Optimal Design and Analysis of the Novel Low Cogging Torque Axial Flux-Switching Permanent-Magnet Motor

Abstract

The axial field flux-switching permanent-magnet machine (AFFSPM) is one of the most efficient machines which is appropriate for high torque and low-speed direct-drive applications. In this paper, the novel axial field flux switching machine with sandwiched permanent magnet (AFFSSPM) is proposed in order to increase torque density and decrease cogging torque. The proposed model equipped with an advanced phase-group concentrated-coil winding to obtain a unity displacement winding factor. Two three-phase 6-stator-slot (S)/10-rotor-pole (P) and 12(S)/19(P) configurations of the proposed model are investigated. Some specific design issues, including the sandwiching pole angle, the stator tooth angle, and the rotor pole angle have been optimized to obtain the maximum torque density and minimum cogging torque by artificial neural network and non-sorting genetic algorithm II. Moreover, the static electromagnetic characteristics are investigated. Compared with the conventional AFFSPM and 6(S)/10(P) AFFSSPM, the 12(S)/19(P) proposed machine shows higher torque density, lower cogging torque, and higher level of fault-tolerant capability. In order to improve the dynamic performance of the AFFSSPM motor, a space vector modulation-direct torque and flux control (SVM-DTFC) scheme is proposed. The AFFSSPM motor exhibits excellent dynamic performance with proposed scheme.

Keywords:

• flux-switching
• axial field
• sandwiched permanent magnet
• 3-D FEM
• artificial neural network
• non-sorting genetic algorithm II
• space vector modulation
• direct torque control

Additional information

Notes on contributors

Javad Rahmani Fard

Javad Rahmani Fard received the B.S. degree from Shahed University, Tehran, Iran, in 2009, and the M.S. degree from K.N. Toosi University of Technology, Tehran, Iran, in 2012, both in electrical engineering. He is currently working toward the Ph.D. degree in electrical engineering at the K.N. Toosi University of Technology, Tehran. His research interests include the numerical modeling of electrical machines, fault tolerant drives, and power distribution systems.

Mohammad Ardebili

Mohammad Ardebili received the M.S. degree in 1976 from the University of Tabriz, Tabriz, Iran, and the Ph.D. degree from the University of Wales, Cardiff, U.K., in 1991, both in electrical engineering. He is currently an Associate Professor and the Head of the Electrical Machines and Drives Laboratory (EMDL), Electrical Engineering Department, K.N. Toosi University of Technology, Tehran, Iran. His research interests include electrical machines and drives, magnetic materials, design and modeling of permanent magnet machines, and wind generators.