To make the motor perform better during operation, a conical outer rotor structure is proposed based on the traditional outer rotor permanent magnet vernier motor (PMVM) structure. The electromagnetic characteristics of PMVM and COR-PMVM are compared and analyzed. The parameters of COR-PMVM are optimized, and the motor's temperature rise is simulated and analyzed by magneto-thermal coupling. Simulation results demonstrate a 39.3% increase in electromagnetic torque of the engine, and a 33.3% reduction in torque ripple. The stator and winding can reach a temperature of 101.72 °C, whereas the rotor and permanent magnet remain cooler at 70 °C. Lastly, a temperature rise experiment is conducted on the permanent magnet motor to validate the precision of the magnetothermal coupling analysis method.