Exact Analytical Magnetic Field Analysis, Optimization Design and Realization of an Eccentric Magnetic Harmonic Gear

The eccentric magnetic harmonic gear (EMHG) has a high efficiency and high gear ratio capability for large torque transmission. The air gap magnetic field can be calculated using an exact analytical model. The analytical approach is based on the theoretically accurate hyperbolic cotangent transformation method. The relative permeance function, which is derived from the impact of rotor eccentricity, can be used to find the eccentric air gap magnetic field solution. The proposed analytical approach is employed as the basis for a genetic algorithm that is used to develop and optimize the EMHG. The analytical results are in good agreement with the finite element method results, which verifies the correctness and validity of the proposed analytical model. The experimental measurements on the dual-stage EMHG confirm the validity of the analytical prediction.