An electric motor apparatus comprising: a stator component and a rotor component rotationally mounted coaxially with and within said stator component; said stator component and said rotor component each comprising windings (24; 54) configured to generate an electromagnetic field from an electric current; said electric motor further comprising an intermediate screening component rotationally mounted between said stator component and said rotor component and configured to provide at least some magnetic screening between said rotor component and said stator component, wherein said intermediate screening component comprises a plurality of protrusions extending from said intermediate screening component on both said inner and outer surfaces, wherein said inner and said outer surface comprise a same number of said plurality of protrusions, said plurality of protrusions on said inner surface being offset compared to said plurality of protrusions on said outer surface, such that a protrusion on said inner surface is not formed at a same circumferential position as a protrusion on said outer surface; said protrusions are formed by said inner and outer surfaces being undulating surfaces, said undulating surfaces undulating at a substantially same rate and same direction such that a thickness of said intermediate screening component is substantially constant around the circumference; said intermediate screening component comprising at least some magnetically active sections configured such that changing magnetic fields generated by changing electric currents in said windings on either said rotor component or said stator component generate a force on said magnetically active sections causing said intermediate screening component to rotate; the electric motor further comprising control circuitry (26; 56) for independently controlling power supplied to said windings on said rotor component and said stator component in dependence upon a desired output rotational speed. a stator component and a rotor component rotationally mounted coaxially with and within said stator component; said stator component and said rotor component each comprising windings (24; 54) configured to generate an electromagnetic field from an electric current; said electric motor further comprising an intermediate screening component rotationally mounted between said stator component and said rotor component and configured to provide at least some magnetic screening between said rotor component and said stator component, wherein said intermediate screening component comprises a plurality of protrusions extending from said intermediate screening component on both said inner and outer surfaces, wherein said inner and said outer surface comprise a same number of said plurality of protrusions, said plurality of protrusions on said inner surface being offset compared to said plurality of protrusions on said outer surface, such that a protrusion on said inner surface is not formed at a same circumferential position as a protrusion on said outer surface; said protrusions are formed by said inner and outer surfaces being undulating surfaces, said undulating surfaces undulating at a substantially same rate and same direction such that a thickness of said intermediate screening component is substantially constant around the circumference; said intermediate screening component comprising at least some magnetically active sections configured such that changing magnetic fields generated by changing electric currents in said windings on either said rotor component or said stator component generate a force on said magnetically active sections causing said intermediate screening component to rotate; the electric motor further comprising control circuitry (26; 56) for independently controlling power supplied to said windings on said rotor component and said stator component in dependence upon a desired output rotational speed.