Investigation of third harmonic utilization for torque performance improvement in novel H-type modular stator consequent pole machine.

In comparison with surface-mounted permanent magnet synchronous machines (SPMSM), inset permanent magnet consequent pole synchronous machine (IPMCPSM) reduce permanent magnet volume to half; however, magnetic circuit in consequent pole (CP) machines are un-balanced between iron pole and PM pole which results significant harmonics in magnetic flux density which contributes to torque ripple ( T rip ) and cogging torque ( T cog ) leading to vibration and acoustic noise. To overcome the above-mentioned shortcomings, this paper proposes a novel H-type modular stator IPMCPSM is proposed, and 3rd order harmonic shaped rotors are thoroughly investigated for average torque ( T avg ) improvement and suppression of T cog and T rip . For this purpose, sin shape, sin+3rd order harmonic, inverse cosine and inverse cosine with 3rd order harmonic are investigated. Analysis reveals that using 3rd harmonic shaped rotor, harmonic content of back-EMF is curtailed by 35.93%, intensify flux linkage up to 2.9%, increase T avg up to 10.24%, repressed T cog up to 75.27% and diminish T rip up to 73.56% when compare with initial rotor structure. [ABSTRACT FROM AUTHOR]