[Objective] Aiming at the issues of high permanent magnet cost
excessive air-gap magnetic field harmonics
and poor high-temperature demagnetization resistance in rare-earth permanent magnet motors for scraper conveyors
this paper proposes a hybrid-pole low-speed permanent magnet synchronous motor (PMSM) excited by both ferrite and NdFeB. The design leverages the advantages of ferrite magnets
such as low cost and strong high-temperature demagnetization resistance
to address these problems. [Methods] The electromagnetic design of the PMSM was first conducted to determine its fundamental parameters. To enhance permanent magnet material utilization
five distinct rotor structures were designed and comparatively analyzed under identical magnet usage conditions
from which the configuration with optimal torque output capability was selected. Subsequently
three hybrid-pole magnetic circuit designs were developed for comparative evaluation. Finally
finite element analysis software was employed to perform comprehensive assessments of the finalized design
including electromagnetic performance analysis
temperature field verification
and high-temperature demagnetization resistance evaluation
thereby validating the effectiveness of the hybrid-pole solution. [Results] Compared with traditional rare-earth permanent magnet motors
the hybrid-pole rotor structure reduced the permanent magnet cost by 15.5% while maintaining the rated torque
decreased the torque ripple by 16.7%
and significantly enhanced the high-temperature demagnetization resistance. [Conclusion] The hybrid-pole rotor structure demonstrates remarkable effectiveness in reducing permanent magnet costs
optimizing motor performance
and improving high-temperature stability
providing reliable technical support for energy-saving
emission reduction
and reduced maintenance requirements in scraper conveyors.