Optimal Design of Ferromagnetic Pole Pieces for Transmission Torque Ripple Reduction in a Magnetic-Geared Machine

Abstract

-This paper derives an effective shape of the ferromagnetic pole pieces (low-speed rotor) for the reduction of transmission torque ripple in a magnetic-geared machine based on a Box-Behnken design (BBD). In particular, using a non-linear finite element method (FEM) based on 2-D numerical analysis, we conduct a numerical investigation and analysis between independent variables (selected by the BBD) and reaction variables. In addition, we derive a regression equation for reaction variables according to the independent variables by using multiple regression analysis and analysis of variance (ANOVA). We assess the validity of the optimized design by comparing characteristics of the optimized model derived from a response surface analysis and an initial model.

Flux modulated rotating pole piece magnetic gear

“…In 2001, K. Atallah designed a high torque density MG called as the coaxial magnetic gear (CMG), where it applies the principle of magnetic flux modulation between PM and pole piece [18,19]. Based on the flux modulation technique, many CMG topologies were published [20][21][22][23][24][25][26][27][28][29][30]. CMG introduced by K. Atallah is reillustrated in Figure 2 in JMAG Application Note [31].…”

Investigating the Performance of a Fully Laminated Flux-Focusing Magnetic Gearbox

“…The authors along with Kowol [16] also recently constructed a cage rotor using laminations stacked along the azimuthal length, as shown in Figure 2(b) while this significantly reduces losses the laminations are mechanically difficult to retain in place. Kim et al proposed using circular non-magnetic cage rotor support rods in [17], Kim simulations showed this could reduce torque ripple. However, an experimental prototype was not presented.…”