Effect of design variables on irreversible permanent magnet demagnetization in flux-reversal machine

The large demagnetizing currents in flux-reversal machine (FRM) are generated by the short-circuited of stator windings and the fault of a drive circuit. So, irreversible magnet demagnetization occurs due to the external demagnetizing field by these currents. In this paper, we deal with the effect of design variables on irreversible magnet demagnetization in the FRM using two-dimensional finite-element method (2D FEM). The nonlinear analysis of a permanent magnet is added to 2D FEM to consider irreversible demagnetization. As a result, it is shown that magnet thickness and rotor teeth width are the most important geometrical dimensions of the FRM in terms of irreversible magnet demagnetization.