Nested winding for slotless motor

A nested winding for a slotless motor, formed by inner and outer windings which are nested together and have different inner and outer diameters,

• wherein the number of the inner and outer windings is n, same-phase coils are connected in parallel or in series, and the number n of the nested inner and outer windings is equal to or greater than two,
• wherein the coils are multi-wire coils;
• the same-phase coils located in different windings are connected in series following the rule that bemf values and phases of coil sets are the same after connection, so the coil sets are connected in parallel to form one phase of winding,
• wherein the n inner and outer windings are on n layers, respectively,
• each layer of the n layers includes six coils of three-phase windings, and
• the six coils on each layer of the n layers form a loop in an end view.