Analysis for design optimisation of double PM-rotor radial flux eddy current couplers

In this study a semi-analytical calculation method for obtaining 3D solutions for the torque of radial flux permanent magnet eddy current couplers is presented. In this way the use of computationally expensive transient 3D finite element solutions is avoided, which is very important when it comes to the design optimisation of these machines. The proposed analytical method takes the effect of flux density harmonics into account. The 3D end-effects are taken into account by using Russell´s coefficient. The accuracy of the proposed semi-analytical calculation method is evaluated against extreme variation of machine dimensions. It is shown that this fast calculation method can be used with great accuracy in the design optimisation of these couplers.