Electromagnetic performance comparison of 18-slot/26-pole and 18-slot/10-pole fractional slot permanent magnet surface-mounted machines

This paper discusses about winding arrangement of fractional slot of a new type hollow rotor Brushless Direct Current (BLDC) motor. Hollow rotor has higher performance compared to other BLDC motor because it minimizes the unused flux below permanent magnet and maximize torque produce by the motor. It’s also known that 8 pole motor is favorite used in industrial because it has an optimum space of permanent magnet for a smaller motor size. The number of pole will affect the maximum speed of the rotor. Thus, the objective of this research is to investigate the best winding arrangement for 8 pole of hollow rotor that could produce the highest electromagnetic performance. At starts, four combinations of slot number and coil sizes had been selected. Structural comparison in term of coil vector and winding arrangement is studied. Finite Element Method (FEM) had been used to simulate the parameters such as backemf and torque waveforms. It was convinced that 9 slot 8 pole with 0.6 size of coil produces the best performance. The confirmed model had been fabricated and measured. Both results from FEM and measurement are compared in term of backemf and torque where percentage differences are 7.4 % and 8 %, respectively. As conclusion, this research shows the fundamental of winding arrangement of fractional slot of motor especially 8 pole motor.

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Electromagnetic Performance of an 18-Slot/10-Pole Fractional-Slot Surface-Mounted Permanent-Magnet Machine

IEEE Transactions on Industry Applications ◽

10.1109/tia.2014.2316362 ◽

2014 ◽

Vol 50 (6) ◽

pp. 3685-3696 ◽

Cited By ~ 26

Author(s):

K. Wang ◽

Z. Q. Zhu ◽

Grzegorz Ombach ◽

M. Koch ◽

Sunny Zhang ◽

...

Keyword(s):

Permanent Magnet ◽

Permanent Magnet Machine ◽

Electromagnetic Performance ◽

Fractional Slot

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Influence of unbalanced magnetic force on shaft deflection in permanent magnet synchronous motor with fractional slot concentrated windings

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209466 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 1461-1468

Author(s):

Ting Dong ◽

Juyan Huang ◽

Bing Peng ◽

Ling Jian

Keyword(s):

Permanent Magnet ◽

Magnetic Force ◽

Permanent Magnet Synchronous Motor ◽

Operational Reliability ◽

Topology Structure ◽

Permanent Magnet Synchronous Motors ◽

Synchronous Motors ◽

Shaft Deflection ◽

Large Length ◽

Fractional Slot

The calculation accuracy of unbalanced magnetic forces (UMF) is very important to the design of rotor length, because it will effect the shaft deflection. But in some permanent magnet synchronous motors (PMSMs) with fractional slot concentrated windings (FSCW), the UMF caused by asymmetrical stator topology structure is not considered in the existing deflection calculation, which is very fatal for the operational reliability, especially for the PMSMs with the large length-diameter ratio, such as submersible PMSMs. Therefore, the part of UMF in the asymmetrical stator topology structure PMSMs caused by the choice of pole-slot combinations is analysized in this paper, and a more accurate rotor deflection calculation method is also proposed.

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