Calculation and simulation of back electromotive force and cogging torque for permanent magnet BLDC motor;

Factors influencing noise of the motor systems such as cogging torque, HALL signal errors and armature magnetic field are analyzed.

The effects of stator and rotor eccentricity on the magnetic field distributions,cogging torque and unbalanced force were calculated in this paper by using finite element method(FEM).

The cogging torque of permanent magnet synchronous motor is harmful to driving systems.

The magnet torque and cogging torque equations are also developed for threephase permanent magnet inductor synchronous motor(PMISM).

2D finite element method was used to analyze the starting period, the pulling into period and cogging torque of line-start permanent magnetic synchronous motor, contrasting with the experiment result, the calculation had good precision.

In single-phase brushless DC motors with high magnetic load, the typical asymmetric air-gap structure will lead to high cogging torque peaks, which will distort the torque envelope together with the high current peaks commonly found.

But this double salient structure also causes that the cogging torque in FRM is great,which can influence the smooth of t.

The effects of the Axial double cut iso-thick tile shape magnet to the position torque of the tooth-tough armature permanent-magnet motor and the induction EMF wave of the armature are analyzed in this paper by using the principle of 3 dimensional air-gap magnetic density wave of permanent-magnet motor.

Using the finite element method(FEM),the no load magnetic field in permanent magnetic micro servo-motor is calculated,therefrom the position torque can be difined.

Taking the product/service attribute system as a foundation, the article utilizes two-factor theory expanded and means-end theory to establish the product/service positional matrix which is based on customers cognition object and customers satisfaction, so as to explore the new method of positioning product/service.