Modelling and analysis of the intersecting axis permanent magnet eddy‐current coupler

Abstract

Abstract The permanent magnet eddy‐current coupler (PMEC) is a kind of non‐contact, stepless speed regulation device and has been widely used in transmissions. However, the current PMECs are coaxial and cannot achieve transmission and speed regulation in intersecting axes. An intersecting‐axis permanent magnet (PM) eddy current coupler (IPMEC), which consists of a disk‐type PM rotor and a barrel‐type conductive sheet (CS) rotor arranged with intersecting axes, is proposed. It generates eddy currents through the speed difference between the two rotors and uses the non‐contact electromagnetic force between the eddy currents and permanent magnets to transmit torque. During operation, the speed can be adjusted by altering the coupling area or air gap. A theoretical model of the IPMEC based on the equivalent magnetic circuit method is presented and verified by finite element simulation using ANSYS. Then, the effects of the pole number of the PMs, the radius of the CS rotor and the PM rotor on the performance were analysed, and the design method of the IPMEC was proposed. This study can be used to expand the application range of PMECs.

Keywords

• eddy currents
• electromagnetic coupling
• magnetic forces
• permanent magnet machines
• variable speed drives