Comparison of FPCB windings of BLDC machines with paralelly and radially magnetized rotor poles

A technological leap is occurring in slotless brushless motors. Windings made of copper wires are replaced by windings printed on a flexible PCB. This technology offers a potential of new shapes and new topologies of the windings, increasing the efficiency of the slotless brushless motor. This paper is a contribution to this new field of research, investigating deeply curved loop windings, and comparing the shapes obtained in case of radially or parallely magnetized magnets, and AD or DC current feeding.