Suspension Force Analysis on Novel Heteropolar Four Degrees of Freedom Hybrid Magnetic Bearing

In this paper, a novel four-pole heteropolar four degrees of freedom (4-DOF) hybrid magnetic bearing (HMB) is researched. It consists of a pair of independent X stator cores and Y stator cores, which greatly eliminates the coupling of the magnetic circuit in the X and Y directions, and reduces the complexity of the control system. Firstly, the configuration of the proposed heteropolar HMB is introduced. Secondly, the mathematical models of radial suspension forces are deduced. Then, the main parameters of the HMB are designed. Finally, the magnetic circuit and force-current relationships are calculated by software MagNet 3D. The research results have shown that the structure is reasonable and the magnetic circuit is correct. Especially, there is no coupling between the suspension forces.