Modeling and Design of a Dual-Stator Low-Speed High-Torque Permanent Magnet Drive Machine for the Ball Mill Application

The dual-stator permanent magnet (PM) machine has the advantages of high torque density, high efficiency, and compact size, which makes it suitable for low-speed high-torque applications. A dual-stator low-speed high-torque permanent magnet drive machine (DLHPMDM) is discussed and studied in this paper, which is applied to the ball mill application. First, in order to meet the requirements of high efficiency and high reliability, a DLHPMDM with the inner and outer windings connected in parallel is obtained through the designs carried out in terms of the magnetic circuit structure, structural size, and the pole-slot number combination. However, for the DLHPMDM with the inner and outer windings connected in parallel, the power allocation between the inner and outer machines is a critical problem that needs to be accurately analyzed, and the circulating current between the two sets of windings is also a particular issue that merit attention. Therefore, a new modeling method is proposed for the DLHPMDM to solve such cases more accurately. The proposed new method combines the advantages of the rapidity of the finite element analysis (FEA) with current excitations and the accuracy of the FEA with voltage excitations. Finally, a prototype of the DLHPMDM is manufactured and tested. The feasibility of the design theory and the validity of the proposed modeling method is verified by both the tested and simulated results.(c) 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.