Inductively powered mobile sensor system

• US 10,069,341 B2
• Filed: 03/05/2015
• Issued: 09/04/2018
• Est. Priority Date: 08/21/2007
• Status: Active Grant

• Current Assignee: Auckland UniServices Limited (Auckland University)
• Original Assignee: Auckland UniServices Limited (Auckland University)
• Inventors: Malpas, Simon Charles, Hu, Aiguo, Budgett, David
• Primary Examiner(s): Fleming, Fritz M
• Application Number:
  US14/639,230
• Publication Number:
  US 20150326029A1
• Time in Patent Office: 1,279 Days
• Field of Search: 307104, 320108
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

An inductively powered sensor system includes a primary conductive path 100 capable of being energised to provide an electromagnetic field in a defined space 1. An inductive power pick-up 120 is associated with a sensor 124 and is capable of receiving power from the field to supply the sensor 124. The system includes a first sensing means to sense the power available to the pick-up 120 and control means to increase or decrease the power available to the sensor dependant on the sensed power available. A method of inductively powering a sensor, an inductively powered sensor and an animal enclosure including one or more primary conductive path of an inductive power supply are also disclosed.

Claims

1. An inductive power transfer system, the system comprising:

a primary conductive path capable of being energized to provide an electromagnetic field in a volume;

an inductive power pick-up associated with a device, the pick-up being capable of receiving power available from the field to supply power to the device when located in the volume;

a sensing circuit operable to sense instantaneous power requirements by the device; and

a controller for varying the power available to the pick-up and operable to vary at least one of a magnetic flux density of the field and a frequency of oscillation of the field in response to the sensed instantaneous power requirements by the device to thereby enable the pick-up to not supply power in excess of that required by the device,

wherein the primary conductive path comprises a plurality of primary coils, and

wherein the controller is operable to further control a vector of the field within the volume by controlling a relative magnetic flux density in at least two of the primary coils.

2. A system according to claim 1, wherein the inductive power pick-up comprises at least one pick-up coil.

3. A system according to claim 2, wherein the controller is operable to vary the frequency of oscillation of the field by varying the frequency of the current in the at least one primary coil.

4. A system according to claim 2, wherein the controller is operable to vary the magnetic flux density of the field by varying the magnitude of the voltage applied to the primary coils.

5. A system according to claim 1, wherein the inductive power pick-up comprises additional pick-up coils in different orientations, and a vector sensing unit operable to sense an orientation of the inductive power pick-up relative to the vector of the field.

6. A system according to claim 1, wherein the pick-up comprises a communications module operable to communicate sensed power available to the pick-up to the controller.

7. A system according to claim 6, wherein the communications module is operable to communicate an immediate power requirement of the device to the controller.

8. A method of inductively powering a device located in a volume, the method comprising:

generating an electromagnetic field in the volume by energizing a primary conductive path;

sensing instantaneous power requirements by the device, using a sensing circuit associated with a pick-up, the pick-up being associated with the device and being capable of receiving power available from the field to supply the device; and

varying the field, using a controller associated with the primary conductive path for varying the power available to the pick-up, to vary at least one of a magnetic flux density of the field and a frequency of oscillation of the field in response to the sensed instantaneous power requirements by the device to thereby enable the pick-up to not supply power in excess of that required by the device;

wherein the primary conductive path comprises a plurality of primary coils, the controlling step further comprising controlling a vector of the field within the volume by controlling a relative magnetic flux density in at least two of the primary coils.

9. A method according to claim 8, wherein the inductive power pick-up comprises at least one pick-up coil, the controlling step comprising varying the frequency of oscillation of the field by varying the frequency of the current in the at least one primary coil.

10. A method according to claim 8, wherein the primary conductive path comprises at least one primary coil and the inductive power pick-up comprises at least one pick-up coil, the controlling step comprising varying the magnetic flux density of the field by varying the magnitude of the voltage applied to the at least one primary coil.

11. A method according to claim 8, wherein the inductive power pick-up comprises additional pick-up coils in different orientations, and the method further comprising the step of sensing, using a vector sensing unit, an orientation of the inductive power pick-up coil relative to the vector of the field.

12. A method according to claim 11, wherein the controlling step comprises controlling the field vector dependent on the sensed orientation.

13. A method according to claim 8, further comprising the step of communicating sensed power available to the pick-up to the controller.

14. A method according to claim 13, wherein the communicating step comprises communicating an immediate power requirement of the device to the controller.

15. An inductive power transfer system, the system comprising:

a primary conductive path capable of being energized to provide an electromagnetic field in a volume;

an inductive power pick-up associated with a device, the pick-up being capable of receiving power available from the field to supply power to the device when located in the volume;

a sensing circuit operable to sense instantaneous power available to the pick-up; and

a controller for varying the power available to the pick-up by varying at least one of a magnetic flux density of the field and a frequency of oscillation of the field in response to the sensed instantaneous power available to the pick-up to enable the pick-up to not supply power in excess of that required by the device,

wherein the primary conductive path comprises a plurality of primary coils, and

wherein the controller is operable to vary a vector of the field within the volume by varying a relative magnetic flux density in at least two of the primary coils.

16. An inductive power transfer system, the system comprising:

a primary conductive path capable of being energized to provide an electromagnetic field in a volume;

an inductive power pick-up associated with a device, the pick-up being capable of receiving power from the field to supply power to the device when located in the volume;

a circuit operable to sense or estimate instantaneous power received by the pick-up; and

a controller operable to vary a magnetic flux of the field in order to vary a level of power being transferred from the primary conductive path to the device via the inductive power pick-up in response to changes in the sensed or estimated instantaneous power received by the pick-up during a power supply period to enable the pick-up to not supply power in excess of that required by the device.

17. An inductive power transfer system, the system comprising:

a primary conductive path capable of being energized to provide an electromagnetic field in a volume;

an inductive power pick-up associated with a device, the pick-up being capable of receiving power from the field to supply power to the device when located in the volume;

a circuit operable to sense or estimate instantaneous power received by the pick-up; and

a controller operable to vary a magnetic flux of the field in order to vary a level of power being transferred from the primary conductive path to the device via the inductive power pick-up in response to changes in the sensed or estimated instantaneous power received by the pick-up during a power supply period to match power available at the pick-up to that required by the device.