Design and Control of A New Compound Double-Rotor Electric Machine for Hybrid Propulsion System

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Original languageEnglish
Pages (from-to)3283-3296
Journal / PublicationIEEE Transactions on Power Electronics
Issue number3
Online published10 Sept 2021
Publication statusPublished - Mar 2022


In this paper, a new compound consequent-pole double-rotor electric machine (CCPDRM) is proposed for hybrid propulsion system (HPS) application. First, the operating principle and harmonic components in CCPDRMs are elucidated. The winding factor theory for conventional permanent-magnet (PM) electric machine is further extended and applied in CCPDRMs. Then, this improved theory is adopted to investigate the structure and winding scheme requirement of the proposed CCPDRMs. In addition, the control strategy for the proposed CCPDRM is established. By utilizing a parameter sweep method, the variation trends of CCPDRMs torque density with respect to various geometrical parameters are revealed. Based on this, the structure of CCPDRMs is optimized to acquire the better electromagnetic performance. Next, the proposed CCPDRM is compared with a conventional compound bipolar double-rotor electric machine (CBDRM). And it is found that the improved topology has a similar torque density but a much higher PM utilization factor and a lower PM demagnetization risk when compared with CBDRMs. Finally, a prototype is manufactured and tested in different operating modes. Furthermore, various mode-switching processes are performed to emulate the practical driving cycle of a hybrid transportation. Both steady-state and dynamic mode- switching experimental results prove the effectiveness of CCPDRMs.

Research Area(s)

  • consequent pole, Electric machines, Gears, Harmonic analysis, hybrid propulsion, mode switching, Modulation, Permanent magnet machine, Rotors, Torque, utilization factor, winding scheme, Windings