Investigation of a Variable Flux PMSM with Mechanical Modulators between the Rotor Poles

This work aims to investigate the characteristics and potential of a permanent magnet synchronous machine (PMSM) utilizing movable elements in the rotor core between the magnets to vary the rotor flux linkage. The geometry of the machine under investigation is presented, and the flux reduction principle is described in detail. The characteristics of the variable flux machine (VFM) is compared to a conventional PMSM with internal magnets to identify the benefits and drawbacks in terms of efficiency. An analytical approach demonstrates the dependency of the flux reduction on specific machine parameters. A mechanical stress simulation is performed to show that the machine can withstand the forces acting on it. Lastly, an option to apply the flux reduction concept to a surface-mounted permanent magnet (SPM) machine is presented.