Thermal feedback for power transfer optimization

Patent metadata

Field	Value
Publication number	US-10875417-B2
Application number	US-201916246985-A
Country	US
Kind code	B2
Filing date	Jan 14, 2019
Priority date	Feb 6, 2018
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

Systems and methods are described for thermal feedback for power transfer optimization. Aspects include a wireless power-transfer system including a base power-transfer apparatus, a power supply unit, at least one temperature sensor, and a system controller. The base power-transfer apparatus includes a coil configured to generate a magnetic field based on an electric current. The power supply unit includes switching and power electronics configured to drive the electric current in the coil. The temperature sensor(s) are configured to measure a temperature of the base power-transfer apparatus or the power supply unit. The system controller is coupled to the base power-transfer apparatus, the power supply unit, and the temperature sensor(s) and is configured to control operation of at least one of the base power-transfer apparatus or the power supply unit based on the measured temperature to shift losses and dissipate heat in the base power-transfer apparatus or the power supply unit.

First claim

The invention claimed is:

1. A wireless power-transfer system comprising:
a base power-transfer apparatus including a coil configured to generate a magnetic field based on an electric current;
a power supply unit including switching and power electronics configured to drive the electric current in the coil;
at least one temperature sensor configured to measure a temperature of the base power-transfer apparatus or the power supply unit; and
a system controller coupled to the base power-transfer apparatus, the power supply unit, and the at least one temperature sensor, the system controller configured to:
determine whether the measured temperature exceeds an upper temperature value of a defined temperature range; and
responsive to the measured temperature exceeding the upper temperature value, control operation of at least one of the base power-transfer apparatus or the power supply unit based on the measured temperature to:
reduce a power level delivered to the base power-transfer apparatus from a first power level to a second power level that is greater than zero; and
shift losses and dissipate heat in the base power-transfer apparatus or the power supply unit.

2. The wireless power-transfer system of claim 1 , wherein:
the base power-transfer apparatus includes a ferrite layer disposed proximate to the coil; and
the at least one temperature sensor is disposed proximate to the ferrite layer to measure a temperature of the ferrite layer during the operation of the base power-transfer apparatus.

3. The wireless power-transfer system of claim 1 , wherein:
the coil comprises a conductor that follows a path including a plurality of bends; and
the at least one temperature sensor is positioned proximate to one of the plurality of bends.

4. The wireless power-transfer system of claim 1 , wherein the at least one temperature sensor comprises a plurality of temperature sensors including a first temperature sensor disposed proximate to a ferrite layer of the base power-transfer apparatus to measure a first temperature associated with operation of the base power-transfer apparatus and a second temperature sensor disposed at the power supply unit to measure a second temperature associated with operation of the power supply unit.

5. The wireless power-transfer system of claim 1 , wherein the first power level is a nominal full power value, and wherein the power level is reduced by cycling between the nominal full power value and decreasing values of power to decrease the temperature over time.

6. The wireless power-transfer system of claim 1 , wherein the system controller is configured to control the operation of the base power-transfer apparatus or the power supply unit to maintain the measured temperature within a temperature range defined by the upper temperature value and a lower temperature value.

7. The wireless power-transfer system of claim 1 , wherein the system controller is configured to control the operation of the base power-transfer apparatus or the power supply unit by selecting a power mode from a plurality of power modes including a warm-up mode and a cool-down mode, the system controller further configured to:
increase power delivered to the base power-transfer apparatus from the power supply unit in the warm-up mode; and
decrease power delivered to the base power-transfer apparatus from the power supply unit in the cool-down mode.

8. The wireless power-transfer system of claim 1 , wherein the system controller is configured to control the operation of the base power-transfer apparatus or the power supply unit by varying a phase and timing of an input to the coil to shift losses from the coil in the base power-transfer apparatus to the switching and power electronics in the power supply unit.

9. The wireless power-transfer system of claim 1 , wherein the system controller is configured to control the operation of at least one of the base power-transfer apparatus or the power supply unit by:
communicating with a vehicle system controller of a vehicle power-transfer apparatus at least partially aligned with the base power-transfer apparatus;
transmitting a request to the vehicle system controller to increase a third power level of the vehicle power-transfer apparatus to shift the losses from the base power-transfer apparatus to the vehicle power-transfer apparatus and maintain power transfer between the base power-transfer apparatus and the vehicle power-transfer apparatus that is at a level that is the same or higher than as before reducing the power level of the base power-transfer apparatus from the first power level to the second power level.

10. The wireless power-transfer system of claim 1 , wherein the first power level comprises a nominal full power value and the second power level comprises approximately 50% of the nominal full power value.

11. A method of controlling power transfer between a base power-transfer apparatus and a vehicle power-transfer apparatus, the method comprising:
measuring a temperature of at least one component of the base power-transfer apparatus or the vehicle power-transfer apparatus by using at least one temperature sensor;
comparing the measured temperature to a temperature range defined by a lower temperature value and an upper temperature value;
determining that the measured temperature is greater than the upper temperature value; and
responsive to the determining, controlling operation of the at least one component of the base power-transfer apparatus or the vehicle power-transfer apparatus by reducing power delivered to the at least one component from a first power level to a second power level that is greater than zero.

12. The method of claim 11 , wherein the at least one component comprises a power supply unit or a ferrite layer of the base power-transfer apparatus.

13. The method of claim 11 , wherein:
the at least one component includes a coil comprising a conductor that follows a convoluted path including plural bends;
the at least one temperature sensor is disposed proximate to one of the bends; and
the method further comprises using the at least one temperature sensor to measure the temperature associated with the coil.

14. The method of claim 11 , wherein the at least one component comprises a vehicle control unit or a ferrite layer of the vehicle power-transfer apparatus.

15. The method of claim 11 , further comprising:
subsequent to reducing the power delivered to the at least one component, determining that the measured temperature is less than the lower temperature value; and
responsive to the determining, controlling the operation of the at least one component by increasing the power level of the at least one component from the second power level to the first power level.

16. The method of claim 11 , further comprising maintaining the measured temperature within the temperature range by shifting losses to dissipate heat when the temperature exceeds the upper temperature value or when the temperature is less than the lower temperature value.

17. The method of claim 11 , wherein controlling the operation of the at least one component includes selecting a power mode based on the measured temperature, the power mode selected from:
a full-power mode in which the at least one component operates with full power;
a warm-up mode in which power delivered to the at least one component is increased to cause the temperature of the at least one component to increase; and
a cool-down mode in which the power delivered to the at least one component is decreased to cause the temperature of the at least o

Assignees

• Witricity Corp

Inventors

• Islinger Simon
• Percebon Leandro Alberto
• Raabe Stefan
• Pavlovsky Martin

Classifications

• B60L53/62 Primary

  in response to charging parameters, e.g. current, voltage or electrical charge · CPC title

• H02J50/005 Primary

  Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices · CPC title

• B60L53/305

  Communication interfaces · CPC title

• H01F38/14

  Inductive couplings {(for wireless supply or distribution of electric power using inductive coupling H02J50/10)} · CPC title

• H01F2027/406

  Temperature sensor or protection · CPC title