Topology Design And Parameter Optimization Of Axial Magnetic Bearing

Axial magnetic bearings are divided into three types: passive, active, and hybrid, commonly usedin the high speed motor field. This paper mainly discusses topological structure and optimal design ofaxial magnetic bearing.Firstly, it analyses the essence of generating levitating force of axial magnetic bearings.According to the distribution of magnetic path, axial magnetic bearings are classified topologically.And based on the equivalent magnetic path, structure design is analyzed. By discussing theadvantages and disadvantages of various structures of hybrid axial magnetic bearings, it puts forwarda new structural permanent magnetic axial magnetic bearing and a unilateral hybrid axial magneticbearing structure.Secondly, based on the core constraints of the air gap magnetic field, permanent magneticaxialmagnetic bearing and hybrid axial magnetic bearing are designed separately with the targetfunction of dynamic and static bearing capacity and stiffness of the dynamic performance of magneticbearings. Design results correspond to the performance indicators. During the design of parameters,the target of mathematical model is clearer, and the efficiency of design is improved.In addition, aiming at the limitation of the amplifier voltage and the heating of vertical motor ofunilateral hybrid axial magnetic bearing system, this paper establishes the optimal model of hybridaxial magnetic bearing from the perspective of power supply voltage and temperature rising. AndSWIF, one of the nonlinear constrained optimal algorithms of sequential weighted factor method, isapplied to optimize the parameters.Finally, performance verification experiment platform of permanent magnetic axial magneticbearing is designed based on the vertical brushless DC motor. The static magnetic bearingstiffness characteristic is tested to put forward the off-line correction method for the error ofdisplacement sensor, which verifies the effect of the permanent magnet field loss to thestiffness properties of magnetic bearing.