Wireless battery charging system varying magnetic field frequency to maintain a desired voltage-current phase relationship

• US 9,725,003 B2
• Filed: 05/11/2015
• Issued: 08/08/2017
• Est. Priority Date: 08/06/2011
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Boyer, Richard J., Pasha, Brian D., Fuzo, John Victor
• Primary Examiner(s): Siek, Vuthe
• Application Number:
  US14/708,526
• Publication Number:
  US 20150239356A1
• Time in Patent Office: 820 Days
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/12 of the resonant type
• 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
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

An electrical charging system configured to wirelessly charge an energy storage device, such as a battery. The charging system includes an off-transducer in electrical communication with an alternating power source and electromagnetically coupled to an on-vehicle transducer connected to the energy storage device. A controller adjusts a variable frequency oscillator within the power transmitter, thereby changing the frequency of the sourced electrical power. The charging system further includes a phase detection circuit in communication with the controller and the off-transducer and configured to determine a phase difference between the alternating voltage and the alternating current supplied by the power source. The controller is configured to adjust the variable frequency oscillator based on the phase difference such that the frequency of the sourced electrical power maintains the phase difference within a desired range.

Claims

1. An electrical charging system configured to wirelessly charge an energy storage device, said system comprising:

an electrical power transmitter including a variable frequency oscillator configured to source electrical power having an alternating current, an alternating voltage, and a frequency;

a controller operable to adjust the variable frequency oscillator, thereby changing the frequency of the sourced electrical power;

an off-transducer in electrical communication with the electrical power transmitter, configured to be electromagnetically coupled to an on-vehicle transducer that is in electrical communication with said energy storage device, thereby inducing the on-vehicle transducer to capture electrical power to charge the energy storage device; and

a phase detection circuit in communication with the controller and the off-transducer and configured to determine a phase difference between the alternating voltage and the alternating current, wherein the controller is configured to adjust the variable frequency oscillator based on the phase difference such that the frequency of the sourced electrical power maintains the phase difference within a desired range; and

a wireless transmitter in electrical communication with the controller, wherein said on-vehicle transducer is in electrical communication with a power detection circuit configured to determine a value of the captured electrical power, wherein the power detection circuit is in electrical communication with a wireless receiver configured to wirelessly transmit the value of the captured electrical power to the controller via the wireless transmitter, and wherein the controller is configured to determine a power efficiency by comparing the value of the captured electrical power to the value of the sourced electrical power.

2. The system according to claim 1, wherein the controller is configured to adjust the variable frequency oscillator such that the frequency of the sourced electrical power sweeps within a frequency range of 10 kilohertz (kHz) to 450 kHz.

3. The system according to claim 1, wherein the controller is configured to adjust the variable frequency oscillator based on the power efficiency such that the frequency of the sourced electrical power maximizes the power efficiency.

4. The system according to claim 1, wherein the desired range of the phase difference is between 10 and 21 degrees.

5. The system according to claim 4, wherein the desired range of the phase difference is between 10 and 15 degrees.

6. The system according to claim 5, wherein the desired range of the phase difference is between 0 and 10 degrees.

7. The system according to claim 6, wherein the phase difference is about 0 degrees.

8. The system according to claim 1, wherein the on-vehicle transducer and the energy storage device are disposed within a vehicle.

9. The system according to claim 8, wherein the off-transducer and the electrical power transmitter are disposed external to the vehicle.

10. An electrical charging system configured to wirelessly charge an energy storage device, said system comprising:

an electrical power transmitter including a variable frequency oscillator configured to source electrical power having an alternating current, an alternating voltage, and a frequency;

a controller operable to adjust the variable frequency oscillator, thereby changing the frequency of the sourced electrical power;

an off-transducer in electrical communication with the electrical power transmitter, configured to be electromagnetically coupled to an on-vehicle transducer that is in electrical communication with said energy storage device, thereby inducing the on-vehicle transducer to capture electrical power to charge the energy storage device; and

a wireless transmitter in electrical communication with the controller, wherein said on-vehicle transducer is in electrical communication with a power detection circuit configured to determine a value of the captured electrical power, wherein the power detection circuit is in electrical communication with a wireless receiver configured to wirelessly transmit the value of the captured electrical power to the controller via the wireless transmitter, wherein the controller is configured to determine a power efficiency by comparing the value of the captured electrical power to the value of the sourced electrical power, and wherein the controller is configured to adjust the variable frequency oscillator based on the power efficiency such that the frequency of the sourced electrical power maximizes the power efficiency.