Basic Research On Planar Motor Of Halbach Permanent Magnet

Planar motor is a novel two-dimensional motion device. Compared with the traditional 2-D positioning motion device, the novel one has three main strengths. The first advantage of the new type planar motor is that it has high degree of positioning accuracy. The second is that it has fast response. The last one is that it has a small energy loss due to the reduction of the transmission device. Thus, it’s very suitable for the realm that has a high requirement to precision positioning platform. The paper proposes a scheme of a planar motor which is composed of three sets of linear units, and then does a further research on it. The research contents are as follows:Firstly, the paper chooses the motor drive scheme on the basic of integrating other researchers’ experience, and then chooses the Halbach type magnet array as the mover of the motor, and the concentrated two-phase winding as the stator of the motor.Secondly, to establish the mathematical model of the motor and to select the magnetic vector potential as well as the reasonable boundary conditions. The paper analyzes the magnetic field which is produced by permanent magnet by the means of using the method of equivalent magnetization intensity. After that, it calculates the expression of the air gap magnetic induction intensity by using the equation group of the Maxwell. In this way the analytical expressions of counter electromotive force and motor thrust will be further deduced.Thirdly, doing a finite element simulation on the planar motor, and then the Maxwell 2D simulation model is established. Through the method of finite element analysis, we can study the air gap magnetic field strength of the permanent magnet. Determine each part of the planar motor size, including magnet magnetization thickness and width, thickness of the yoke plate, coil width and height, coil diameter size. In order to lay the foundation for the study of planar motor, it’s necessary to establish the Maxwell 3D simulation model and then study the uniformity of no-load air gap magnetic field as well as the no-load back EMF waveform, the characteristics of the static thrust. Moreover, it’s essential to use dq0 decoupling method for promoting the alternating current motor steady motion.Finally, the paper makes the prototype of the planar motor and the Halbach magnet array. After that, it detects the coil resistance and inductance. Then it tests the static characteristics of the motor, the planar motor thrust fluctuation and linearity. And the measurement of no-load EMF waveform is within the research as well. At last, compared to the experiment results and simulation results, verify whether the design is reasonable or not.