Study of the load reduction for hydro-generator bearing by hybrid magnetic levitation

Abstract

To solve the problem of heat and friction existing in weight bearing of the hydraulic generator, a new type of magnetic levitation devices is proposed. The devices consist of electromagnetic and permanent magnetic levitation, which share together most of the hydraulic generator rotor weight to reduce axial load on thrust bearing. The permanent magnetic levitation is performed by new repulsive ring Halbach arrays. The new Halbach arrays are analyzed by using magnetic potential equations and superposition principle, and the magnetic flux density formulas are obtained. The formula results are verified by FEM. By further study of 3D model simulation analysis, it is confirmed that the new repulsive ring Halbach arrays can reach the design goal on actual working conditions.