Design and Control of a Novel Multi-Degree-of-Freedom Spherical Induction Motor

Abstract

To realize the omni-directional steering function of urban micro electric vehicle and avoid the defects of traditional multi-degree-of-freedom (multi-DOF) drive, a multi-DOF spherical induction motor (SIM) as hub motor is presented, which is used to replace the conventional wheel and steering system to drive vehicles directly. SIM is mainly composed of three arc-shaped stators and one spherical rotor. And torque is directly output from the surface of the spherical rotor. The structure parameters of SIM are determined based on the design methodology of linear induction motor (LIM), and a finite element model (FEM) is established. Meanwhile, the field-oriented control (FOC) system of SIM is designed, and a multiple physics field co-simulation platform is constituted. By electromagnetic transient simulation and co-simulation, the effectiveness of structure parameters and FOC system are verified systematically. To realize the multi-dimension drive of SIM, the torque model is analyzed, and a multi-DOF drive control strategy is proposed, which is realized by mathematical modeling. The results indicate that SIM can achieve two rotational DOF drive without the angle limitation, and the control system has appropriate dynamic and tracking performances. The design scheme and control strategy proposed are reasonable.

Keywords:

• electric vehicle
• multi-degree-of-freedom (multi-DOF)
• spherical induction motor (SIM)
• linear induction motor (LIM)
• motor control
• motor design

Additional information

Funding

This work is supported by National Natural Science Foundation of China (Grant No. 52275051), and the Science and Technology Research Key Program of Chongqing Municipal Education Commission (Grant No. KJZD-K202000701), and Key Projects of Technological Innovation and Application Development of Chongqing (Grant No. cstc2019jscx-fxydX0028), and the Open Project Found of Chongqing Key Laboratory of Green Aviation Energy and Power (Grant No. GATRI2021F01001A).

Notes on contributors

Zhentao Ding

Zhentao Ding received the M.S. degree in vehicle engineering, Chongqing Jiaotong University, Chongqing, China, in 2021. He is currently pursuing the Ph.D. degree in traffic and transportation with the State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu, China. His current research interests include linear motor technology and magnetic levitation technology.

Tao Deng

Tao Deng received the Ph.D. in vehicle engineering, Chongqing University, Chongqing, China, in 2010. He is currently a Full Professor with the School of Aeronautics, Green Aerotechnics Research Institute, Chongqing Jiaotong University, Chongqing, China, and Chongqing Key Laboratory of Green Aviation Energy and Power, Chongqing, China. His research interests include electromechanical composite transmission, new energy power system, and intelligent aircraft.

Zhenhua Su

Zhenhua Su received the M.S. degree in vehicle engineering, Chongqing Jiaotong University, Chongqing, China, in 2020. He is currently pursuing the Ph.D. degree in vehicle operation engineering with the State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu, China. His current research interests include electrodynamic suspension technology and linear motor technology.

Changjun Wu

Changjun Wu received the M.S. degree in vehicle engineering, Chongqing Jiaotong University, Chongqing, China, in 2022. His research interests include mechanism study of thermal runaway, battery thermal safety and thermal design.

Yanli Yin

Yanli Yin received the Ph.D. degree in mechanical engineering, Chongqing University, Chongqing, China, in 2011. She is currently a lecturer with the School of Mechatronics and Vehicle Engineering, Chongqing Jiaotong University, Chongqing, China. Her research interests include vehicle power transmission and integrated control, hybrid and electric vehicle control, and new energy vehicle theory and application research.