A double-stator PM machine comprising: an outer stator comprising an outer three-phase winding on an outer core, configured to generate an outer electromagnetic field dependent on an outer three-phase supply current (Io) supplied to the outer stator; an inner stator positioned concentrically inside of the outer stator, the inner stator comprising an inner three-phase winding on an inner core, configured to generate an inner electromagnetic field dependent on an inner three-phase supply current (Ii) supplied to the inner stator; a permanent magnet, PM, rotor configured to be rotated by the outer and inner electromagnetic fields in a gap formed between the outer and inner stators; and a control arrangement configured to control the outer and inner supply currents (Io, Ii), respectively; wherein there is a relative mechanical shift corresponding to an electrical angle of 30° between the outer and inner stators; wherein there is an electrical connection between a neutral point (No) of the outer stator and a neutral point (Ni) of the inner stator; wherein the control arrangement is configured to control the outer and inner supply currents (Io, Ii) such that there is a relative angle shift (Δθ) of 30° between the outer and inner supply currents, corresponding to the relative mechanical shift, and such that a third order current harmonic component (Io3, Ii3) is circulated between the outer and inner stators; wherein the control arrangement comprises an outer power electronic converter configured to output the outer supply current (Io) based on outer voltage references (Vabc ∗ o), and an inner power electronic converter configured to output the inner supply current (Ii) based on inner voltage references (Vabc ∗ i); wherein the control arrangement comprises a current controller configured to output the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) based on at least one operation reference (P ∗; τ ∗) of the machine; and wherein the current controller comprises a master controller configured to output one of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to the respective outer or inner power electronic converter (6a/6b) and to output a component (Pi ∗; τi ∗) of the at least one operation reference (P ∗; τ ∗) for the other of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to a slave controller based on a pre-defined torque or power split strategy, the slave controller being configured to output the other of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to the respective outer or inner power electronic converter (6a/6b) based on the component (Pi ∗; τi ∗) of the at least one operation reference. an outer stator comprising an outer three-phase winding on an outer core, configured to generate an outer electromagnetic field dependent on an outer three-phase supply current (Io) supplied to the outer stator; an inner stator positioned concentrically inside of the outer stator, the inner stator comprising an inner three-phase winding on an inner core, configured to generate an inner electromagnetic field dependent on an inner three-phase supply current (Ii) supplied to the inner stator; a permanent magnet, PM, rotor configured to be rotated by the outer and inner electromagnetic fields in a gap formed between the outer and inner stators; and a control arrangement configured to control the outer and inner supply currents (Io, Ii), respectively; wherein there is a relative mechanical shift corresponding to an electrical angle of 30° between the outer and inner stators; wherein there is an electrical connection between a neutral point (No) of the outer stator and a neutral point (Ni) of the inner stator; wherein the control arrangement is configured to control the outer and inner supply currents (Io, Ii) such that there is a relative angle shift (Δθ) of 30° between the outer and inner supply currents, corresponding to the relative mechanical shift, and such that a third order current harmonic component (Io3, Ii3) is circulated between the outer and inner stators; wherein the control arrangement comprises an outer power electronic converter configured to output the outer supply current (Io) based on outer voltage references (Vabc ∗ o), and an inner power electronic converter configured to output the inner supply current (Ii) based on inner voltage references (Vabc ∗ i); wherein the control arrangement comprises a current controller configured to output the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) based on at least one operation reference (P ∗; τ ∗) of the machine; and wherein the current controller comprises a master controller configured to output one of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to the respective outer or inner power electronic converter (6a/6b) and to output a component (Pi ∗; τi ∗) of the at least one operation reference (P ∗; τ ∗) for the other of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to a slave controller based on a pre-defined torque or power split strategy, the slave controller being configured to output the other of the outer and inner voltage references (Vabc ∗ o, Vabc ∗ i) to the respective outer or inner power electronic converter (6a/6b) based on the component (Pi ∗; τi ∗) of the at least one operation reference.