doi: 10.1109/IEMDC.2011.5994754.
[7] K. Jang-Mok and S. Seung-Ki, "Speed control of interior permanent magnet synchronous motor drive for the flux weakening operation," IEEE Transactions on Industry Applications, vol. 33, no. 1, pp. 43-48, 1997, doi: 10.1109/28.567075.
[8] M. F. Rahman, L. Zhong, and L. Khiang Wee, "A direct torque-controlled interior permanent magnet synchronous motor drive incorporating field weakening," IEEE Transactions on Industry Applications, vol. 34, no. 6, pp. 1246-1253, 1998, doi: 10.1109/28.738985.
[9] S. Ekanayake, R. Dutta, M. F. Rahman, and D. Xiao, "Direct torque and flux control of interior permanent magnet synchronous machine in deep flux-weakening region," IET Electric Power Applications, vol. 12, no. 1, pp. 98-105, 2018, doi: https://doi.org/10.1049/iet-epa.2017.0147.
[10] T. H. Nguyen, "Design of 10kW Interior Permanent Magnet Motor for EV Traction," 2016.
[11] F. Mohd Zaihidee, S. Mekhilef, and M. Mubin, "Robust Speed Control of PMSM Using Sliding Mode Control (SMC)—A Review," Energies, vol. 12, no. 9, p. 1669, 2019. [Online]. Available: https://www.mdpi.com/1996-1073/12/9/1669.
[12] G. Zhang, L. Gao, H. Yang, and L. Mei, "A novel method of model predictive control on permanent magnet synchronous machine with Laguerre functions," Alexandria Engineering Journal, vol. 60, no. 6, pp. 5485-5494, 2021/12/01/ 2021, doi: https://doi.org/10.1016/j.aej.2021.03.035.
[13] A. Yoo and S. Sul, "Design of Flux Observer Robust to Interior Permanent-Magnet Synchronous Motor Flux Variation," IEEE Transactions on Industry Applications, vol. 45, no. 5, pp. 1670-1677, 2009, doi: 10.1109/TIA.2009.2027516.
[14] G. Choi, M. Kwak, T. Kwon, and S. Sul, "Novel Flux-Weakening Control of an IPMSM for Quasi Six-Step Operation," in 2007 IEEE Industry Applications Annual Meeting, 23-27 Sept. 2007 2007, pp. 1315-1321, doi: 10.1109/07IAS.2007.204.
[15] L. Zhong, M. F. Rahman, W. Y. Hu, and K. W. Lim, "Analysis of direct torque control in permanent magnet synchronous motor drives," IEEE Transactions on Power Electronics, vol. 12, no. 3, pp. 528-536, 1997, doi: 10.1109/63.575680.
[16] T. Lixin, Z. Limin, M. F. Rahman, and Y. Hu, "A novel direct torque controlled interior permanent magnet synchronous machine drive with low ripple in flux and torque and fixed switching frequency," IEEE Transactions on Power Electronics, vol. 19, no. 2, pp. 346-354, 2004, doi: 10.1109/TPEL.2003.823170.
[17] G. S. Buja and M. P. Kazmierkowski, "Direct torque control of PWM inverter-fed AC motors - a survey," IEEE Transactions on Industrial Electronics, vol. 51, no. 4, pp. 744-757, 2004, doi: 10.1109/TIE.2004.831717.
[18] G. Pellegrino, R. I. Bojoi, and P. Guglielmi, "Unified Direct-Flux Vector Control for AC Motor Drives," IEEE Transactions on Industry Applications, vol. 47, no. 5, pp. 2093-2102, 2011, doi: 10.1109/TIA.2011.2161532.
[19] G. Pellegrino, E. Armando, and P. Guglielmi, "Direct-Flux Vector Control of IPM Motor Drives in the Maximum Torque Per Voltage Speed Range," IEEE Transactions on Industrial Electronics, vol. 59, no. 10, pp. 3780-3788, 2012, doi: 10.1109/TIE.2011.2178212.
[20] B. Boazzo and G. Pellegrino, "Model-Based Direct Flux Vector Control of Permanent-Magnet Synchronous Motor Drives," IEEE Transactions on Industry Applications, vol. 51, no. 4, pp. 3126-3136, 2015, doi: 10.1109/TIA.2015.2399619.
[21] A. Varatharajan, G. Pellegrino, and E. Armando, "Direct Flux Vector Control of Synchronous Motor Drives: Accurate Decoupled Control With Online Adaptive Maximum Torque Per Ampere and Maximum Torque Per Volts Evaluation," IEEE Transactions on Industrial Electronics, vol. 69, no. 2, pp. 1235-1243, 2022, doi: 10.1109/TIE.2021.3060665.
[22] A. Varatharajan, G. Pellegrino, and E. Armando, "Direct Flux Vector Control of Synchronous Motor Drives: A Small-Signal Model for Optimal Reference Generation," IEEE Transactions on Power Electronics, vol. 36, no. 9, pp. 10526-10535, 2021, doi: 10.1109/TPEL.2021.3067694.
[23] G. Pellegrino, E. Armando, and P. Guglielmi, "Direct Flux Field-Oriented Control of IPM Drives With Variable DC Link in the Field-Weakening Region," IEEE Transactions on Industry Applications, vol. 45, no. 5, pp. 1619-1627, 2009, doi: 10.1109/TIA.2009.2027167.
[24] A. Shinohara, Y. Inoue, S. Morimoto, and M. Sanada, "Direct Calculation Method of Reference Flux Linkage for Maximum Torque per Ampere Control in DTC-Based IPMSM Drives," IEEE Transactions on Power Electronics, vol. 32, no. 3, pp. 2114-2122, 2017, doi: 10.1109/TPEL.2016.2569140.
[25] H. Kim, S. Sul, H. Yoo, and J. Oh, "Distortion-Minimizing Flux Observer for IPMSM Based on Frequency-Adaptive Observers," IEEE Transactions on Power Electronics, vol. 35, no. 2, pp. 2077-2087, 2020, doi: 10.1109/TPEL.2019.2920691.
[26] R. Zhao, Z. Xin, P. C. Loh, and F. Blaabjerg, "A Novel Flux Estimator Based on Multiple Second-Order Generalized Integrators and Frequency-Locked Loop for Induction Motor Drives," IEEE Transactions on Power Electronics, vol. 32, no. 8, pp. 6286-6296, 2017, doi: 10.1109/TPEL.2016.2620428.
[27] W. Xu and R. D. Lorenz, "Reduced Parameter Sensitivity Stator Flux Linkage Observer in Deadbeat-Direct Torque and Flux Control for IPMSMs," IEEE Transactions on Industry Applications, vol. 50, no. 4, pp. 2626-2636, 2014, doi: 10.1109/TIA.2014.2298554.
[28] S. Ekanayake, R. Dutta, M. F. Rahman, and D. Xiao, "Deep flux weakening control of a segmented interior permanent magnet synchronous motor with maximum torque per voltage control," in IECON 2015 - 41st Annual Conference of the IEEE Industrial Electronics Society, 9-12 Nov. 2015 2015, pp. 004802-004807, doi: 10.1109/IECON.2015.7392851.