The Influence of Second Air-Gap Length on the Performance of 10 kV, 1000 kW Permanent Magnet Synchronous Motor

2020 ◽  
Vol 14 ◽  
Author(s):  
Xianghong Cao ◽  
Yanan Xu ◽  
Junfeng Sun ◽  
Honbo Qiu

Background: The influence of the second air-gap length on the performance of permanent magnet synchronous motor is usually ignored. A comparative analysis is made of line-start high-voltage permanent magnet synchronous motor in this paper. Objective: The purpose of this paper is to analyze the influence of the second air-gap length on the motor performance. Methods: A 10kV 1000kW permanent magnet synchronous motor is taken as an example and the model is established based on the finite element calculation method when the second air-gap length is different. The influence of the second air-gap length on the phasor diagram, no-load back electrodynamic force, starting performance and steady-state operation performance are studied. Based on the finite element calculation method, the torque angle, current, power factor, external power factor and d/q-axis current of the motor are analyzed, and the change of the motor phasor diagram is obtained. The influence of the second air-gap length on the no-load back electrodynamic force is studied. Results and Conclusion: The relationship between the no-load back electrodynamic force and the no-load air-gap fundamental magnetic field is determined, and the influence mechanism of the no-load air-gap fundamental magnetic field on no-load back electrodynamic force is revealed. Furthermore, the influence of the no-load back electrodynamic force on the starting performance is studied. Finally, the influence of the second air-gap length on the 10kV 1000kW permanent magnet synchronous motor steady-state performance is obtained. Based on the above analysis, some references are given for the design of motor.

2019 ◽  
Vol 43 (4) ◽  
pp. 515-525
Author(s):  
Hongbo Qiu ◽  
Yong Zhang ◽  
Cunxiang Yang ◽  
Ran Yi

The application of an inverter is becoming more and more widespread in the surface-mounted permanent-magnet synchronous motor (SMPMSM). A large number of voltage harmonics can be generated by the inverter. The electromagnetic torque, loss, and air-gap magnetic density of the SMPMSM are affected by voltage harmonic. To analyze its influence, taking a 3 kW 1500 r/min SMPMSM as an example, a two-dimensional transient electromagnetic field model is established. The correctness of the model is verified by comparing the experimental data with the calculated data. Firstly, the finite element method is used to calculate the electromagnetic field of the SMPMSM, and the performance parameters of the SMPMSM are obtained. Based on these parameters, the influence of voltage harmonic on motor performance is analyzed quantitatively. Secondly, the influence of the voltage harmonic on the air-gap magnetic field is analyzed, and the influence degree of the time harmonic on the air-gap magnetic field is determined. At the same time, torque ripple, average torque, and loss are studied when the different harmonics orders, amplitudes, and phase angles are contained in voltage, and the variation is obtained. Finally, the variation mechanism of eddy current loss is revealed. The conclusion of this paper provides reliable theoretical guidance for improving motor performance.


2013 ◽  
Vol 313-314 ◽  
pp. 37-40
Author(s):  
Shen Bo Yu ◽  
Shen Cao ◽  
Lei Li ◽  
Feng Yi Xiao

This paper presents a method of reducing cogging torque of Permanent Magnet Synchronous Motor (PMSM) based on Finite Element Method (FEM). Cogging torque can be reduced by pole and slot number combination and the length of air gap reasonably. An investigation into the cogging torque in 4 pole, 48 slot and 6 pole, 54 slot interior-magnet machines with overlapping winding is described. The calculation results show that cogging torque can be reduced by nearly 50% by pole and slot number combination reasonably. Then influence of different length of air gap on cogging torque is also researched. Cogging torque can be weaken by increasing the length of air gap effectively, the smoothness of the motor running can be improved.


2011 ◽  
Vol 383-390 ◽  
pp. 835-839
Author(s):  
Yue Jun An ◽  
Hong Liang Wen ◽  
Wen Qiang Zhao ◽  
Guo Ming Liu ◽  
Zhao Jun Meng

In order to improve the sinusoidal level of air gap magnetic field of the traditional surface PMSM, reduce its harmonic losses and fully reflect its energy-saving advantages, this paper introduces a type of sinusoidal pole width modulation permanent magnet synchronous motor. The surface magnetic poles of the rotor iron core constitute by a number of small array magnets, which makes the air gap magnetic field more sinusoidal. Placing starting winding in remaining space between array magnets of rotor outer surface to make surface-mounted permanent magnet synchronous motor add self-starting function. The sine wave distortion rate of air gap magnetic field of sinusoidal pole width modulation structure was compared with traditional surface-mounted structure by electromagnetic field calculation and experiment. The copper starting winding and aluminum starting winding were placed in sinusoidal pole width modulation structure motor respectively, and then the paper analyzes dynamic torque and rotational speed of self-starting progress. Finally the analysis is verified by experiments.


2012 ◽  
Vol 229-231 ◽  
pp. 895-898
Author(s):  
Yue Jun An ◽  
Dong Xu Pei ◽  
Li Ping Xue ◽  
Yong Li

In order to solve the existing permanent magnet synchronous motor starting from starting performance and energy target fight between rotor and limited space of conflict. The line-start permanent magnet synchronous motor with the special structure of the disk magnet polyed magnetic type has been proposed. Motor rotor punching trough, size, and cast aluminum material can give full consideration to the requirements of line-start function in the new type of permanent magnet synchronous motor. polymer magnets which is formed from alternating magnetic yokes and permanent magnetic ring is set between the hinge and the rotor part; Interval set on the outer circle of magnetic yoke take the magnetic flux to pole. Air-gap flux density can be achieved highly by utilized to set up the starting winding after the rest of the limited space in the poly magnet structure. By finite electromagnetic field analysis software Ansoft, Three-dimensional magnetic field can be analyzed in Poly-Magnet Line-start Permanent Magnet Synchronous Motor. The result show that poly magnet structure improves the air gap magnetic field strength; Under the premise of better starting capability, it can improve the power index of motor.


2006 ◽  
Vol 126 (12) ◽  
pp. 1722-1729 ◽  
Author(s):  
Akeshi Takahashi ◽  
Haruo Koharagi ◽  
Satoshi Kikuchi ◽  
Kazumasa Ide ◽  
Kazuo Shima

Sign in / Sign up

Export Citation Format

Share Document