Analytical Analysis of a Novel Flux Adjustable Permanent Magnet Eddy-Current Coupling With a Movable Stator Ring

This paper proposes a novel flux adjustable permanent magnet eddy-current coupling with a movable stator ring (MSR). The slip speed of the proposed coupling can be adjusted by shifting the MSR along the axial direction. The structural feature and operation principle of the coupling are illustrated. An analytical model based on magnetic equivalent circuit method is built to compute its electromagnetic characteristics efficiently. The dynamic process of the MSR movement is simulated by employing a variable air-gap reluctance model. The eddy-current field under asymmetric magnetic field is calculated by an improved analytical method. The electromagnetic characteristics of the coupling, such as air-gap magnetic field, eddy-current, and torque-slip speed characteristics, are analytically investigated. The analytical results are verified with the results obtained by the 3-D finite-element method.