Wireless power transfer system

• US 10,573,455 B2
• Filed: 11/18/2016
• Issued: 02/25/2020
• Est. Priority Date: 11/18/2015
• Status: Active Grant

• Current Assignee: University of Hong Kong (Government of Hong Kong Special Administrative Region)
• Original Assignee: University of Hong Kong (Government of Hong Kong Special Administrative Region)
• Inventors: Hui, Shu Yuen Ron, Zhang, Cheng
• Primary Examiner(s): Sun, Pinping
• Application Number:
  US15/355,978
• Publication Number:
  US 20170140870A1
• Time in Patent Office: 1,194 Days
• CPC Class Codes: H01F 27/24 Magnetic cores
• CPC Class Codes: H01F 27/28 Coils; Windings; Conductive connections
• CPC Class Codes: H01F 27/32 Insulating of coils, windings, or parts thereof
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

Novel and advantageous insulator discs with embedded resonator coils are provided. By linking the insulator discs in a series using an appropriate mechanical mechanism, the insulator discs form an insulator or insulator string for a high power transmission line system. The resonator coils embedded inside the insulator discs therefore form a series of relay resonators that can be used for wireless power transfer through the principle of near-field magnetic coupling and resonance. The insulator string can provide the simultaneous functions of voltage insulation and wireless power transfer over the length of the string. Applications include, but not limited to, wireless power transfer in a high-voltage environment such as that encountered in high-voltage power transmission line systems.

Claims

1. An insulator device, comprising:

a first insulator disc comprising a first body formed of a first electrically insulating material and defining a first cavity;

a second insulator disc comprising a second body formed of a second electrically insulating material and defining a second cavity;

a first resonator coil located within the first cavity, embedded in the first body;

a second resonator coil located within the second cavity, embedded in the second body, wherein the first resonator coil is configured for resonant inductive coupling with the second resonator coil when the first resonator coil is in a vicinity of the second resonator coil; and

a shaft connected to a center of the first body and a center of the second body,

wherein the first insulator disc is physically spaced apart from the second insulator disc, and

wherein the insulator device is wirelessly coupled to a circuit to transmit electrical energy from a high voltage power transmission system having a voltage larger than 1,000 V.

2. The insulator device of claim 1, wherein the first resonator coil comprises a coil connected in parallel with a resonator capacitor to form an inductive-capacitor resonator tank such that a resonance frequency of the inductive-capacitor resonator bank is determined by an inductance of the coil and a capacitance of the resonator capacitor.

3. The insulator device of claim 1, wherein the first electrically insulating material is the same as the second electrically insulating material and comprises a material rated for use in the high voltage power transmission system having the voltage larger than 1,000 V.

4. The insulator device of claim 1, comprising an insulator string comprising a series of connected insulator discs including the first insulator disc and the second insulator disc.

5. The insulator device of claim 1, wherein the first cavity of the first body of the first insulator disc is sealed, and

wherein the second cavity of the second body of the second insulator disc is sealed.

6. The insulator device of claim 1, wherein the first body of the first insulator disc comprises first means for connecting the first insulator disc to the shaft, and

wherein the second body of the second insulator disc comprises second means for connecting the second insulator disc to the shaft.

7. The insulator device of claim 1, wherein the first body has means provided on top and bottom surfaces thereof for connecting the first insulator disc respectively to two adjacent insulator discs.

8. The insulator device of claim 1, wherein the first resonator coil comprises at least one ferromagnetic material component in a central region thereof, and wherein the shaft is flexible.

18. The wireless power transfer system of claim 7, wherein the energy transmitting coil comprises a part of an energy harvesting circuit that is configured to wirelessly harvest the electrical energy from a high voltage power transmission line having a voltage larger than 1,000 V.

19. The wireless power transfer system of claim 18, wherein the energy harvesting circuit is configured to convert the electrical energy harvested into a high frequency AC signal having a frequency higher than 20,000 Hz for driving the energy transmitting coil.

20. The wireless power transfer system of claim 7, wherein the energy receiving coil comprises a part of a circuit configured to convert a received high frequency AC signal having a frequency higher than 20,000 Hz into a voltage or current output suitable for powering one or more monitoring apparatuses for a power transmission system.

21. The wireless power transfer system of claim 7, wherein the resonator coil in each insulator disc of the plurality of insulator discs comprises at least one ferromagnetic material component in a central region thereof, and wherein the shaft is flexible.

9. An insulator, comprising:

a series of connected insulator discs, which includes a plurality of insulator discs, each insulator disc of the plurality of insulator discs comprising a body formed of an electrically insulating material and defining a cavity, and a resonator coil located within the cavity, embedded in the body, and configured for resonant inductive coupling with a second resonator coil located in a second cavity of a second insulator disc when the resonator coil is placed in a vicinity of the second resonator coil; and

a shaft connecting the plurality of insulator discs,

wherein each insulator disc of the plurality of insulator discs having the resonator coil is arranged within the series of connected insulator discs so as to enable a near field transmission of electrical energy from a first end of the series of connected insulator discs to a second end of the series of connected insulator discs, and

wherein each insulator disc of the plurality of insulator discs is physically spaced apart from every other insulator disc of the plurality of insulator discs, and

wherein the insulator is wirelessly coupled to a circuit to transmit the electrical energy from a high voltage power transmission system having a voltage larger than 1,000 V.

10. The insulator of claim 9, wherein the plurality of insulator discs comprises all of the insulator discs of the series of connected insulator discs.

11. The insulator of claim 9, wherein the series of connected insulator discs comprises a wireless power transfer domino-resonator system to direct a flow of the electrical energy from the first end of the series of connected insulator discs to the second end of the series of connected insulator discs.

12. The insulator of claim 9, wherein in the plurality of insulator discs, each insulator disc of the plurality of insulator discs having the resonator coil is arranged within the series of connected insulator discs so as to enable the near field transmission of the electrical energy from the second end of the series of connected insulator discs to the first end of the series of connected insulator discs.

13. The insulator of claim 9, wherein the insulator is configured to mechanically support a power transmission cable.

14. The insulator of claim 9, wherein the resonator coils embedded inside the plurality of insulator discs are identical for an optimal transmission of the electrical energy from the first end of the series of connected insulator discs to the second end of the series of connected insulator discs.

15. The insulator of claim 9, wherein a distance between adjacent insulator discs is less than a diameter of the resonator coil embedded in the cavity such that a mutual coupling factor between the adjacent insulator discs is large enough for an efficient transmission of the electrical energy from the first end of the series of connected insulator discs to the second end of the series of connected insulator discs.

16. The insulator of claim 9, wherein the resonant coil in each insulator disc of the plurality of insulator discs comprises at least one ferromagnetic material component in a central region thereof, and wherein the shaft is flexible.

17. A wireless power transfer system, comprising:

the insulator according to claim 9;

an energy transmitting coil magnetically coupled to a first resonator coil of a first insulator disc of the plurality of insulator discs, disposed at the first end of the series of connected insulator discs, for wirelessly delivering the electrical energy to the first resonator coil of the first insulator disc; and

an energy receiving coil magnetically coupled to a second resonator coil of a second insulator disc of the plurality of insulator discs, disposed at the second end of the series of connected insulator discs, for wirelessly receiving the electrical energy from the second resonator coil of the second insulator disc.