Thermal management system for a motor vehicle and motor vehicle having such a thermal management system

Abstract

The invention relates to a thermal management system for a motor vehicle, comprising a motor cooling circuit (1) in which an electric drive device (2), a chiller line branch point (3), a cooler (4) and a motor circuit pump (6) are arranged, a chiller line (7) with a chiller (8), which branches off from the motor cooling circuit at the chiller line branch point and opens into the motor cooling circuit at a point between the cooler and the motor circuit pump, and a heating line (15) with an interior space heat exchanger (20), which branches off from the motor cooling circuit at a point between the motor circuit pump and the electric drive device and opens into the motor cooling circuit at a point between the chiller line branch point and the cooler. Furthermore, the invention relates to a motor vehicle with such a thermal management system.

Description

TECHNICAL FIELD

[0001] The present application relates to a thermal management system for a motor vehicle and to a motor vehicle having such a thermal management system. BACKGROUND

[0002] Thermal management systems are known for electrified motor vehicles, which provide a thermal power for the vehicle interior by means of a heat pump function, in which an existing heat source, such as an electric motor and a high-voltage accumulator, is utilized. Here, it is always desirable to design the thermal management system more efficiently and to utilize the available heat sources more efficiently, since an increase in efficiency directly improves the range of the vehicle in heating operation.

[0003] An alternative thermal management system is described in the unpublished German patent application 102019120229.9. However, in this thermal management system, the heating line branches into the motor cooling circuit upstream of the chiller line branching point. SUMMARY

[0004] It is therefore the task of the present application to improve the efficiency of the thermal management system. This task is solved by the thermal management system according to the present application and by the motor vehicle according to the present application.

[0005] According to one embodiment of the present application, a thermal management system for a motor vehicle is provided, comprising a motor cooling circuit, in which an electric drive device, a chiller line branching point, a cooler and a motor circuit pump are arranged, a chiller line having a chiller, which branches off from the motor cooling circuit at the chiller line branching point and opens into the motor cooling circuit at a point between the cooler and the motor circuit pump, and a heating line having an interior space heat exchanger, which branches off from the motor cooling circuit at a point between the motor circuit pump and the electric drive device and opens into the motor cooling circuit at a point between the chiller line branching point and the cooler. The advantage of this embodiment is that the thermal management system can be realized with as few valves as possible. Thereby, the thermal management system can be produced more cost-advantageously compared to systems known from the prior art. In addition, the interconnection of the heating and cooling circuits of this embodiment allows the waste heat of the electric drive device to be introduced into the chiller and / or into an accumulator without bypassing the cooler. Thereby, no heat losses occur on the cooler, so that a more efficient thermal management system is provided in heating operation (heating operation of the accumulator and / or by means of the chiller).

[0006] According to another embodiment of the present application, the thermal management system is further equipped with a motor-chiller circuit, in which the electric drive device, the chiller and the motor circuit pump are arranged, which motor-chiller circuit leads from the chiller to the motor circuit pump without bypassing the cooler.

[0007] According to another embodiment of the application, the thermal management system is further equipped with an AC circuit having a heating line, a chiller and a motor circuit pump.

[0008] According to another embodiment of the application, the thermal management system is further equipped with an HVS-chiller circuit having a chiller and an electric accumulator.

[0009] According to another embodiment of the application, the thermal management system is further equipped with a heating circuit having an interior space heat exchanger and an electric heater.

[0010] According to another embodiment of the application, the thermal management system is further equipped with a refrigeration circuit having a chiller, an air conditioning evaporator and a water-cooled condenser, the chiller being flowable through by a refrigerant of the refrigeration circuit and flowable through by a coolant of the motor cooling circuit and / or the motor-chiller circuit fluidly separated from the refrigerant of the refrigeration circuit, and the air conditioning evaporator being arranged in an air guiding device by means of which air can be guided into a vehicle passenger compartment.

[0011] According to another embodiment of the application, the electric drive device has at least one electric motor for driving the motor vehicle.

[0012] According to another embodiment of the application, the electric drive device further has an inverter, a DC converter, a battery control device and / or a vehicle interior charger.

[0013] Furthermore, the application relates to a motor vehicle having such a thermal management system. BRIEF DESCRIPTION OF DRAWINGS

[0014] A preferred embodiment of the application is described below with reference to the accompanying drawings. In the drawings:

[0015] Figure 1 schematically showing a heating and cooling circuit of a thermal management system according to a first embodiment of the application;

[0016] Figure 2 schematically showing a refrigeration circuit of a thermal management system according to an embodiment of the application; and

[0017] Figure 3 schematically showing a heating and cooling circuit of a thermal management system according to a second embodiment of the application. DETAILED DESCRIPTION

[0018] Figure 1A heating and cooling circuit of a thermal management system according to an embodiment of the application is schematically shown. The thermal management system is preferably installed in a not shown motor vehicle, in particular a passenger car, such as an electric vehicle. The heating and cooling circuit of the thermal management system comprises a motor cooling circuit 1 in which an electric drive 2 driving the motor vehicle is arranged. The electric drive 2 has at least one electric motor. In the case of a plurality of electric motors, these can be flowed through in parallel to each other by the motor cooling circuit 1, for which the motor cooling circuit 1 branches upstream of the electric motors into parallel lines, which lines are rejoined downstream of the electric motors. Furthermore, the electric drive 2 can also have power electronics components, such as inverters, DC / DC converters, battery control devices and on-board chargers, which are respectively assigned to the electric motors. Downstream of the electric drive 2, a refrigerant circuit branch point 3 with a refrigerant valve 3a, a cooler 4, a compensation vessel 5 and a motor circuit pump 6 are arranged. The cooler 4 is arranged to be flowable through by ambient air, so that the cooler can be cooled by driving air. The cooler is provided with a fan in order to additionally to the driving air to transport air through the cooler. The compensation vessel 5 can also be installed at other points in the heating and cooling circuit and / or one or more compensation vessels can be provided.

[0019] A coolant, such as water with additives, can be circulated in the motor cooling circuit 1. The flow through the cooler 4 can be allowed or prevented by means of the refrigerant valve 3a at the refrigerant circuit branch point 3, wherein an intermediate position of the refrigerant valve 3a is also possible. For example when the motor cooling circuit 1 is running, with the refrigerant valve 3a open and the motor circuit pump 6 activated, the coolant is thus circulated in the motor cooling circuit 1 so that a series connection, in particular in this order, of the electric drive 2, the refrigerant valve 3a, the cooler 4, the motor circuit pump 6 and back to the electric drive 2 is flowed through. In the context of this description, the terms "upstream" and "downstream" relate to the flow direction of the coolant or of the refrigerant mentioned later when the thermal management system is running.

[0020] At the refrigerant circuit branch point 3, a refrigerant circuit 7 branches off from the motor cooling circuit 1, so that the flow through the refrigerant circuit 7 and the cooler 4 is allowed or prevented by means of the refrigerant valve 3a, wherein an intermediate position is also possible. The refrigerant valve 3a is in particular configured as a two-position three-way valve, but instead of a two-position three-way valve one or more other valves, such as two (or three) shut-off valves, can also be provided.

[0021] The refrigerant circuit 7 has a refrigerant 8 and downstream of the refrigerant 8, more precisely upstream of the motor circuit pump 6 or between the cooler 4 and the motor circuit pump 6, rejoins into the motor cooling circuit 1. The refrigerant 8 is a heat exchanger which, in the shown heating and cooling circuit, more precisely in the refrigerant circuit 7 and in the refrigerant circuit 30 explained later, transfers thermal energy. Figure 1 The shown heating and cooling circuit, more precisely the refrigerant circuit 7 and the refrigerant circuit 30 explained later, transfers thermal energy.

[0022] Between the chiller 8 and the access of the chiller line 7 into the motor cooling circuit 1 a HVS line is branched off in which a HVS pump 9, a HVS valve 10, an electric accumulator 11, a non-return valve 12 or check valve are arranged. The HVS line opens into the chiller line 7 at a point between the chiller line branch point 3 and the chiller 8.

[0023] The HVS pump 9 is for example an electric pump, in particular with variable delivery volume. The HVS valve 10 is a shut-off valve through which the flow through the electric accumulator 11 can be allowed or blocked, wherein an intermediate position is also possible, so that the flow rate can be adjusted. The electric accumulator 11 is a rechargeable battery with a plurality of storage battery cells which store and provide energy for driving the vehicle. In the flow through the electric accumulator 11, more precisely a temperature regulation unit of the electric accumulator 11, which is adapted to introduce heat energy into the storage battery cells and / or to discharge heat energy.

[0024] Thus, a HVS-chiller circuit 13 can be constituted when the HVS valve 10 is open and the HVS pump 9 is activated, which HVS-chiller circuit is shown in dashed lines in Figure 1 . In the HVS-chiller circuit 13 the HVS pump 9, the HVS valve 10, the electric accumulator 11, the non-return valve 12 and the chiller 8 are arranged in series in the circuit, for example in the order mentioned, and can be flowed through by coolant.

[0025] If the chiller valve 3a blocks the flow through the chiller line 7 during operation of the HVS-chiller circuit 13, the coolant is circulated in the HVS-chiller circuit 13 without coolant flowing from the chiller line branch point 3 into the chiller line 7 and without coolant flowing from the chiller line 7 into the motor cooling circuit 1.

[0026] By constituting the HVS-chiller circuit 13, coolant is delivered from the accumulator 11 to the chiller 8 by the activated HVS pump 9 and thus the waste heat of the accumulator 11 is input into the chiller 8. After the flow through the chiller 8, the HVS pump 9 delivers the coolant back to the accumulator 11 or the like.

[0027] If the chiller valve 3a opens the flow through the chiller line 7 during operation of the HVS-chiller circuit 13, the coolant is circulated in the HVS-chiller circuit 13 while coolant flows from the chiller line branch point 3 into the chiller line 7 and coolant flows from the chiller line 7 into the motor cooling circuit 1. This additionally forms a motor-chiller circuit 14, which motor-chiller circuit is shown in dot-dashed lines in Figure 1 .

[0028] In the operation of the motor-refrigerator circuit 14, the coolant successively flows through the refrigerator 8, the motor circuit pump 6, the electric drive 2, the refrigerator valve 3a and back again to the refrigerator 8. As already mentioned above, this motor-refrigerator circuit 14 can be operated simultaneously with the HVS-refrigerator circuit 13. But the motor-refrigerator circuit can also be operated in the case of a switch-off of the HVS-refrigerator circuit 13, wherein the HVS-refrigerator circuit 13 is switched off in such a way that the HVS valve 10 prevents the flow through the HVS line and the HVS pump 9 is switched off. When the motor-refrigerator circuit 14 is operated together with the HVS-refrigerator circuit 13, the waste heat of the accumulator 11 and the waste heat of the electric drive 2 can both be fed into the refrigerator 8 and said waste heat can be introduced into the heating line 15 explained later by means of the refrigeration circuit 30.

[0029] If the motor-refrigerator circuit 14 is operated and the HVS-refrigerator circuit 13 is switched off or not operated, the refrigeration circuit 30 is preferably also switched off, so that the refrigerator 8 is essentially not operated. Thereby, the waste heat of the electric drive 2 is fed into the accumulator 11, so that the accumulator 11 can be heated by means of this waste heat. This is for example meaningful at cold ambient temperatures.

[0030] The heating line 15 branches off from the motor cooling circuit 1 at a heating line branching point 25 downstream of the motor circuit pump 6 or between the motor circuit pump 6 and the electric drive 2. The heating line 15 leads into the motor cooling circuit 1 again between the refrigerator line branching point 3 and the cooler 4.

[0031] The heating line 15 has a shut-off valve 16, a water-cooled condenser 17, a heating circuit pump 18, an electric heater 19 and an interior space heat exchanger 20. These components are usually flowed through in the order mentioned when the heating line 15 is operated. The interior space heat exchanger 20 is arranged in an air guiding device 21, for example an air flow channel, through which air is guided into a not shown motor vehicle passenger compartment, so that the passenger compartment can be heated by means of the interior space heat exchanger 20. The flow through the heating line 15 can be allowed or prevented by means of the shut-off valve 16, wherein an intermediate position of the shut-off valve 16 is also possible.

[0032] To constitute a heating circuit 22 (shown in dashed lines), a heating return line 23 is provided which fluidically connects the downstream output of the interior space heat exchanger 20 with the upstream input of the condenser 17 with one another. A non-return valve 24 is provided in the heating return line 23 which only allows a flow in the direction from the output of the interior space heat exchanger 20 towards the input of the condenser 17. By means of the heating circuit 22 it is possible to heat the passenger compartment in such a way that the coolant circulating by means of the heating circuit pump 18 is at least heated by the electric heater 19 and the thermal energy is output to the interior space heat exchanger 20. In other operating states, the coolant is additionally or alternatively heated by the condenser 17, for example by means of waste heat from the electric energy store 11 (HVS) and / or the electric drive device 2, depending on which heat is available from these components. The waste heat of the electric drive device 2 is the waste heat generated by the operation of the electric drive device 2. This waste heat can be increased on demand by adjusting the at least one electric motor of the electric drive device 2. The shut-off valve 16 prevents a flow-through if only the heating circuit 22 is to be operated and no coolant flows from the motor cooling circuit 1 into the heating line 15 and no coolant flows from the heating line 15 into the motor cooling circuit 1.

[0033] Figure 2 A refrigeration circuit 30 of a thermal management system according to an embodiment of the application is schematically shown. The refrigeration circuit 30 comprises a water-cooled condenser 17, a chiller 8 and an air-conditioning evaporator 31 provided in an air guiding device 21. A refrigerant, such as R134a, R1234yf, R1234ze or similar, circulates through these components. The chiller 8 is a heat exchanger or heat carrier which transfers thermal energy between the refrigerant of the refrigeration circuit 30 and the coolant in the chiller line 7. For this purpose, the refrigerant and the coolant flow through the chiller 8 fluidically separated from one another. The air-conditioning evaporator 31 is a heat exchanger or heat carrier which transfers thermal energy between the refrigerant of the refrigeration circuit 30 and the air flowing in the air guiding device 21. For this purpose, the refrigerant and the air flow through the air-conditioning evaporator 31 fluidically separated from one another. The air-conditioning evaporator 31 is connected in parallel to the chiller 8 in the refrigeration circuit 30. For adjusting the cooling power of the air-conditioning evaporator 31, a self-regulating and electrically shut-off expansion valve 32 is connected upstream of the air-conditioning evaporator. An expansion valve 33 is connected upstream of the chiller 8. Both the interior space heat exchanger 20 and the air-conditioning evaporator 31 are provided within the air guiding device 21. By means of them, the passenger compartment can be heated, cooled and / or dehumidified.

[0034] Furthermore, the refrigeration circuit 30 has an electric compressor 34 by means of which the refrigerant can be compressed and conveyed. Figure 2The refrigeration circuit 30 in the HVS- chiller circuit 13 also has two internal heat exchangers 35, 36, one of which is assigned to the air conditioning evaporator 31 and the other of which is assigned to the chiller 8. The internal heat exchangers 35, 36 each have two chambers which are in thermal contact but can be flowed through fluidically separately from one another. Here, one chamber is connected upstream of the chiller or air conditioning evaporator and the other chamber is connected downstream of the chiller / air conditioning evaporator. The chambers are flowed through in opposite directions and thus constitute counterflow heat exchangers. Thus, refrigerant from the compressor which is predominantly in liquid form is flowed through the internal heat exchanger in one chamber, while refrigerant from the chiller or air conditioning evaporator which is predominantly in gaseous form is flowed through the internal heat exchanger in the other chamber. By means of the internal heat exchangers 35, 36, thermal energy is extracted from the refrigerant which is predominantly in liquid form, which leads to a higher proportion of liquefaction. This energy is supplied to the refrigerant which is predominantly in gaseous form, which leads to a higher proportion of evaporation and existence in gaseous form. This serves to increase the power and efficiency of the chiller 8 and the air conditioning evaporator 31. However, the internal heat exchangers 35, 36 are not necessarily necessary for the functioning of the refrigeration circuit 30. A non-return valve 37 or a one-way valve is provided downstream of the air conditioning evaporator 31.

[0035] Downstream of the condenser 17, the refrigeration circuit 30 branches into parallel lines, one of which leads to the air conditioning evaporator 31 and the other of which leads to the chiller 8. From this point, the internal heat exchanger 35, the expansion valve 32, the air conditioning evaporator 31, the internal heat exchanger 35, the non-return valve 37 and the compressor 34 are flowed through in this order in one line. The internal heat exchanger 36, the expansion valve 33, the chiller 8, the internal heat exchanger 36 and the compressor 34 are flowed through in this order in the other line. The parallel lines merge again upstream of the compressor 34.

[0036] Some operating modes of the thermal management system are described below.

[0037] In the cooling case in which the cooler 4 is to be used to output the thermal output of the electric drive 2 to the environment, the motor cooling circuit 1 is operated, so that the waste heat of the electric drive 2 is output to the ambient air by means of the cooler 4.

[0038] The HVS-chiller circuit 13 has been described above. In addition or alternatively, a motor-chiller circuit 14 can be in operation. By means of the motor-chiller circuit 14, the waste heat of the electric drive 2 is input into the chiller 8. This thermal energy is input into the condenser 17 via the chiller 8 and the refrigeration circuit 30 as described above. This thermal energy can then be input from the condenser 17 into the heating circuit 22 and / or the heating line 15 (so-called heat pump function). Here, depending on the waste heat of the individual components and the heating requirements, only the HVS-chiller circuit 13, only the motor-chiller circuit 14 or both can be operated.

[0039] Furthermore, an AC circuit 26 can be configured, which AC circuit flows through Figure 1 is shown in the drawing in dotted lines. In this AC circuit 26, the heating line 15, the cooler 4 and the motor circuit pump 6, in particular in this order, are flowed through in succession. Downstream of the motor circuit pump 6, the AC circuit 26 leads back into the heating line 15 again. In order to operate the AC circuit 26, the shut-off valve 16 is opened and the heating circuit pump 18 and / or the motor circuit pump 6 is operated. If the AC circuit 26 is to be operated without the electric drive 2 being flowed through, the chiller valve 3a prevents the flow-through of the electric drive 2. This operating mode serves to discharge the waste heat generated at the condenser 17 via the cooler 4 to the ambient air during cooling or air conditioning of the vehicle interior.

[0040] In addition thereto, the HVS-chiller circuit 13 can also be operated, i.e. both are activated at the same time. Here, the accumulator 11 is additionally cooled and the waste heat generated at the condenser 17 at this time is discharged via the cooler 4 to the ambient air.

[0041] In addition thereto, the motor cooling circuit 1 can also be operated in such a way that the chiller valve 3a allows the flow-through of the electric drive 2. Here, the electric drive 2 is additionally cooled and the waste heat generated at this time is discharged via the cooler 4 to the ambient air.

[0042] These operating modes are not exhaustive and the person skilled in the art is of course able to advantageously use other operating modes on the basis of the described functions and the circuit diagram of the thermal management system.

[0043] Figure 3 The heating and cooling circuits of a thermal management system according to a second embodiment of the application are schematically shown. This thermal management system can be provided in a vehicle instead of the thermal management system of the first embodiment. The thermal management system differs from the thermal management system of the first embodiment in that, in the heating line 15, an NT cooler 40 is provided upstream of the shut-off valve 16, i.e. between the branching point at which the heating line 15 branches off from the motor cooling circuit 1 and the shut-off valve 16. The NT cooler 40 is provided in front of the cooler 4 as seen in the vehicle longitudinal direction, wherein, in connection with this second embodiment, the cooler 4 assumes the function of an HT cooler. Apart from these described differences, full reference is made to the description of the first embodiment.

[0044] While the application has been illustrated and described in detail in the drawings and foregoing description, the description is to be considered exemplary and not restrictive, and the application is not to be limited to the disclosed embodiments.

[0045] List of reference signs

[0046] 1 motor cooling circuit

[0047] 2 electric drive

[0048] 3 chiller line branch point

[0049] 3a chiller valve

[0050] 4 chiller

[0051] 5 compensation vessel

[0052] 6 motor circuit pump

[0053] 7 chiller line

[0054] 8 chiller

[0055] 9 HVS pump

[0056] 10 HVS valve

[0057] 11 electric accumulator

[0058] 12 non-return valve

[0059] 13 HVS-chiller circuit

[0060] 14 motor-chiller circuit

[0061] 15 heating line

[0062] 16 shut-off valve

[0063] 17 water-cooled condenser

[0064] 18 heating circuit pump

[0065] 19 electric heater

[0066] 20 internal space heat exchanger

[0067] 21 air guiding device

[0068] 22 heating circuit

[0069] 23 heating return line

[0070] 24 non-return valve

[0071] 25 heating line branch point

[0072] 26 AC circuit

[0073] 30 refrigeration circuit

[0074] 31 air conditioning evaporator

[0075] 32 expansion valve

[0076] 33 expansion valve

[0077] 34 electric compressor

[0078] 35 heat exchanger inside

[0079] 36 heat exchanger inside

[0080] 37 check valve

[0081] 40 NT cooler

Claims

1. Thermal management system for a motor vehicle, the thermal management system comprising: - a motor cooling circuit (1) in which an electric drive (2), a chiller line branch point (3), a cooler (4) and a motor circuit pump (6) are arranged; - a chiller line (7) with a chiller (8), which chiller line branches off from the motor cooling circuit (1) at the chiller line branch point (3) and opens into the motor cooling circuit (1) at a point between the cooler (4) and the motor circuit pump (6), a chiller valve (3a) being arranged at the chiller line branch point (3); - a heating line (15) with an interior space heat exchanger (20), which heating line branches off from the motor cooling circuit (1) at a point between the motor circuit pump (6) and the electric drive (2) and opens into the motor cooling circuit (1) at a point between the chiller line branch point (3) and the cooler (4); - a motor-chiller circuit (14), in which the electric drive (2), the chiller (8) and the motor circuit pump (6) are arranged; - an HVS-chiller circuit (13) with the chiller (8) and an electric accumulator (11); and - a refrigeration circuit (30) with the chiller (8), by means of which refrigeration circuit (30) waste heat of the electric drive (2) can be input into the heating line (15) by means of the chiller (8); when only the motor-chiller circuit (14) is running and the refrigeration circuit (30) is switched on, then waste heat of the electric drive (2) can be input into the heating line (15) by means of the chiller (8) by means of the refrigeration circuit (30); when both the motor-chiller circuit (14) and the HVS-chiller circuit (13) are running and the refrigeration circuit (30) is switched on, then waste heat of the electric drive (2) and waste heat of the electric accumulator (11) can be input into the heating line (15) by means of the chiller (8) by means of the refrigeration circuit (30); and when the motor-chiller circuit (14) is running and the HVS-chiller circuit (13) is switched off and the refrigeration circuit (30) is switched off, then waste heat of the electric drive (2) can be input into the electric accumulator (11), by means of which waste heat the electric accumulator (11) can be heated.

2. The thermal management system of claim 1, wherein, The motor-chiller circuit (14) leads from the chiller (8) to the motor circuit pump (6) by bypassing the cooler (4).

3. The thermal management system of claim 1 or 2, wherein, The thermal management system comprises an AC circuit (26) with the heating line (15), the cooler (4) and the motor circuit pump (6).

4. The thermal management system of claim 1 or 2, wherein, The thermal management system comprises a heating circuit (22) with the interior space heat exchanger (20) and an electric heater (19).

5. The thermal management system of claim 1 or 2, wherein, The refrigeration circuit also has an air-conditioning evaporator (31) and a water-cooled condenser (17), the chiller (8) being able to be traversed by the refrigerant of the refrigeration circuit (30) and to be traversed by the coolant of the motor cooling circuit (1) and / or of the motor-chiller circuit (14) fluidically separated from the refrigerant of the refrigeration circuit, and the air-conditioning evaporator (31) being arranged in an air guiding device (21) by means of which air can be guided into the vehicle passenger compartment.

6. The thermal management system of claim 1 or 2, wherein, The electric drive device (2) has at least one electric motor for driving the motor vehicle.

7. The thermal management system of claim 6, wherein, The electric drive device (2) also has an inverter, a DC converter, a battery control device and / or a vehicle internal charger.

8. Motor vehicle comprising a thermal management system according to any one of claims 1 to 7.

Images