In this paper, a multimode design method is proposed for motor design under multiple operation conditions. Based on the driving cycles in electric vehicles, five typical operation conditions and the corresponding five driving modes are determined for the multimode design. To investigate the method conveniently, a flux controllable stator permanent magnet (SPM) memory motor is selected and taken as a design example. In the design process, by using the sensitivity analysis method, the significance of the parameters in various driving modes are evaluated effectively. Based on the motor driving demands, the whole optimization design is divided into three steps, where different optimization method is applied in each step. To verify the feasibility of the multimode design method, the operation performances of the motor in different driving modes are investigated in detail. Finally, a prototype motor is built and tested. Both the simulation and experimental results reveal that the proposed design method can offer an effective design optimization for the flux-controllable SPM memory motor, where multimode operations are indispensable.

An active disturbance rejection control (ADRC) controller using phase-locking loop observer (PLLO) is proposed in this paper to improve the disturbance rejection property of speed control system. Firstly, to simplify the comparison with other controllers, a universal speed controller design method based on disturbance estimation is employed, and a unified expression for different controllers is presented. Then, several common speed controllers are compared with each other, and two PLLO based ADRC controllers are presented. After that, considering the variations of load inertia, robustness of the proposed ADRC system to inertia variation is analysed. Finally, to improve the tracking performance for sinusoidal speed-reference, an adaptive speed control system using identified inertia is presented. Simulation and experimental results verified the effectiveness of the proposed method.

In this paper, two permanent magnet flux-intensifying motors are designed and optimized to realize the characteristic of Ld > Lq and the flux-intensifying effect. Compared with the conventional interior permanent magnet motor with the characteristic of Ld< Lq, the advantages of a low irreversible demagnetization risk and a wide speed range can be obtained in the motors. To meet multiple design requirements effectively, a comprehensive sensitivity analysis method is first implemented to evaluate the influence of each design variable on the selected optimized objectives of output torque, reverse saliency ratio and torque ripple. Second, a sequential nonlinear programming (SNP) algorithm is used for realizing the multi-objective optimizations of strong-sensitive design variables. Then, the performances of the two optimal motors are analyzed and compared with the initial permanent magnet motor in detail. Finally, two prototype motors are manufactured and tested. Both the simulation and experimental results verify the validity of the new flux-intensifying motors and the optimization method.

In this paper, a variable-saliency-ratio permanent magnet (VSR-PM) motor is designed and optimized considering driving cycles. To satisfy the demands of multi-operation conditions of EVs, a variable resistance is adopted and a new variable-saliency-ratio design concept is proposed to enhance output torque, widen speed range and lower irreversible demagnetization risk effectively. A multi-objective optimization considering driving cycles is proposed, where the design objective of saliency ratio is firstly selected and optimized with multi-objective genetic algorithm (MOGA) method. Then, the operation performances of the motor in different operation conditions are investigated in detail. Finally, a prototype motor is built and tested. Both the simulation and experimental results verify the validity of the proposed method.

In this paper, an airgap-harmonic-orientated design method is proposed, where the airgap harmonics are newly acted as the effective bridge between the three key elements of permanent magnet sources, modulators, or armature windings and the motor performances. And in the proposed design method, the airgap harmonics play couple of roles of design objectives and variables, which are not only served as the design variables for the motor performances, but also considered as the objectives for design parameters. For extensive investigation, a V-shape flux-modulated permanent-magnet (V-FMPM) motor is selected as a design example, which has a potential application for the electrical vehicles. In the optimization process, the sensitivity analysis of different airgap harmonics on the torque performance is conducted to select the leading airgap harmonics. Meanwhile, the sensitivity degrees of the design parameters on the leading harmonics are calculated to pick out the sensitive design parameters. Then, the performances of the V-FMPM motor are evaluated for validating airgap-harmonic-orientated design method. Finally, a prototype motor is built and tested. Both the theoretical analysis and experimental results verify the effectiveness and reasonability of the proposed design method and the V-FMPM motor.