Design of a Dual-Permanent-Magnet Vernier Machine to Replace Conventional Surface-Mounted Permanent Magnet Motor for Direct-Drive Industrial Turbine Application

Abstract

Surface-mounted permanent magnet motors (SMPMMs) have been widely used in industrial fields. However, when it comes to direct-drive low-speed large-torque fields, SMPMMs have several problems, such as lower slot filling factor, complicated fabrication, low efficiency, and bulky size. Recently, dual-permanent-magnet Vernier motors (DPMVMs) have been investigated due to their high torque density for low-speed direct-drive applications. However, so far, there is little research that demonstrates the application of the DPMVM for real industrial fields and quantitatively compares the performances of the DPMVM and the SMPMM. This paper studies the application of a DPMVM to the direct-drive industrial turbine as a replacement for conventional SMPMM. Rectangular and trapezoidal PMs are first applied to DPMVM in this paper. The performances of the DPMVM are quantitively compared with two typical SMPMMs. One is the design that has the same stator slots as the DPMVM, while the other has the same rotor pole pairs as the DPMVM. Economic costs are considered to form a thorough comparison between DPMVM and SMPMMs. It is revealed that with rectangular and trapezoidal PMs adopted in the DPMVM, the cost of PMs is significantly reduced with little sacrifice of performance. The efficiency of DPMVM is around 12% higher, and the material cost is reduced by 6.87% compared with the SMPMN.

Electromagnetic Characteristics of Dual-Air-Gap Surface Permanent Magnet Synchronous Motor

“…The finite element method (FEM) is frequently used to analyze complex motor structures, as it has been demonstrated that the simulation results obtained by using FEM are highly consistent with experimental results, indicating the accuracy and reliability of FEM analysis [23][24][25].…”

Design and Analysis of Five-Phase Fault-Tolerant Vernier Permanent Magnet Machines for Direct-Drive Occasions

“…Permanent magnet machines (PMM) can be used as power-generating or power-driven machines, which adopt permanent magnet (PM) instead of excitation winding. Vernier PMM (VPMM) [1]- [3] possesses vernier modulation effect. In recent years, VPMMs have received wide attention due to their simple constructions and high torque densities.…”

Magnetic Screen Effects on Torque Ripple and Efficiency of Dual Air-Gap Surface Permanent Magnet Synchronous Motor

“…In general, researchers aim to reduce magnet volume and increase the amplitude of air-gap flux density [23]. To achieve these goals, Halbach-array magnets placed in the slot opening have been introduced in DAG-PMSMs, resulting in a 43% improvement in torque density compared to conventional single air-gap PMSMs [24,25]. Other topologies for DAG-PMSMs have also been proposed to achieve high torque density compared to single air-gap machines [26][27][28].…”