A Simple and efficient quasi-3D magnetic equivalent circuit for surface axial flux permanent magnet synchronous machinesHemeida, Ahmed; Lehikoinen, Antti; Rasilo, Paavo; Vansompel. Hendrik; Belahcen, AnouarIEEE transactions on industrial electronics2019 / p. 8318-8333 : ill https://doi.org/10.1109/TIE.2018.2884212