The Design And Research Of External Rotor Permanent Magnet Synchronous Motor Used As Elevator

Elevator is closely related to human beings nowadays. Motor is a vital part of theelectrical integration device, and its performance directly affects the performance of starting,braking, acceleration and deceleration of the elevator. There are many significant advantagesof the external rotor permanent magnet synchronous motor (PMAM) used as a gearlesselevator motor drive system, especially the high efficiency,, fast dynamic response, smallsize, so they are more and more widely manufactured and application.Firstly, the theory of external rotor PMAM fractional-slot double windings of shortpitch layers was analyzed, which can reduce the cogging torque. And then windingconnection scheme was designed. Two external rotor permanent magnet synchronous motorswere designed based on the PMSM design methods. Use the program to finish the motorelectromagnetic design, to get the motor design parameters, then use Ansoft to set up thefinite element models according to these parameters, consummate the design according tothe results of simulation, such as no-load leakage co-efficient. Then the motors’ no-load andrated-load performances were analyzed and simulated, to achieve the better scheme. Thenanalyze the error between the designed motor and the manufactured motor’s measuredperformance, and prove the correctness of the motor design.The air gap flux density was analyzed by MATLAB, to get the fundamental andharmonic amplitudes, showing that the3th,5th and7th harmonic are more than oth-ers. The air gap flux density of the eccentric magnet pole was studied utilizing an a-nalytic method. The expression of air gap flux density with offset in parallel magnet-ization or radial magnetization was detailed, to get the better eccentricity with the an-alytical method. According to the better eccentricity, the model was simulated whenthe eccentricity was respectively45mm,47mm,50mm,55mm, to get the harmonic a-nalysis of the air gap flux density and the optimal eccentricity, to prove the correctn-ess of the calculation. The elevator with external rotor PMSM can operate more sm-oothly after the optimization.