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In permanent-magnet synchronous motor (PMSM), the winding current consists of different orders of harmonics due to the manufacture error, deadtime, and disturbances. This article proposes a winding current harmonic suppression method for PMSM by reducing the dominant fifth- and seventh-order current ripples. First, with reference frame transformation, the fifth- and seventh-order current ripples convert to sixth-order ripples in the synchronous reference frame (SRF). Then, with further transformation, these sixth-order ripples turn to dc signals. Next, the type-II Chebyshev filter is designed to extract these dc signals. Also, the proportional–integral (PI) controller is adopted to generate the current harmonic control voltage, which is setting the dc current harmonic signals reference to be zero. Finally, the current harmonic control voltage is compensated to the voltage reference in the SRF. Both the simulation and experimental results are presented to verify the effectiveness of the proposed method.

This paper proposes a new five-phase dual-stator consequent-pole brushless hybrid excitation machine based on rotor permanent magnet (rotor-PM) for wide-speed range and high output torque application in electric vehicles (EVs). To achieve brushless hybrid excitation, this machine integrates the advantages of rotor-PM and electricity excitation, in which dual stator is adopted. The key is the consequent pole, which can construct several mutually uncoupled magnetic circuits to achieve hybrid excitation. In the proposed machine, the volume of PM is decreased but the similar output torque capability is achieved, and the flux can be regulated by excitation windings effectively. The topology and operating principle of the proposed machine are analyzed. The electromagnetic properties such as the torque waveform, the back electromotive force, and the flux-regulating capability are all investigated by using finite-element analysis. Then, the machine parameters are optimized and studied. For better heat dissipation, the mechanical design is proposed. Finally, a prototype is built; the agreement of the experimental results and the simulations shows the proposed machine can provide with high output torque, high space utilization, and good flux-regulating ability in the applications of EVs.