THERMAL SYSTEM OF AN ELECTRIC OR HYBRID VEHICLE

Abstract

One aspect of the invention relates to a thermal system 2 of an electric or hybrid vehicle 1 comprising: A refrigerant compressor 9 capable of compressing a refrigerant from a first loop 10; A heat exchanger 11 between the compressor 9 and a fluid from a second loop 12 capable of transporting heat produced by the compressor 9 to a battery 3, a radiator 4 and a cabin heater 5; A first cooling exchanger 13 between the refrigerant and a fluid from a third loop 14 capable of transporting said cooling to the battery 3, the radiator 4 and a rotating electrical machine 8; A second cooling exchanger 15 between said refrigerant and a fluid from a fourth loop 16 capable of transporting said cooling to a cabin cooler 6. Figure 1

Description

Title of the invention: THERMAL SYSTEM FOR AN ELECTRIC OR HYBRID VEHICLE

[0001] The invention relates to a thermal system for an electric or hybrid vehicle using a highly flammable refrigerant, such as propane or difluoroethane. The technical field of the invention is thus that of temperature control for the vehicle's passenger compartment and other vehicle components.

[0002] Air conditioning is a comfort feature increasingly installed in motor vehicles. As is known, a motor vehicle air conditioning system comprises a reversible refrigeration loop in which a refrigerant circulates.

[0003] This type of air conditioning usually comprises four main elements: a compressor, a condenser, an expansion valve, and an evaporator. These four elements are arranged within a closed circuit in which a refrigerant circulates, for example a hydrofluoroolefin-based refrigerant.

[0004] The role of the compressor is to ensure the circulation of the refrigerant in the circuit by drawing in the fluid in its gaseous state, compressing it, and sending it to the condenser as a high-pressure, high-temperature gas. The condenser is a heat exchanger in which the heat transfer fluid changes from a gaseous to a liquid state, a stage during which the fluid releases some of its thermal energy, before passing through the expansion valve. The role of the expansion valve is to reduce the pressure, and therefore the temperature, of the heat transfer fluid. Finally, the role of the evaporator is to change the heat transfer fluid from a liquid to a gaseous state. During this phase change, the heat transfer fluid absorbs heat from the air passing through the evaporator. The cooled air is then sent to the passenger compartment by means of a ventilation system.Upon exiting the evaporator, the heat transfer fluid in its gaseous state is drawn into the compressor and thus begins a new cycle.

[0005] For the preservation of the environment, the use of refrigerant based on hydrofluoroolefins containing perfluoroalkyl and polyfluoroalkyl compounds, better known as PFAS, is now discouraged.

[0006] The object of the invention is to overcome the disadvantages of the prior art by proposing a thermal system for vehicles offering the possibility of using other types of refrigerant fluid contributing to the preservation of the environment.

[0007] In this context, the invention thus relates, in its broadest sense, to a thermal system for an electric or hybrid vehicle, the thermal system comprising: • A refrigerant compressor capable of compressing the refrigerant in a first refrigerant loop; • A heat exchanger between the compressor and a fluid in a second loop capable of transporting heat produced by the compressor to a battery, a radiator and a cabin heater included in the vehicle; • A first heat exchanger between the refrigerant and a fluid from a third loop capable of transporting said heat to the battery, the radiator and a rotating electrical machine included in the vehicle; • A second refrigeration exchanger between the refrigerant and a fluid from a fourth loop capable of transporting said refrigeration to a passenger compartment re-cooler included in the vehicle.

[0008] The thermal system architecture according to the invention is compatible with environmentally friendly fluids, such as propane or difluoroethane. Since these are highly flammable, to ensure the safety of vehicle passengers, this architecture allows the compressor and the first refrigerant loop to be positioned outside the passenger compartment.

[0009] In addition to the characteristics mentioned in the preceding paragraph, the thermal system according to the invention may have one or more additional characteristics from among the following, considered individually or according to all technically possible combinations.

[0010] According to a non-limiting aspect of the invention, the thermal system comprises an electric heater capable of supplying heat to a fluid in a fifth loop capable of transporting said heat to: • The first refrigeration exchanger; • The battery; and • The cabin heater.

[0011] According to a non-limiting aspect of the invention, the electric heater is a heating resistance.

[0012] According to a non-limiting aspect of the invention, the refrigerant is propane.

[0013] According to a non-limiting aspect of the invention, the refrigerant is difluo- roethane.

[0014] According to a non-limiting aspect of the invention, the weight of the refrigerant fluid included in the first refrigerant fluid loop is less than 200 grams.

[0015] According to a non-limiting aspect of the invention, the weight of the refrigerant fluid comprising the first refrigerant fluid loop is less than or equal to 150 grams.

[0016] According to a non-limiting aspect of the invention, the fluid of the second, third, fourth and fifth loops is a fluid composed mainly of water.

[0017] Another aspect of the invention relates to an electric or hybrid vehicle equipped of a thermal system according to any one of the aforementioned aspects of the invention.

[0018] According to a non-limiting aspect of the invention, the thermal system is disposed outside a vehicle passenger compartment, for example in the engine compartment.

[0019] The invention and its various applications will be better understood by reading the following description and examining the accompanying figure.

[0020] [[Fig.1] illustrates, schematically, an electric vehicle equipped with a thermal system according to a non-limiting aspect of the invention.

[0021] Fig. 1 illustrates more particularly an electric vehicle 1 comprising a thermal system 2 according to a non-limiting embodiment of the invention.

[0022] Vehicle 1 includes, in particular: • A battery 3, for example traction battery; • A radiator 4; • A cabin heater 5, better known by the Anglo-Saxon term "heater core"; • A cabin cooler 6, better known by the Anglo-Saxon term "cooler core"; • A passenger compartment 7; and • A rotating electrical machine 8.

[0023] The thermal system 2 includes a refrigerant compressor 9 capable of compressing the refrigerant of a first refrigerant loop 10.

[0024] According to a non-limiting implementation, the refrigerant 10 can be formed from propane or difluoroethane.

[0025] Since propane or difluoroethane are highly flammable fluids, in order to protect the passengers of the vehicle 1, the thermal system 2, and more particularly the compressor 9 and the first loop 10 of refrigerant fluid are located outside the passenger compartment 7.

[0026] According to a non-limiting implementation, the thermal system 2, and more particularly the compressor 9 and the first refrigerant loop 10, are located in the engine compartment of the vehicle 1.

[0027] Since propane or difluoroethane are highly flammable fluids, in order to protect the vehicle's passengers, the weight of the refrigerant fluid in the first refrigerant loop 10 is limited, for example, to 200 grams.

[0028] The thermal system 2 further comprises a heat exchanger 11, more commonly known by the Anglo-Saxon term "water condenser". This heat exchanger 11 is arranged to exchange the heat produced by the compressor 9 to a fluid in a second loop 12 capable of transporting the heat produced by the compressor 9 to the battery 3, the radiator 4 and the cabin heater 5 of the vehicle 1.

[0029] It should be noted that this second loop 12 may include branches so as to circulate the fluid in the battery 3, in the radiator 4, and / or in the cabin heater 5. For clarity, these branches have not been shown.

[0030] According to a non-limiting embodiment, the fluid comprising the second loop 12 is composed mainly of water. It can, for example, be made up of glycol water.

[0031] Thus, when a heating demand is made by the battery 3 and / or the passenger compartment 7, the calories produced by the compressor 9 are transferred to the fluid of the second loop 12 via the heat exchanger 11. The heated fluid of the second loop 12 is then distributed: • To the battery 3; • To the cabin heater 5; or • To the battery and the cabin heater 5.

[0032] The thermal system 2 also includes a first refrigeration exchanger 13, better known under the Anglo-Saxon terminology of "battery chiller", between the refrigerant contained in the first refrigerant loop 10 and a fluid from a third loop 14 suitable for transporting the refrigeration to the battery 3, the radiator 4 and the rotating electrical machine 8.

[0033] According to a non-limiting embodiment, the fluid comprising the third loop 14 is composed mainly of water. It can, for example, be made up of glycol water.

[0034] It should be noted that this third loop 14 may include branches so as to circulate the fluid in the battery 3, the radiator 4 and / or the rotating electrical machine 8. For clarity, these branches have not been shown.

[0035] Thus, the cooling produced by the compressor 9 can be transferred to the fluid of the third loop 14 via the first cooling exchanger 13. The fluid thus cooled can then be distributed: • To battery 3 to recover the calories produced by battery 3; • To radiator 4 to recover calories from the ambient air; and / or • To the rotating electrical machine 8 to recover the calories produced by the rotating electrical machine 8.

[0036] The thermal system 2 also includes a second refrigeration exchanger 15, better known under the Anglo-Saxon terminology of "cabin chiller", between the refrigerant contained in the first refrigerant loop 10 and a fluid from a fourth loop 16 suitable for transporting the refrigeration to the cabin chiller 6.

[0037] According to a non-limiting embodiment, the fluid comprising the fourth loop 16 is composed mainly of water. It can, for example, be formed from glycol water. • According to a non-limiting implementation, the thermal system 2 also includes an electric heater 17 capable of supplying calories to a fluid of a fifth loop 18 capable of transporting said calories to: The battery 3; • The cabin heater 5; and / or • The first refrigeration exchanger 13.

[0038] According to a non-limiting embodiment, the fluid comprising the fifth loop 18 is composed mainly of water. It can, for example, be made up of glycol water.

[0039] It should be noted that this fifth loop 18 may include branches so as to circulate the fluid in the battery 3, the cabin heater 5 and / or the first refrigeration exchanger 13. For clarity, these branches have not been shown.

[0040] Thus, if the calories produced by the compressor 9 are insufficient or if the compressor 9 cannot operate, the electric heater 17, for example formed by a heating resistance, can supplement the supply of calories directly: • To the battery 3; • To the cabin heater 5; and / or • At the first refrigeration exchanger 13.

[0041] According to this embodiment, when a cooling demand is made for the battery 3 and / or the passenger compartment 7, the cooling produced by the compressor 9 is transferred to the third loop 14 via the first cooling exchanger 13 and / or to the fourth loop 16 via the second cooling exchanger 15. The cooled fluid can thus be distributed: • To the battery 3; and / or • To the passenger compartment cooler 6.

[0042] The calories produced by the compressor 9 are, meanwhile, evacuated via the fluid of the second loop 12. The heated fluid of the second loop 12 is distributed to the radiator 4 to evacuate the heat to the ambient air.

[0043] When a request for dehumidification of the passenger compartment 7 requiring both heating and cooling of the passenger compartment 7 is triggered, • The cooling produced by the compressor 9 is transferred to the fourth loop 16 via the second heat exchanger 15, the cooled fluid then being distributed to the cabin cooler 6; • The calories produced by the compressor 9 are dissipated via the fluid of the second loop 12, the heated fluid of the second loop 12 then

[0044]

[0045] distributed to the cabin heater 5; • If the calories produced by the compressor 9 are insufficient, the electric heater 17 can supplement the supply of calories via the fifth loop 18 to the cabin heater 5. It should be noted that the second, third, fourth and fifth loops 12, 14, 16 and 18 may have common parts via unillustrated derivations. The various aspects of the invention mentioned above offer numerous advantages. Among these are: • Use a single radiator 4 to vent: • The calories produced by the compressor 9 and / or by the rotating electrical machine 8; • The calories produced by battery 3; • The cooling capacity produced by the compressor 9; • Use an electric heater 17 as a heat source to enable the compressor 9 to operate under extreme conditions, for example at temperatures below -20°C; • A thermal connection of the electric heater 7 with the battery 3 and the cabin heater 5 provides increased performance in living situations where the production of calories by the compressor 9 is insufficient.

Claims

Demands

1. Thermal system (2) of an electric or hybrid vehicle (1), said thermal system (2) comprising: - A refrigerant compressor (9) capable of compressing a refrigerant from a first refrigerant loop (10); - A heat exchanger (11) between said compressor (9) and a fluid from a second loop (12) capable of transporting heat produced by said compressor (9) to a battery (3), a radiator (4) and a cabin heater (5) included in said vehicle (1); - A first heat exchanger (13) between said refrigerant and a fluid from a third loop (14) capable of transporting said heat to said battery (3), said radiator (4) and a rotating electrical machine (8) included in said vehicle (1);- A second refrigeration exchanger (15) between said refrigerant fluid and a fluid from a fourth loop (16) capable of transporting said refrigeration to a cabin cooler (6) included in said vehicle (1).;

2. Thermal system (2) according to the preceding claim, characterized in that it comprises an electric heater (17) capable of supplying calories to a fluid of a fifth loop (18) capable of transporting said calories to: - The battery (3); - The cabin heater (5); and - The first refrigeration exchanger (13).

3. Thermal system (2) according to the preceding claim, characterized in that the electric heater (17) is a heating resistance.

4. Thermal system (2) according to any one of the preceding claims, characterized in that the refrigerant is propane

5. Thermal system (2) according to any one of claims 1 to 3, characterized in that the refrigerant is difluoroethane.

6. Thermal system (2) according to any one of the preceding claims previous, characterized in that the weight of the refrigerant fluid included in the first loop (10) of refrigerant fluid is less than 200 grams.

7. Thermal system (2) according to the preceding claim, characterized in that the weight of the refrigerant fluid comprising the first loop (10) of refrigerant fluid is less than or equal to 150 grams.

8. Thermal system (2) according to any one of the preceding claims, characterized in that the fluid of the second, third, fourth and fifth loops (12, 14, 16, 18) is a fluid composed mainly of water.

9. Electric or hybrid vehicle (1), characterized in that it comprises a thermal system (2) according to any one of the preceding claims.

10. Vehicle (1) according to the preceding claim, characterized in that the thermal system (2) is disposed outside a passenger compartment (7) of said vehicle (1).

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