초록

A brushless starter-generator assembly includes a stator assembly, a rotor including a magnetic hub, the rotor disposed at least partially within the stator assembly and configured to rotate about an axis, and a field coil located radially outward from the rotor with respect to the axis.

대표청구항 ▼

1. A brushless starter-generator assembly, comprising: a stator assembly comprising a stator stack, a magnetic sleeve located around an outer circumference of the stator stack, and a non-magnetic separator located between the stator stack and the magnetic sleeve;a rotor including a magnetic hub and

1. A brushless starter-generator assembly, comprising: a stator assembly comprising a stator stack, a magnetic sleeve located around an outer circumference of the stator stack, and a non-magnetic separator located between the stator stack and the magnetic sleeve;a rotor including a magnetic hub and disposed at least partially within the stator assembly, the rotor configured to rotate about an axis; anda field coil surrounding a portion of the stator assembly and located radially outward from the rotor with respect to the axis, the field coil including first and second field coils within an axial width of the stator stack in a direction of the axis, the first and second field coils spaced apart from each other in the direction of the axis,wherein the magnetic hub has a magnetic permeability that decreases based on a strengthening of a magnetic field generated by the field coil. 2. The brushless starter-generator assembly of claim 1, wherein the field coil includes first and second field coils surrounding two regions of stator stack in a direction of the axis, and the magnetic sleeve includes radial portions located on outer sides of the first and second field coils, respectively, with respect to a center of the stator stack in the direction of the axis. 3. The brushless starter-generator assembly of claim 2, wherein outer circumferences of the first and second field coils contact an inner circumference of the magnetic sleeve. 4. The brushless starter-generator assembly of claim 1, wherein outer circumferences of the first and second field coils contact an inner circumference of the non-magnetic separator. 5. The brushless starter-generator assembly of claim 1, wherein the first and second field coils are embedded within the stator stack. 6. The brushless starter-generator assembly of claim 1, wherein the field coil is located within the stator stack at a longitudinal center of the stator stack. 7. The brushless starter-generator assembly of claim 6, wherein an outer circumference of the field coil contacts an inner surface of the non-magnetic separator. 8. The brushless starter-generator assembly of claim 1, wherein the rotor comprises: a shaft that rotates about the axis;rotor poles fixed with respect to the shaft; andpermanent magnets fixed with respect to the rotor poles,wherein the magnetic hub is located between the permanent magnets and the shaft. 9. The brushless starter-generator assembly of claim 1, wherein the field coil is configured to increase a magnetic saturation of the magnetic hub when a current is applied to the field coil. 10. The brushless starter-generator assembly of claim 1, wherein the field coil is an O-shaped coil centered about the axis and surrounding the axis. 11. The brushless starter-generator assembly of claim 1, further comprising: a housing fixed with respect to the stator; andbearings to support the magnetic hub with respect to the housing. 12. The brushless starter-generator assembly of claim 11, wherein the housing and the stator stack have a substantially cylindrical shape. 13. A system comprising: a brushless starter-generator assembly having a stator assembly comprising a stator stack, a magnetic sleeve located around an outer circumference of the stator stack, and a non-magnetic separator located between the stator stack and the magnetic sleeve, the brushless starter-generator assembly further including a rotor including a magnetic hub, the rotor configured to rotate about an axis, and a field coil located radially outward from the rotor assembly with respect to the axis, the field coil including first and second field coils within an axial width of the stator stack in a direction of the axis, the first and second field coils spaced apart from each other in the direction of the axis; anda control circuit to control a current supplied to the field coil, the current supplied to the field coil controlling a magnetic field generated by the field coil, and the magnetic filed field generated by the field coil controlling a magnetic permeability of the magnetic hub. 14. The system of claim 13, wherein the control circuit includes a detection circuit to detect a characteristic of the brushless starter-generator assembly, and the control circuit is configured to adjust the current to the brushless starter-generator assembly when the characteristic detected passes a predetermined threshold. 15. The system of claim 14, wherein the detection circuit is a fault detection circuit, and the predetermined threshold is a voltage corresponding to a short-circuit. 16. The system of claim 13, further comprising an excitation power supply connected to the field coil, wherein the control circuit controls the current supplied to the field coil by controlling the output of the excitation power supply. 17. The system of claim 13, wherein the rotor of the brushless starter-generator assembly comprises: a shaft to rotate about the axis;rotor poles fixed with respect to the shaft; andpermanent magnets fixed with respect to the rotor poles,wherein the magnetic hub is located between the permanent magnets and the shaft. 18. A method, comprising: rotating a rotor about an axis with respect to a stator assembly to generate an electromagnetic field (EMF), the rotor including a shaft, permanent magnets rotating around the shaft, and a magnetic hub located between the shaft and the permanent magnets, wherein the stator assembly comprises a stator stack, a magnetic sleeve located around an outer circumference of the stator stack, and a non-magnetic separator located between the stator stack and the magnetic sleeve; andadjusting power supplied to a field coil surrounding one or more portions of the stator assembly to adjust a magnetic reluctance of the magnetic hub, the field coil including first and second field coils within an axial width of the stator stack in a direction of the axis, the first and second field coils spaced apart from each other in the direction of the axis. 19. A brushless starter-generator assembly, comprising: a stator assembly comprising a stator stack, a magnetic sleeve located around an outer circumference of the stator stack, and a non-magnetic separator located between the stator stack and the magnetic sleeve;a rotor including a magnetic hub and disposed at least partially within the stator assembly, the rotor configured to rotate about an axis; anda field coil surrounding a portion of the stator assembly and located radially outward from the rotor with respect to the axis, the field coil located within the stator stack at a longitudinal center of the stator stack,wherein the magnetic hub has a magnetic permeability that decreases based on a strengthening of a magnetic field generated by the field coil.