Shielded power coupling device
View Patent ↗One or more techniques and/or systems described herein provide a shielded power coupling device, such as may be used to transfer electric power from a stator portion of a computed tomography (CT) apparatus to a rotor portion. The shielded power coupling device comprises a rotor portion and a stator portion, separated by an airgap, respectively comprising one or more windings and a core. The shielded power coupling device further comprises a fringe field mitigation element(s) (e.g., an electrically conductive wire) that is configured to carry an induced current that creates a magnetic field that mitigates, or substantially cancels, magnetic flux generated by current in the windings that escapes from the core near the core airgap.
1. A shielded power coupling device configured to transfer electric power between a stator and a rotor, comprising:
an inductive field generating element configured to convert electric power to an inductive coupling field;
an inductive field receiving element configured to convert the inductive coupling field to electric power;
a primary and secondary core separated by a core airgap; and
a shell defined by a plurality of segments, the plurality of segments coupled together to form a substantially circular structure, the shell comprising:
a fringe field mitigation element comprising an electrically conductive wire that is inserted into the shell once the plurality of segments are coupled together, the fringe field mitigation element configured to mitigate magnetic flux generated by at least one of the inductive field generating element or the inductive field receiving element and escaping from at least one of the primary core or the secondary core near the core airgap, and
a non-fringe field mitigation element.
2. The device of claim 1 , the non-fringe field mitigation element comprising a dielectric material.
3. The device of claim 1 , the non-fringe field mitigation element comprising a discontinuous, electrically conductive material.
4. The device of claim 3 , the electrically conductive wire being substantially continuous across the plurality of segments.
5. The device of claim 1 , the shielded power coupling device configured to transfer electric power operating at a frequency greater than or equal to 20 kHz.
6. The device of claim 1 , the shielded power coupling device configured to transfer electric power from a stator portion of a computed tomography device to a rotor portion of the computed tomography device.
7. The device of claim 1 , the plurality of segments corresponding to the non-fringe field mitigation element.
8. The device of claim 7 , the plurality of segments comprised of a dielectric material.
9. The device of claim 1 , the fringe field mitigation element being adjacent the core airgap.
10. A shielded power coupling device for use in a computed tomography apparatus, comprising:
an inductive field generating element configured to convert electric power to an inductive coupling field;
an inductive field receiving element configured to convert the inductive coupling field to electric power;
a primary and secondary core separated by a core airgap; and
a shell comprising at least two segments that are fastened together to form a substantially toroidal structure, the shell comprising a fringe field mitigation element that is configured to mitigate magnetic flux, escaping from at least one of the primary core or the secondary core near the core airgap, that is generated by at least one of the inductive field generating element or the inductive field receiving element, the fringe field mitigation element comprising an electrically conductive wire that is inserted into the shell once the at least two segments are fastened together.
11. The device of claim 10 , the at least two segments comprising a dielectric material.
12. The device of claim 10 , the at least two segments defining channels into which the electrically conductive wire is inserted.
13. The device of claim 10 , the fringe field mitigation element being adjacent the core airgap.
14. A radiation imaging system, comprising:
a stator;
a rotor configured for movement relative to the stator;
a radiation source coupled to the rotor;
a detector array coupled to the rotor; and
a power coupling device configured to transfer electric power between the stator and the rotor for supplying power to at least one of the radiation source or the detector array, comprising:
an inductive field generating element configured to convert electric power to an inductive coupling field;
an inductive field receiving element configured to convert the inductive coupling field to electric power;
a primary and secondary core separated by a core airgap; and
a shell comprising:
a fringe field mitigation element comprising an electrically conductive wire and configured to mitigate magnetic flux generated by at least one of the inductive field generating element or the inductive field receiving element and escaping from at least one of the primary core or the secondary core near the core airgap, and
a non-fringe field mitigation element comprising at least two segments that are coupled together to form a substantially circular structure, the electrically conductive wire inserted into channels of the at least two segments.
15. The radiation imaging system of claim 14 , the at least two segments comprising a dielectric material.
16. The radiation imaging system of claim 14 , the fringe field mitigation element and the non-fringe field mitigation element being substantially concentric.
17. The radiation imaging system of claim 14 , the fringe field mitigation element being adjacent the core airgap.
18. The radiation imaging system of claim 14 , the radiation source comprising an ionizing radiation source.
19. The radiation imaging system of claim 14 , the radiation source comprising an x-ray source.
20. The radiation imaging system of claim 14 , wherein the radiation imaging system corresponds to a computed tomography (CT) system.