| The aggravation of global energy crisis and environmental pollution is intensified by massive fuel consumption and serious exhaust emissions of traditional vehicles, which indirectly promotes the rapid development of electric vehicles (EV). With relatively high torque density and good performance at low speeds, transverse flux permanent magnet motor (TFPMM) has been expected to be a preferred embodiment of direct-drive EV. Therefore, as applied in direct-drive EV, a novel TFPMM designed by our research group is taken as the control object in this paper. And effective control schemes for different levels of application requirements are deeply researched to provide powerful theoretical basis and technical support for its application.Firstly, this paper gives a brief analysis on the basic structure, operating principle and electromagnetic parameters of the novel TFPMM. And the mathematical models of permanent magnet synchronous motor (PMSM) drive and brushless DC (BLDC) drive are respectively established as the foundation for control of the novel TFPMM.The next research work starts with open-loop control applications. In reference to practical application, the comparable investigations on the two drive modes (namely PMSM and BLDC drive) are implemented. And it is indicated from comparative results that BLDC drive is much more suitable for novel TFPMM. However, it should be cooperated with phase advance commutation to weaken the influence of armature reaction and shorten the commutation interval, which further improves the performance of the motor. The field test with two prototypes installed in a sample car is carried out to verify the correctness of the conclusion and the feasibility of its application.Furthermore, for open-loop BLDC drive with 120°conduction, a position-sensor approach based on phase advance commutation is proposed to obtain maximum torque per ampere (MTPA). Under varying load torque conditions, the required phase advance angle is automatically calculated by DC bus current and rotor speed, achieving satisfactory performance, including much higer efficiency and much stronger load capacity. Besides, with sensorless control regarded as the actual requirement of EV for much higher reliability, the mechanism of the additional detection error in novel TFPMM is deeply analyzed, which is produced by the phase-voltage method. A corresponding compensation scheme is proposed and then verified through both simulated and experimental results.When the novel TFPMM operates in open loop, relatively large torque ripple is inevitable. However, direct torque control (DTC) can be employed to reduce torque ripple. Hence, to obtain MTPA and reduce torque ripple, this paper presents a new position-sensor DTC based on phase advance commutation. The desired voltage vector is properly selected in terms of both rotor position signals and torque hysteresis comparator, avoiding the problems of stator flux reference and motor starting that exist in conventional DTC. Simulated and experimental results show that the proposed approach is especially suited to the drive applications of the novel TFPMM with relatively good dynamic quality.Sensorless control is still the ideal approach to meet application requirements of EV for much higher reliability. Based on the conventional DTC, direct torque and adaptive flux sensorless control is proposed as a solution to stator flux reference, where the desired voltage vector is only determined by stator flux position and torque hysteresis comparator. However, it should be cooperated with reasonable compensation angle for the difference of optimal phase advance angle and the angle between stator and rotor flux. The proposed sensorless DTC is demonstrated through both simulated and experimental results to avoid the problem of stator flux reference and obtain larger torque per ampere, smaller torque ripple, higher efficiency and stronger load capacity, which is an important technical support for further application of the novel TFPMM in direct-drive EV.
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