Abstract: An electrical machine (1) comprising: a rotatable drive shaft having a rotational axis (15); a rotor assembly (2) connected to the drive shaft, the rotor assembly 2 arranged to generate a static rotor magnetic field; a primary stator assembly (4), comprising a plurality of stator coils (5a, 5b) arranged to generate a rotating stator magnetic field for interacting with the static rotor magnetic field of the rotor assembly (2) such as to rotate the rotor assembly (2) along the rotational axis (15), and a secondary stator assembly (7) arranged to generate a static stator magnetic field; wherein the electrical machine (1) comprises a magnetic torsion spring (9) formed by the interaction of the static stator magnetic field with the static rotor magnetic field.

Abstract: A yokeless stator for an axial flux machine, comprising a housing, the housing comprising a circumferential portion and a plurality of elongated portions extending radially inwards therefrom, and a plurality of discrete stator teeth arranged within the circumferential portion, each discrete stator tooth comprising a ferromagnetic material and an electrical winding; the housing further comprising an electrically isolating filling material filling empty space inside the housing. The circumferential portion of the housing is made of a first non-ferromagnetic material and the elongated portions are made of a second non-ferromagnetic material. The housing comprises a laminated structure, which comprises at least part of the plurality of inwardly directed elongated portions.

Abstract: A yokeless stator for an axial flux machine, comprising a housing, the housing comprising a circumferential portion and a plurality of elongated portions extending radially inwards therefrom, and a plurality of discrete stator teeth arranged within the circumferential portion, each discrete stator tooth comprising a ferromagnetic material and an electrical winding; the housing further comprising an electrically isolating filling material filling empty space inside the housing. The circumferential portion of the housing is made of a first non-ferromagnetic material and the elongated portions are made of a second non-ferromagnetic material. The housing comprises a laminated structure, which comprises at least part of the plurality of inwardly directed elongated portions.

Abstract: Permanent magnet synchronous machines (100) are described having good efficiency, as well as corresponding methods for making a stator (110) or stator teeth (114) for such machines. A method for fabricating a stator (110) for an axial flux permanent magnet synchronous machine is for example described comprising obtaining several sets of substantially identical laminates (302), and stacking the sets of substantially identical laminates (302) so that a subsequent laminate has a part overlapping (304) the previous laminate and a part not overlapping (306) the previous laminate. Alternatively, a method of manufacturing a stator (110) is described wherein the method comprises obtaining a set of laminates (302) connected to each other with a thin strip (402) of material and creating a stack by folding the laminates (302) along the thin strip (402) of material.

Abstract: Permanent magnet synchronous machines (100) are described having good efficiency, as well as corresponding methods for making a stator (110) or stator teeth (114) for such machines. A method for fabricating a stator (110) for an axial flux permanent magnet synchronous machine is for example described comprising obtaining several sets of substantially identical laminates (302), and stacking the sets of substantially identical laminates (302) so that a subsequent laminate has a part overlapping (304) the previous laminate and a part not overlapping (306) the previous laminate. Alternatively, a method of manufacturing a stator (110) is described wherein the method comprises obtaining a set of laminates (302) connected to each other with a thin strip (402) of material and creating a stack by folding the laminates (302) along the thin strip (402) of material.