An efficient conformal mapping method for air-gap magnetic field analytical calculation in an eccentric magnetic harmonic gear

Compared to traditional magnetic gears, magnetic harmonic gears offer the advantage in terms of larger output torque density with a high gear ratio. An efficient conformal mapping method for predicting the radical and tangential flux density in an eccentric magnetic harmonic gear is developed. The eccentric air-gap magnetic field is calculated due to the permanent magnet of the eccentric rotor or stator acting alone, and then the air-gap magnetic field of the magnetic harmonic gear is obtained according to the superposition principle. Air-gap flux density of the analytical results are compared with the finite element analysis results, which proves the accuracy and the effectiveness of the derived expressions.

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