javad rahmani fard

Compared with other multiphase machines, dual three-phase machines are able to take advantage of off-the-shelf three-phase inverters. Though the output torque decreases under post-fault conditions, the post-fault control strategies of them are simple, and their post-fault performance is steady. Therefore, the market of dual three-phase machines is promising in the future. In this paper, the design principle, operating characteristics behavior of the dual three-phase machine are investigated. Firstly, the winding arrangement and slot-pole combination of the dual three-phase machine is analyzed. The performance of different schemes iscompared, and the optimal scheme of winding arrangement and slot-pole combination for the dual three-phase machine is proposed. Moreover, the machine adopting the proposed scheme is designed. Secondly, operating characteristics of the dual three-phase machine under healthy conditions is analyzed. The possible fault terms of the machine is summarized. Comparing with conventional constant magnetomotive force, the advantage of the dual three-phase machine is significant. The effectiveness of the theoretical analysis and simulations is validated by the comparison.

The compound-structure permanent-magnet synchronous machine (CS-PMSM) system is a novel drive system used for hybrid electric vehicles (HEVs). In this paper, firstly, the mathematical model of the CS-PMSM motor is examined in detail, and then the control strategy of the CS-PMSM is investigated and established. The CS-PMSM is composed of two permanent magnet synchronous motors: a Double Rotor Machine (DRM) and a Stator Machine (SM). Different control strategies are applied for the two machines. According to their special structures and applications, the DRM performs the torque control, and the SM carries out the speed control. The DRM implements the id=0 control, while the SM carries out the maximum torque per ampere control during the constant torque region, and flux weakening control during the constant power region. Secondly, the direct torque control method is investigated and applied for both machines. The feasibilities of the vector control and direct torque control methods are both validated by the simulation results in the MATLAB/SIMULINK, and these two methods are further compared. The optimum control methods are finally established for the DRM and SM and also the selection of the optimal number of turns for the stator is considered.

In this paper, based on the vector control of axial field flux switching permanent magnet (AFFSPM) motor, an optimized field-weakening control method of AFFSPM motor is proposed. A new AFFSPM motor with 12 stator slots (S) and 19 rotor poles (P) is taken as the object to simulate and optimize the flux-weakening speed control. The AFFSPM motor adopts constant torque control with the maximum torque per ampere below the base speed, which reduces motor losses, improves the efficiency of the inverter and adopts constant power and sub-regional speed control above the rated speed. By combining the cross-axis current and direct-axis current in the flux weakening control method, the power factor of the AFFSPM motor can be improved and speed range can be extended. By considering the speed fluctuation in field weakening control, and the fuzzy self-tuning PI control method is proposed to improve the performance of the AFFSPM motor field weakening control. To verify the feasibility of proposed control method, Co-Simulation is used. Finally, the control algorithm of the drive system is implemented in a prototype of AFFSPM motor.

Fault-Tolerant Hybrid Excited Axial Field Flux-Switching (FT-HEAFFS) motor is a new type of doubly salient stator-type permanent magnet motor, which combines the advantages flux switching motor and hybrid excitation motor. This motor has compact structure, high power density, high efficiency and strong anti-demagnetization capability. The additional excitation winding makes the air gap magnetic field adjustable, which can increase the output torque and extend the speed range. It is suitable for use in the system of frequency conversion and speed regulation of electric vehicles. To improve the performance of the fault-tolerant-hybrid excitation axial field flux-switching (FT-HEAFFS) motor and attain the minimum copper loss, a fault-tolerant control method based on model predictive control algorithm is proposed. Considering a 6 stator slots/13- rotor poles FT-HEAFFS machine as the control object, under the open circuit failure of single-phase winding, the minimum cropper loss fault-tolerant method based on the model predictive torque control (MPTC) and direct torque control are studied and analysed, respectively. The feasibility and effectiveness of the proposed fault-tolerant control method are verified. The research results showed that both methods could make the speed, torque and stator flux-linkage almost unchanged, ensuring the stable operation of the system. Compared with direct torque control, the model predictive flux control had smaller flux-linkage ripple before and after the open circuit failure.

Flux switching permanent magnet synchronous motor (FMSM) has the characteristics such as large output torque, fast speed response and high reliability, so it can be widely used in the field of high-performance and high precision control.In the permanent magnet synchronous motor control system, the speed loop usually adopts the PI control algorithm. Although the PI control algorithm is relatively simple, there is a problem of adjusting the PI parameters, so the traditional PI also has limitations. However, the fuzzy controllers also have a big disadvantage. When the motor load suddenly increases, the fuzzy PI control has difficult to effectively eliminate the system steady-state error, so the control precision is not high, which is mainly due to the lack of integral effect controller. A new fuzzy PI control algorithm for a novel yokeless and segmented armature axial flux-switching sandwiched permanent-magnet motor (YASA-AFFSSPM) is proposed in this paper. In the conventional fuzzy PI control of the permanent magnet synchronous motor the torque ripple is large and the control accuracy is not high precise. A new fuzzy PI control algorithm is proposed to solve this problem, and a prototype of the YASA-AFFSSPM motor is fabricated and the method is tested. The experimental results demonstrate that the new fuzzy PI controller can improve the robustness of the system and improve the precision. Further, the dynamic performance of the YASA-AFFSSPM motor is excellent.

Axial field flux switching motor with sandwiched permanent magnet (AFFSSPM) is a novel of flux switching motor. Based on the vector control method, the mathematical model of the AFFSSPM is derived and the operating performance of the AFFSSPM in the overall operating region is investigated.A novel control method for the AFFSSPM drive system, including the id =0, maximum torque per ampere, constant flux linkage, unity power factor control and flux-weakening strategy, is proposed. A prototype of the 12/19 poles AFFSSPM motor is manufactured and tested. moreover, validity and feasibility of the proposed method were verified by experiments.The AFFSSPM motor is one of the most efficient motors but control scheme of the 12S/19P AFFSSPM motor has not been specially reported to date. Thus, in this paper, we report on the operating performance of the AFFSSPM in the overall operating region is investigated.Recently, suitable configuration and control strategy of the electric machines have been of the important research areas. Characteristics such as high-reliability, high-efficiency and better fault-tolerance capability are required for the EVs. Flux-switching permanent magnet (FSPM) motor attracts an increasingly attention because of its features over conventional rotor-PM motors.]. Although AFFSPM motors offer higher torque density, the torque density is restricted owing to decreased available winding space because in addition to the armature windings, the PMs are placed in the stator. Hence flux switching machines with sandwiched permanent magnet were suggested .