The Design And Research Of High Performance And Low Cost Permanent Magnet Motor For Elevator

Elevator as an important part of high rise building, bring more convenient andshortcut to people’s life. Traditional traction machine for elevator mostly use inductionmotor with reduction box as the driving system of elevator. In recent years, with thecontinuous development of permanent magnet synchronous motor (PMSM) with theadvantages of small volume, light weight, high efficiency, good dynamic performance, andenergy saving, induction motor with reduction box has been gradually replaced,synchronous motor with high performances become the preference of elevator’s drivingmotor. The design and research of high performance PMSM for elevator is the key point toimprove the performances of elevator. In this paper, PMSM for elevator with low speedand large torque of32kW and255revolutions per minute is studied, and6schemes ofdifferent pole-slot combinations are designed.Firstly, PMSM schemes of five different pole-slot combinations are designed, theeddy current loss in permanent magnet of the five schemes calculated by3D time-steppingFEM, and the influence of harmonic frequency to the eddy current loss in permanentmagnet be analyzed to provide the application range of different matches of poles and slotsfor PMSM with low speed and large torque. In allusion to the motor of20-pole and72-slot,the influence of segmentation to the eddy current loss in permanent magnet is analyzed.Secondly, a PMSM of44-pole and48-slot designed, its eddy current loss inpermanent magnet calculated by3D FEM. The influence of air gap length, slot width andpermanent magnet chamfering to the eddy current loss in permanent magnet are analyzed.Then, optimum structure design of6different matches of poles and slots processed.Through the comparisons of performances and costs, matches of poles and slots for finalscheme chosen20-pole and72-slot.Finally, for the scheme of20-pole and72-slot, the cost of motor’s efficient materialbrought down through decrease of air gap length and magnetizing thickness of permanent magnet while maintaining the performances of motor. And the largest demagnetizingworking point of permanent magnet computed to ensure the safety performance of themotor, and realize the ultimate design of cost-effective elevator motor.