Performance analysis and optimal design of dual permanent magnet motors for EV drive

Pao Yue-kong Library Electronic Theses Database

Performance analysis and optimal design of dual permanent magnet motors for EV drive


Author: Ma, Yue
Title: Performance analysis and optimal design of dual permanent magnet motors for EV drive
Degree: M.Sc.
Year: 2016
Subject: Permanent magnet motors.
Electric vehicles.
Hong Kong Polytechnic University -- Dissertations
Department: Faculty of Engineering
Pages: ix, 64 pages : color illustrations
Language: English
InnoPac Record:
Abstract: Permanent magnet synchronous motors (PMSMs) are more widely used in the electric vehicles (EVs) as a new motor-driving technology. PMSMs with high electromagnetic torque and high efficiency ensure a good performance in EVs application. In this thesis, a conventional interior permanent magnet synchronous motor (IPMSM) and two new designed dual-permanent magnet synchronous motors have been simulated, analyzed and compared. All the PMSMs are operated in 1000rmp rated rotating speed and made the induced voltage to be smaller than 60V. At the same time, the torque should reach to 120N{168}m. According to other people's research results, an IPMSM is used as a basic model. The IPMSM uses the distributed windings in the stator and "V" shape permanent magnets (PMs) inserted in rotor in order to get higher torque and efficiency. Three-phase sinusoidal current as excitation inserts in the distributed windings. After finite element analysis (FEA), the torque value, core loss value and efficiency can be received or calculated. There are also two new PMSM designs in this thesis. Both of them have two rotors and two stators. Each motor also can be seen that two PMSMs combines together to get a new motor. More PMs are used in the new designs. Using PMs is aimed to get magnetic field without external excitations nor energy consumption. The first design is relatively simpler than the second one. It has PMs in outer rotor, outer stator and inner stator. The number of stator pole-pairs and rotor pole-pairs are 9 and 13 respectively. The magnet flux direction has been selected from four schemes. Concentrated windings have been inserted in three-phase sinusoidal current as an excitation method. After FEA, some parameters which reflect the motor performance can be obtained, such as torque, efficiency and core loss.
The second design is more complicated than the first design. The stator pole-pair number is 16 and rotor pole-pair number is 33. All the stators and rotors are inserted with PMs. It also has complex slots in the outer stator. There are four schemes for PMs flux direction. The scheme which has the highest torque has been used in the final design. The torque and core loss are also obtained by FEA. According to the result from FEA, the efficiency can be calculated as well. The effectiveness of genetic algorithm (GA) which is used to do the optimization process has been proved in this thesis. A function which has the maximum value is regarded as objective function. The GA process has been used to optimize the result of function in the range of independent variables. The values of the final objective function and independent variables have been analyzed. Finally, the process effectiveness has been proved. It is suitable to solve the global optimization problem. In the final part, each motor has been optimized and self-compared. After optimization, the total performance of each motor has been improved. The improving degrees are different of different motors. The main reference values are torque, efficiency and volume of each motor. Finally, three optimized motors have been compared together. The second design has the best performance in torque, efficiency, volume even core loss.

Files in this item

Files Size Format
b29527636.pdf 4.135Mb PDF
Copyright Undertaking
As a bona fide Library user, I declare that:
  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.


Quick Search


More Information