ELECTRIC OR HYBRID VEHICLE THERMAL SYSTEM

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 of a first loop 10; A heat exchanger 11 between the compressor 9 and a fluid of a second loop 12 capable of transporting calories produced by the compressor 9 to a battery 3, a radiator 4 and a passenger compartment heater 5; A first cold exchanger 13 between the refrigerant and a fluid of a third loop 14 capable of transporting said colds to the battery 3, the radiator 4 and a rotating electrical machine 8; A second cold exchanger 15 between said refrigerant and a fluid of a fourth loop 16 capable of transporting said colds to a passenger compartment cooler 6. Figure 1

Description

Title of the invention: THERMAL SYSTEM OF 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, for example, propane or difluoroethane. The technical field of the invention is thus that of regulating the temperature of the vehicle interior and other vehicle components.

[0002] Air conditioning is a comfort element that is increasingly often installed in motor vehicles. As is known, an air conditioning system for a motor vehicle comprises a reversible refrigeration loop in which a refrigerant fluid 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 (or cooling fluid) 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 sucking this fluid in the gaseous state, compressing this fluid and sending it to the condenser in the form of gas at high pressure and high temperature. The condenser is a heat exchanger in which the heat transfer fluid passes from the gaseous state to the liquid state, a step during which the fluid releases part of its thermal energy, before passing into the expansion valve. The role of the expansion valve is to drop 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 the liquid state to the gaseous state. During this phase change, the heat transfer fluid absorbs the heat from the air passing through the evaporator. The air thus cooled is sent to the passenger compartment by means of a ventilation system.At the evaporator outlet, the heat transfer fluid in gaseous state is sucked in by the compressor and thus begins a new cycle.

[0005] For the preservation of the environment, the use of refrigerant fluid based on hydrofluoroolefins containing perfluoroalkyl and polyfluoroalkyl compounds, better known as PFAS, is currently not recommended.

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

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

[0008] The architecture of the thermal system according to the invention is compatible with fluids that contribute to environmental preservation, such as propane or difluoroethane. Since the latter are highly flammable, in order to ensure the safety of the vehicle's passengers, this architecture offers the possibility of positioning the compressor and the first refrigerant loop outside the passenger compartment.

[0009] In addition to the characteristics which have just been mentioned in the preceding paragraph, the thermal system according to the invention may have one or more complementary characteristics 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 calories to a fluid of a fifth loop capable of transporting said calories to: • The first cold exchanger; • The battery; and • The cabin heater.

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

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

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

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

[0015] According to a non-limiting aspect of the invention, the weight of the refrigerant fluid that the first refrigerant loop comprises 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 provided with of a thermal system according to any of the aforementioned aspects of the invention.

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

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

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

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

[0022] The vehicle 1 comprises in particular: • A 3 battery, for example traction; • A radiator 4; • A cabin heater 5, better known under the Anglo-Saxon terminology of “heater core”; • A cabin cooler 6, better known under the Anglo-Saxon terminology of “cooler core”; • A 7 passenger compartment; and • A rotating electrical machine 8.

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

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

[0025] As 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 refrigerant loop 10 are arranged 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 arranged in the engine compartment of the vehicle 1.

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

[0028] The thermal system 2 further comprises a heat exchanger 11, better known by the English terminology of "water condenser". This heat exchanger 11 is arranged to exchange the heat produced by the compressor 9 to a fluid of a second loop 12 capable of transporting the heat produced by the compressor 9 to the battery 3, the radiator 4 and the passenger compartment heater 5 that the vehicle 1 comprises.

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

[0030] According to a non-limiting implementation, the fluid that the second loop 12 comprises is composed mainly of water. It can for example be formed by glycolated water.

[0031] Thus, when a heating request 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 calorie exchanger 11. The heated fluid of the second loop 12 is then distributed: • To the battery 3; • To the passenger compartment heater 5; or • To the battery and the cabin heater 5.

[0032] The thermal system 2 also comprises a first cold exchanger 13, better known by the English terminology of “battery chiller”, between the refrigerant fluid contained in the first refrigerant loop 10 and a fluid of a third loop 14 capable of transporting the cold to the battery 3, the radiator 4 and the rotating electrical machine 8.

[0033] According to a non-limiting implementation, the fluid that the third loop 14 comprises is composed mainly of water. It can for example be formed by glycolated water.

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

[0035] Thus, the frigories produced by the compressor 9 can be transferred to the fluid of the third loop 14 via the first frigory 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 comprises a second cold exchanger 15, better known by the English terminology of "cabin chiller", between the refrigerant fluid contained in the first refrigerant loop 10 and a fluid from a fourth loop 16 capable of transporting the cold to the cabin cooler 6.

[0037] According to a non-limiting implementation, the fluid that the fourth loop comprises 16 is composed mainly of water. It can, for example, be formed by glycolated water. • According to a non-limiting implementation, the thermal system 2 also 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 passenger compartment heater 5; and / or • The first cold exchanger 13.

[0038] According to a non-limiting implementation, the fluid that the fifth loop 18 comprises is composed mainly of water. It can for example be formed by glycolated water.

[0039] It should be noted that this fifth loop 18 may include bypasses so as to circulate the fluid in the battery 3, the passenger compartment heater 5 and / or the first cold exchanger 13. For reasons of clarity, these bypasses 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 resistor, can supplement the supply of calories directly: • To the battery 3; • To the passenger compartment heater 5; and / or • At the first cold exchanger 13.

[0041] According to this embodiment, when a request for cooling of the battery 3 and / or of the passenger compartment 7 is made, the frigories produced by the compressor 9 are transferred to the third loop 14 via the first frigory exchanger 13 and / or to the fourth loop 16 via the second frigory 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, for their part, 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 controlled, • The cold 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 passenger compartment cooler 6; • The calories produced by the compressor 9 are evacuated via the fluid of the second loop 12, the heated fluid of the second loop 12 then being

[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 passenger compartment heater 5. It should be noted that the second, third, fourth and fifth loops 12, 14, 16 and 18 may have common parts via derivations not shown. The various aspects of the invention mentioned above have numerous advantages. Among these, we can cite: • Use a single radiator 4 to evacuate: • The calories produced by the compressor 9 and / or by the rotating electrical machine 8; • The calories produced by battery 3; • The frigories produced by 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 passenger compartment heater 5 providing increased performance in living situations where the production of calories by the compressor 9 is insufficient.

Claims

Claims

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 calories produced by said compressor (9) to a battery (3), a radiator (4) and a passenger compartment heater (5) included in said vehicle (1); - A first cold exchanger (13) between said refrigerant and a fluid from a third loop (14) capable of transporting said cold to said battery (3), said radiator (4) and a rotating electrical machine (8) included in said vehicle (1);- A second refrigerant exchanger (15) between said refrigerant fluid and a fluid of a fourth loop (16) capable of transporting said refrigerants to a passenger compartment 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 passenger compartment heater (5); and - The first cold exchanger (13).

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

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

7. Thermal system (2) according to the preceding claim, characterized in that the weight of the refrigerant fluid included in the first refrigerant loop (10) 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 arranged outside a passenger compartment (7) of said vehicle (1).

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