A stator assembly has coils in a distributed winding configuration. A poly-phase switched reluctance motor assembly 3002 may include a stator assembly with multiple coils in a distributed winding configuration. The stator assembly may have a central bore into which a rotor assembly having multiple poles is received and configured to rotate. A method of controlling a switched reluctance motor may include at least three phases wherein during each conduction period a first phase is energized with negative direction current, a second phase is energized with positive current and there is at least one non-energized phase. During each commutation period either the first phase or second phase switches off to a non-energized state and one of the non-energized phases switches on to an energized state with the same direction current as the first or second phase that was switched off. The switched reluctance motor may include a distributed winding configuration.

A stator assembly has coils in a distributed winding configuration. A poly-phase switched reluctance motor assembly 3002 may include a stator assembly with multiple coils in a distributed winding configuration. The stator assembly may have a central bore into which a rotor assembly having multiple poles is received and configured to rotate. A method of controlling a switched reluctance motor may include at least three phases wherein during each conduction period a first phase is energized with negative direction current, a second phase is energized with positive current and there is at least one non-energized phase. During each commutation period either the first phase or second phase switches off to a non-energized state and one of the non-energized phases switches on to an energized state with the same direction current as the first or second phase that was switched off. The switched reluctance motor may include a distributed winding configuration.

An apparatus including a frame, an optical sensor connected to the frame, and an environment separation barrier. The frame is configured to be attached to a housing of a motor assembly proximate an aperture which extends through the housing. The optical sensor comprises a camera. The environment separation barrier is configured to be connected to the housing at the aperture, where the environment separation barrier is at least partially transparent and located relative to the camera to allow the camera to view an image inside the housing through the environment separation barrier and the aperture.

An apparatus including a frame, an optical sensor connected to the frame, and an environment separation barrier. The frame is configured to be attached to a housing of a motor assembly proximate an aperture which extends through the housing. The optical sensor comprises a camera. The environment separation barrier is configured to be connected to the housing at the aperture, where the environment separation barrier is at least partially transparent and located relative to the camera to allow the camera to view an image inside the housing through the environment separation barrier and the aperture.

An actuator may include a stator, a pole; a bobbin; and windings provided around an exterior surface of the bobbin. The stator may include a stator body; and a plurality of magnets circumferentially arranged around an inner surface of the stator body. The stator, the pole, and the bobbin may be coaxial. An outer diameter of the pole may be smaller than an inner diameter of the bobbin such that the bobbin is movable in an axial direction over an exterior surface of the pole. An outer diameter of the bobbin may be smaller than an inner diameter of the stator such that the bobbin is movable in an axial direction inside the plurality of magnets circumferentially arranged around the inner surface of the stator body.

An actuator may include a stator, a pole; a bobbin; and windings provided around an exterior surface of the bobbin. The stator may include a stator body; and a plurality of magnets circumferentially arranged around an inner surface of the stator body. The stator, the pole, and the bobbin may be coaxial. An outer diameter of the pole may be smaller than an inner diameter of the bobbin such that the bobbin is movable in an axial direction over an exterior surface of the pole. An outer diameter of the bobbin may be smaller than an inner diameter of the stator such that the bobbin is movable in an axial direction inside the plurality of magnets circumferentially arranged around the inner surface of the stator body.

A position detection unit generates a position detection value P.sub.FB that indicates the position of a control target. A temperature detection unit generates a temperature detection value that indicates the temperature. A correction unit corrects the position detection value P.sub.FB. A controller generates a control instruction value S.sub.REF such that the position detection value P.sub.FB_CMP subjected to the correction matches a position instruction value P.sub.REF that indicates the target position of the control target. A driver unit applies a driving signal that corresponds to the control instruction value S.sub.REF to an actuator. The correction unit corrects the position detection value P.sub.FB such that the relation between the position detection value P.sub.FB and the actual position exhibits linearity that is uniform independent of the temperature.

A position detection unit generates a position detection value P.sub.FB that indicates the position of a control target. A temperature detection unit generates a temperature detection value that indicates the temperature. A correction unit corrects the position detection value P.sub.FB. A controller generates a control instruction value S.sub.REF such that the position detection value P.sub.FB_CMP subjected to the correction matches a position instruction value P.sub.REF that indicates the target position of the control target. A driver unit applies a driving signal that corresponds to the control instruction value S.sub.REF to an actuator. The correction unit corrects the position detection value P.sub.FB such that the relation between the position detection value P.sub.FB and the actual position exhibits linearity that is uniform independent of the temperature.

In an example, a circuit includes a first comparator, a second comparator, a pulse counter, a processor, a first ADC, and a second ADC. The first comparator has a first input coupled to a first node, a second input, and an output. The second comparator has a first input coupled to a second node, a second input, and an output. A first DAC is coupled to the second input of the first comparator. A second DAC is coupled to the second input of the second comparator. The pulse counter has a first input coupled to the output of the first comparator and a second input coupled to the output of the second comparator. The first ADC has an input coupled to the first node and an output coupled to the processor. The second ADC has an input coupled to the second node and an output coupled to the processor.

An electric actuator apparatus comprising: an electric motor, comprising in turn a stator and a rotor, which is configured to rotate about an axis according to the power transmitted by the stator; a control unit configured to control the electric motor via a feedback control; a position detection system configured to provide the control unit with an angular position of the rotor; a reading portion, which is integral to the rotor and provided with an encoded surface on which a plurality of codes that can be associated with the angular position of the rotor are fixed; an optical or laser sensor element, which is arranged integral to the stator and so as to point toward the encoded surface.