The starting torque of a single-phase permanent magnet brushless dc motor is investigated, for both radial and parallel magnetization. Finite element analysis is used to assess the relative merits of alternative methods of introducing the required airgap asymmetry, viz. tapered airgap, stepped airgap, asymmetric airgap, and slotted teeth. The predicted results are validated experimentally.

A new permanent magnet design for axial flux interior permanent magnet (AFIPM) motor is described in this paper. Poleshoes are traditionally used to produce sinusoidal flux linkage and sinusoidal EMF especially in the case of radial flux synchronous machines. Poleshoes are not a practical solution in the case of axial flux PM machine. The use of poleshoes in the production of sinusoidal back EM...

The Permanent Magnet Brushless DC (BLDC) motor offers higher efficiency, low maintenance, reduced weight and compact construction. For many industrial applications, the BLDC motor is increasingly being used. This paper presents a new sensorless drive scheme for BLDC motor based on the back EMF difference. The commutation point of the drive is determined by detecting the Zero Crossing Point (ZCP...

In this paper a brushless permanent magnet motor is designed considering minimum thrust ripple and maximum thrust density (the ratio of the thrust to permanent magnet volumes). Particle Swarm Optimization (PSO) is used as optimization method. Finite element analysis (FEA) is carried out base on the optimized and conventional geometric dimensions of the motor. The results of the FEA deal to ...

To promote energy saving, we developed a high efficiency brushless DC motor with a new manufacturing method of a stator for compressors. This motor consists of a concentrated winding stator and an interior permanent magnet rotor. The stator has the core structure that we call “a joint-lapped core”. The joint-lapped core is able to open and bend in reverse. While winding the coil, the joint-lapp...

axial flux permanent magnet (afpm) machines are attractive candidates for electric vehicles (evs) applications due to their axial compact structure, high efficiency, high power and torque density. this paper presents general design characteristics of afpm machines. moreover, torque density of the machine which is selected as main objective function, is enhanced by using genetic algorithm (ga) a...

A brushless DC motor with integrated drive circuit for air management system is presented. Using magnetic equivalent circuit model a basic design of the motor is determined, and specific configurations are inspected thanks to finite element analysis. In order to reduce an unbalanced magnetic force in an axial direction, induced forces between a stator core and a permanent magnet are calculated ...

The application of flux-observer-based sensorless control to permanent-magnet brushless ac motor drives is described. Current methods of speed estimation are assessed, both theoretically and experimentally, and an improved method, which combines the best features of methods in which speed is derived from the differential of rotor position and from the ratio of the electromotive force to excitat...