Genjiro Wakui

Steady-state performance analysis of permanent magnet synchronous motors including space harmonics

This paper describes the method for the analysis to obtain steady-state currents and torques of permanent magnet synchronous motors including space harmonics. A time-stepping finite element technique including the rotor movement is proposed, where both terminal voltage and load angle are given as the known values. In simulating the rotor movement, the suitable rotation step to take account of the effects of space harmonics, is determined. The agreement between calculated and measured results of the synchronous performance in an experimental motor is good. >

Hysteresis motor using magnetically anisotropic Fe-Cr-Co magnet

For the rotor ring of the hysteresis motor, semihard Alnico magnets have been almost applied until now. However, the hysteresis motor using Alnico magnets has several disadvantages. In order to improve the disadvantages of conventional hysteresis motors, the Fe-Cr-Co magnet steel with magnetic anisotropy is applied for hysteresis rotor ring. Magnetic anisotropy is used to cause large reluctance torque and large hysteresis torque at synchronous pull out. It is made clear from experimental results that these hysteresis motors have large output, high efficiency, and high power factor, to add the reluctance torque to hysteresis torque effectively.

Radial flux type hysteresis motor with reaction torque--Numerical analysis of hysteresis motor using finite element method

This paper describes a new form of the radial flux type hysteresis motor having large output, high efficiency, and high power factor. The rotor ring of the machine is made of Fe-Cr-Co magnet steel and has magnetic anisotropy and slits. In order to analyze motor performance at synchronous speed and starting, the finite-element method is used. In this paper, magnetic hysteresis is considered by Using complex permeability. Predicted and measured values of motor performance characteristics agree well. Finally, the relation between dimensional ratio of slits and motor performance is described quantitatively.

Analysis of a Hysteresis Motor on Asynchronous Speed Using Complex Permeability

This paper deals with a method for determining the complex permeability in analysis of hysteresis motors. The method assumes that the magnetic intensity distribution is sinusoidal in the direction of rotation. Analysis of the asynchronous speed of a hysteresis motor is then performed for cylindrical coordinates, using modified Bessel functions. The results of calculations are in good agreement with experimental results, confirming the effectiveness of the proposed model and method for determining the complex permeability.