ELEVATOR WIRELESS POWER TRANSFER SYSTEM

• US 20170057792A1
• Filed: 08/23/2016
• Published: 03/02/2017
• Est. Priority Date: 08/25/2015
• Status: Active Grant

• Current Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Original Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Inventors: Dwari, Suman, Nguyen, Dang V.
• Granted Patent: US 10,135,299 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B66B 11/0407 actuated by an electrical linear motor in the counterweight B66B17/12
• CPC Class Codes: B66B 9/003 for lateral transfer of car or frame, e.g. between vertical hoistways or to/from a parking position
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

An elevator system includes a car arranged to move along a hoistway and a wireless power transfer system that includes a secondary resonant coil mounted to the car and configured to induce an electro-motive force and output a voltage or current, and a plurality of primary resonant coils distributed along the hoistway and configured to transmit power to the secondary resonant coil when a primary resonant coil is adjacent to the secondary resonant coil and is selectively energized. A control system of the wireless power transfer system is configured to select and energize the plurality of primary resonant coils, and includes a plurality of switches with each one being associated with a respective one of the plurality of primary resonant coils. The plurality of switches are configured to selectively close to energize a selected one of the plurality of primary resonant coils associated with a location of the car.

Claims

1. An elevator system, comprising:

an elevator car disposed in and arranged to move along a hoistway extending in an axial direction;

a secondary resonant coil mounted to the elevator car and configured to get induced an electro-motive force and output a voltage or current;

a plurality of primary resonant coils distributed along the hoistway and configured to transmit power to the secondary resonant coil when a primary resonant coil of the plurality of resonant coils is adjacent to the secondary resonant coil and is selectively energized; and

a control system configured to select and energize the plurality of primary resonant coils, the control system including a plurality of switches with each one of the plurality of switches being associated with a respective one of the plurality of primary resonant coils, and wherein the plurality of switches selectively close to energize a selected one of the plurality of primary resonant coils associated with a location of the elevator car.

2. The elevator system set forth in claim 1, wherein the control system includes a controller configured to control the plurality of switches for selective energization of the plurality of primary resonant coils based on a location of the elevator car.

3. The elevator system set forth in claim 1, wherein the plurality of switches are smart switches.

4. The elevator system set forth in claim 3, wherein the plurality of switches are configured to sequentially close upon at least one of a detected change in capacitance, inductance or impedance across a primary resonant coil of the plurality of primary resonant coils.

5. The elevator system set forth in claim 4, wherein the plurality of switches each include a capacitance sensor, an inductance sensor, or an impedance sensor.

6. The elevator system set forth in claim 3, wherein each one of the plurality of switches include an inductance sensor, and the plurality of switches are configured to sequentially close upon a detected change in inductance across a primary resonant coil of the plurality of primary resonant coils.

7. The elevator system set forth in claim 1, wherein the control system includes a high frequency converter configured to power the plurality of primary resonant coils.

8. The elevator system set forth in claim 7, wherein the high frequency converter outputs power within a range of about 1 kHz to 1 MHz.

9. The elevator system set forth in claim 8, wherein the high frequency converter outputs power within a range of about 50 kHz to 500 kHz.

10. The elevator system set forth in claim 1 further comprising:

the power transmitted to the secondary resonant coil being a high frequency power; and

a passive resonant component carried by the elevator car and configured to receive the high frequency power from the secondary resonant coil and store the power.

11. The elevator system set forth in claim 1 further comprising:

the power transmitted to the secondary resonant coil being a high frequency power; and

a resonant component carried by the elevator car and configured to receive the high frequency power from the secondary resonant coil and mitigate effects of a varying coupling factor.

12. The elevator system set forth in claim 1 further comprising:

the power transmitted to the secondary resonant coil being a high frequency power; and

a power converter carried by the elevator car and configured to convert the frequency of the high frequency power induced by the secondary resonant coil to a desired frequency of the load.

13. The elevator system set forth in claim 12, wherein the power converter provides AC power to AC loads of the elevator car.

14. The elevator system set forth in claim 10 further comprising:

the power transmitted to the secondary resonant coil being a high frequency power;

a power converter carried by the elevator car and configured to convert the high frequency power to a DC power; and

an energy storage device carried by the elevator car and configured to receive and store the DC power from the power converter.

15. The elevator system set forth in claim 14 further comprising:

a DC elevator car load configured to receive the DC power from the energy storage device.

16. The elevator system set forth in claim 1 further comprising:

a plurality of permanent magnets carried by the elevator car, and wherein the plurality of primary resonant coils are configured to sequentially propel the elevator car in the hoistway when proximate to the plurality of permanent magnets.

17. A wireless power transfer system for inductively transferring power to an elevator car constructed to move in a hoistway, the wireless power transfer system comprising:

a secondary resonant coil mounted to the elevator car and configured to get induced an electro-motive force and output a current;

a plurality of primary resonant coils distributed along the hoistway and configured to transmit power to the secondary resonant coil when a primary resonant coil of the plurality of resonant coils is proximate to the secondary resonant coil and is selectively energized;

a power source configure to output a power; and

a high frequency converter configured to convert the power to a high frequency power having a frequency with a range of 1 kHz to 1 MHz and outputting the high frequency power to the primary resonant coil.

18. The wireless power transfer system set forth in claim 17 further comprising:

a power converter carried by the elevator car and configured to reduce the frequency.

19. The wireless power transfer system set forth in claim 17 further comprising:

a power converted carried by the elevator car and configured to convert a high frequency power induced by the secondary resonant coil to a DC power.

20. The wireless power transfer system set forth in claim 17 further comprising:

a control system configured to select and energize the plurality of primary resonant coils, the control system including a plurality of switches with each one of the plurality of switches being associated with a respective one of the plurality of primary resonant coils, and wherein the plurality of switches selectively close to energize a selected one of the plurality of primary resonant coils associated with a location of the elevator car.