Exterior-rotor Permanent Magnet Research Articles

Computational Technologies for Low-Frequency Torque Ripple Suppression in Exterior-Rotor Permanent Magnet Motors

Exterior-rotor permanent magnet direct-drive motors (ERPMDDMs), which have a simple structure and high energy efficiency, can achieve high torque output at low speed. Because of the superior performance, ERPMDDMs have been widely used in low-speed and high-torque (LSHT) mechanical equipment. The stability of the LSHT drive of ERPMDDMs directly affects the reliability of the equipment, which is thoroughly studied in this work by taking 250 kW ERPMDDMs as an example. The influence of different pole-to-slot ratios and pole-arc coefficients on the cogging torque is analyzed by the electromagnetic field calculation and analysis software Ansoft, and several parameters are optimized to reduce the torque ripple in energized motors and ensure the stability and reliability of the equipment.

Exterior Rotor Permanent Magnet Brushless Dc Motor through Numerical Method of the Electromagnetic for Torque Improvement

In this paper, Numerical method based Exterior Rotor Permanent Magnet Brushless Direct Current (ERPMBLDC) is proposed aiming to integrate its torque. The ERPMBLDC Machine construction and principle of operation will be designed using Finite Element Method Magnetic 4.2(FEMM4.2) software. Then the flux pattern distribution based on the numerical method of ERPMBLDC motor estimation derived. The proposed motor parameters such as flux pattern, phase angles for maximum torque and torque were analyzed and compared by simulation and by experimental results.

A Novel High Energy Density Double Salient Exterior Rotor Permanent Magnet Machine

In this paper, a double salient exterior rotor permanent magnet machine is proposed and analyzed. This machine introduces the use of permanent magnet (PM) into a switched reluctance machine and has the same envelope as that of Toyota Prius third-generation (P3G) 60 kW interior PM synchronous machine (IPMSM). Simulation results show that the continuous torque and peak torque of the proposed machine are 97% and 30.4% more than that of P3G IPMSM under the same current density.

High-performance permanent magnet brushless motors with balanced concentrated windings and similar slot and pole numbers

The paper presents a comparison between the performances of exterior-rotor permanent magnet brushless motors with distributed windings and the performances of exterior-rotor permanent magnet brushless motors with concentrated windings. Finite element method analysis is employed to determine the performance of each motor. It is shown that motors with concentrated windings and similar slot and pole numbers exhibit similar or better performances than motors with distributed windings for brushless AC (BLAC) operation mode and brushless DC (BLDC) operation mode as well.