Apparatus and method for low grade heat recovery in an electric vehicle

Patent metadata

Field	Value
Publication number	US-11958334-B2
Application number	US-201916970354-A
Country	US
Kind code	B2
Filing date	Jan 21, 2019
Priority date	Feb 16, 2018
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

A heat recovery system for an electric vehicle, including first and second switchable heat sources and a controller operable to selectively switch one of the heat sources into thermal communication with a compressor in a thermodynamic cycling system, the thermodynamic cycling system being in thermal communication with a heat sink; and a detector of a temperature differential between each of the switchable heat sources and a fluid entering the compressor; wherein the controller is operable to switch one of the first and second switchable heat sources into thermal communication with the thermodynamic cycling system when a temperature differential is detected between the fluid entering the compressor in the thermodynamic cycling system and the heat available from the switchable heat source, the temperature differential being such that the compressor is operable to upgrade low grade heat from the switchable heat source to a higher grade heat upon operation of the compressor.

First claim

The invention claimed is:

1. A heat recovery system for an electric vehicle, comprising first and second switchable heat sources and a controller operable to selectively switch one of the heat sources into thermal communication with a compressor in a thermodynamic cycling system, the thermodynamic cycling system being in thermal communication with a heat sink; and a detection means operable to detect a temperature differential between each of the switchable heat sources and a fluid entering the compressor;
wherein the controller is operable to switch one of the first and second switchable heat sources into thermal communication with the thermodynamic cycling system when a temperature differential is detected between the fluid entering the compressor in the thermodynamic cycling system and the switchable heat source, the compressor being operable to upgrade low grade heat from the switchable heat source to a higher grade heat upon operation of the compressor.

2. The system according to claim 1 , wherein the first and second switchable heat sources are each in thermal communication with a fluid within the thermodynamic cycling system and the controller is operable to actuate at least one control valve which is operable to selectively switch the fluid in thermal communication with one of the switchable heat sources into thermal communication with the compressor in the thermodynamic cycling system, wherein the controller is operable to actuate the at least one control valve to switch one of the first and second switchable heat sources into thermal communication with the thermodynamic cycling system when a temperature differential is detected between a fluid entering the compressor in the thermodynamic cycling system and the switchable heat source, the temperature differential being such that the compressor is operable to upgrade low grade heat from the switchable heat source to a higher grade heat upon operation of the compressor.

3. The system according to claim 2 , wherein the controller is operably linked to the detection means and is operable to actuate the at least one control valve such that one of the heat sources is switched into thermal communication with the thermodynamic cycling system in response to the detection means detecting the temperature differential between at least one of: the first switchable heat source and the thermodynamic cycling system and the second switchable heat source and the thermodynamic cycling system.

4. The system according to claim 1 , wherein the temperature differential is at least 5 Kelvin.

5. The system according to claim 1 , wherein the temperature is higher at the first or second switchable heat source than in the fluid entering the compressor.

6. The system according to claim 1 , wherein the detection means is configured to monitor a temperature differential between the first switchable heat source and the fluid entering the compressor and between the second switchable heat source and the fluid entering the compressor in sequence.

7. The system according to claim 1 , wherein the detection means comprises one or more temperature sensors.

8. The system according to claim 1 , wherein the thermodynamic cycling system comprises a first single phase fluid system comprising at least one heat exchanger, a multiphase fluid system in fluid communication with the at least one heat exchanger and comprising the compressor downstream of the heat exchanger and a second single phase fluid system downstream of the compressor and comprising at least one heat exchanger, the first single phase, the multiphase fluid and the second single phase fluid systems being consecutively in thermal communication with one another.

9. The system according to claim 8 , wherein the second single phase fluid or coolant system comprises at least one heat exchanger in thermal communication with the heat sink.

10. The system according to claim 8 , wherein the second single phase fluid or coolant system comprises at least one valve controllable to switch single phase fluid flow to a heat exchanger in thermal communication with a second heat sink.

11. The system according to claim 10 , wherein the second heat sink is a traction battery.

12. The system according to claim 11 , wherein the heat exchanger in thermal communication with the second heat sink is in further thermal communication with the first heat sink.

13. The system according to claim 8 , wherein the thermodynamic cycling system comprises a coolant system comprising at least one heat exchanger, a refrigerant system in fluid communication with the at least one heat exchanger and comprising the compressor downstream of the heat exchanger and a second coolant system downstream of the compressor and comprising at least one heat exchanger, the coolant and refrigerant systems being consecutively in thermal communication with one another.

14. The system according to claim 1 , wherein the thermodynamic cycling system comprises an ambient air capture unit system comprising at least one heat exchanger, a refrigerant system in fluid communication with the at least one heat exchanger and comprising the compressor downstream of the heat exchanger and a coolant system downstream of the compressor and comprising at least one heat exchanger, the coolant and refrigerant systems being consecutively in thermal communication with one another.

15. The system according to claim 14 , wherein the ambient air capture unit system comprises at least one heat exchanger being a condenser or wherein the ambient air capture unit system comprises at least one heat exchanger being an evaporator or a dehumidifier.

16. The system according to claim 1 , wherein the heat sink is one of a passenger cabin and a traction battery.

17. A vehicle comprising an engine and the heat recovery system according to claim 1 , wherein the heat sink is one or more of a passenger cabin and a traction battery.

18. A method of recovering low grade heat energy in an electric vehicle, comprising providing first and second switchable low grade heat sources;
providing a thermodynamic cycling system comprising first and second fluids in thermal communication with each of the first and second switchable low grade heat sources respectively;
detecting a temperature differential between a fluid entering a compressor in the thermodynamic cycling system and the heat available from the first and the second switchable heat source,
switching the first or second fluid in thermal communication with one of the switchable heat sources into thermal communication with a compressor in the thermodynamic cycling system when the temperature differential is such that the compressor is operable to upgrade low grade heat from the switchable heat source to a higher grade heat upon operation of the compressor;
transferring the higher grade heat to a heat sink.

Assignees

• Jaguar Land Rover Ltd

Inventors

• Chatham Chris
• Asokan Dhillip
• Rouse Kate
• Stocks Oliver
• Dutta Nilabza
• Cook Richard

Classifications

• B60H1/00392 Primary

  for electric vehicles having only electric drive means · CPC title

• B60H1/00278 Primary

  for the battery · CPC title

• B60H1/00428

  electric · CPC title

• B60H1/03

  and from a source other than the propulsion plant · CPC title

• B60H1/143

  the heat being derived from cooling an electric component, e.g. electric motors, electric circuits, fuel cells or batteries · CPC title