Cooling system with central valve device for an electric vehicle and electric vehicle with such a cooling system

Abstract

Cooling system (100) for an electric vehicle (200) or a hybrid vehicle with a first coolant circuit (KK1) for cooling at least one electrical and / or mechanical component (14), wherein the first coolant circuit (KK1) comprises a first coolant pump (16) and a radiator (18); a second coolant circuit (CC2) for cooling an electrical energy storage device (20), in particular a high-voltage battery, wherein the second coolant circuit (CC2) comprises a second coolant pump (22); and a third coolant circuit (KK3) for conditioning the electrical energy storage device (20), wherein the third coolant circuit (KK3) comprises a chiller (24) which is in thermal contact with a refrigeration system (26) of the electric vehicle, and an additional heating module (28); a central valve assembly (12) which is operatively connected to each coolant circuit (KK1, KK2, KK3); wherein each coolant circuit (KK1, KK2, KK3) has at least one coolant supply line (KVx) starting at the central valve assembly (12) and at least one coolant return line (KRx) ending at the central valve assembly (12), wherein the central valve assembly (12) is adjustable to several switching positions (I-VII), wherein in each switching position (I-VII) at least one coolant return line (KRx) from each coolant circuit (KK1, KK2, KK3) is connected to at least one of the coolant supply lines (KVx), wherein the central valve assembly (12) establishes the following connections in a first switching position (I): Coolant return (KR1) of the first coolant circuit (KK1) with the coolant supply (KV2) of the second coolant circuit (KK2); Coolant return (KR2) of the second coolant circuit (KK2) with a chiller coolant supply (KVC) and an auxiliary heater coolant supply (KVH) of the third coolant circuit (KK3); Coolant return (KR3) of the third coolant circuit (KK3) with the coolant supply (KV1) of the first coolant circuit (KK1).

Description

[0001] The invention relates to a cooling system for an electric vehicle or a hybrid vehicle comprising a first coolant circuit for cooling at least one electrical and / or mechanical component, wherein the first coolant circuit includes a first coolant pump and a radiator; a second coolant circuit for cooling an electrical energy storage device, in particular a high-voltage battery, wherein the second coolant circuit includes a second coolant pump; a third coolant circuit for conditioning the electrical energy storage device, wherein the third coolant circuit includes a heat exchanger, in particular a chiller, which is in thermal contact with a cooling system of the electric vehicle, and / or includes an additional heating module.

[0002] A cooling system according to the preamble of claim 1 is known from DE 10 2020 123 900 A1.

[0003] For technical background, reference is made, by way of example, to the documents DE 10 2018 111 563 A1, DE 10 2019 107 190 A1, DE 10 2015 215 164 A1 and US 2017 / 0 152 957 A1, from which various differently constructed cooling systems for motor vehicles are known.

[0004] The coolant circuits of electric vehicles typically use mixing and switching valves, each with a maximum of four ports. These valves are used to distribute the coolant flow as needed to the various components requiring cooling. The resulting coolant circuit topologies are decentralized and highly branched due to the use of different valves.

[0005] For additional functionalities or interconnections, known coolant circuits require additional valves, such as check valves. This leads to increased complexity and higher costs, particularly due to increased development and assembly efforts. Furthermore, the use of additional valves requires more installation space. Additionally, the numerous hose connections to the various valves result in higher pressure losses in the coolant circuit, leading to increased power consumption at the coolant pump and thus higher (electrical) energy consumption, which negatively impacts the range, especially in electric vehicles.

[0006] The object underlying the invention is seen as being to provide a cooling system with an improved topology in which the above disadvantages can be avoided.

[0007] This problem is solved by a cooling system with the features of claim 1 and by a motor vehicle with such a cooling system. Advantageous embodiments with expedient further developments are specified in the dependent claims.

[0008] A cooling system for an electric or hybrid vehicle is therefore proposed, with a first coolant circuit for cooling at least one electrical and / or mechanical component, wherein the first coolant circuit comprises a first coolant pump and a radiator; a second coolant circuit for cooling an electrical energy storage device, in particular a high-voltage battery, wherein the second coolant circuit has a second coolant pump; a third coolant circuit for conditioning the electrical energy storage device, wherein the third coolant circuit comprises a heat exchanger, in particular a chiller, which is in thermal contact with a refrigeration system of the electric vehicle, and / or an additional heating module; and a central valve assembly that is in operative communication with each coolant circuit. It is provided that each coolant circuit has at least one coolant supply line that begins at the central valve assembly and at least one coolant return line that ends at the central valve assembly, and that the central valve assembly is adjustable to several switching positions, wherein in each switching position at least one coolant return line from each coolant circuit is connected to at least one of the coolant supply lines.

[0009] Such a cooling system features a topology originating from the central valve assembly, thus eliminating the need for numerous individual valves. This allows for a direct connection of all components requiring cooling within the central valve assembly. This direct connection reduces pressure losses compared to conventional cooling systems, enabling higher coolant flow rates for the same power input. An electrical and / or mechanical component included in the first coolant circuit could be, for example, a drive-side component (such as an electric motor), an electric charging device, a current converter, a gearbox, or similar equipment. The radiator in question could, for instance, be a low-temperature radiator.

[0010] In this cooling system, all switching positions of the coolant circuits can be adjusted solely by adjusting the central valve assembly.

[0011] Depending on the switching position, the central valve assembly can act as a mixing valve and / or a switching valve for a given coolant circuit.

[0012] In other words, the central valve assembly is designed in such a way that many or all of the valves previously found in such cooling systems can be replaced. This reduces the complexity and number of components in the cooling system, which has a positive effect on assembly and maintenance. Furthermore, the elimination of check valves in individual pipe runs or sections also prevents noise complaints caused by a ball moving abruptly within the check valve.

[0013] In this cooling system, the first coolant circuit can have a bypass section branching off downstream from the first coolant pump and upstream from the radiator. This bypass terminates at the central valve assembly and forms a bypass coolant return for the first coolant circuit to the central valve assembly. Such a bypass section allows for a complete or partial bypass of the radiator, depending on the setting of the central valve assembly. The bypass section can act as the sole coolant return for the first coolant circuit. Alternatively, the bypass coolant return can be used in conjunction with the coolant return from the radiator, each contributing a portion of the returning coolant flow. Furthermore, the bypass section can be closed off by the central valve assembly, so that the entire coolant mass flow is routed through the radiator and its coolant return line.

[0014] In this cooling system, the first coolant circuit can have an additional section branching off downstream from the first coolant pump and upstream from the drive-side component to be cooled. This additional section terminates at the central valve assembly and forms an auxiliary coolant return for the first coolant circuit. The auxiliary coolant return can also be activated or deactivated by the central valve assembly. Furthermore, it is also possible for only a portion of the coolant to flow through the auxiliary coolant return, with the remaining portion being routed, for example, through the bypass coolant return.

[0015] In the cooling system, a first air separator connected to an expansion tank can be arranged in the first coolant circuit upstream of the first coolant pump. A compensating line can branch off from the second coolant circuit upstream of the second coolant pump and connect to the expansion tank. This allows the cooling system to be filled by adding coolant to the expansion tank, which then passes through the first air separator into the first coolant circuit. Furthermore, the compensating line in the second coolant circuit ensures reliable pressure and coolant volume equalization. When needed, coolant can be drawn from the expansion tank into the second coolant circuit via this compensating line.

[0016] In this cooling system, the third coolant circuit can have a chiller coolant supply and an auxiliary heater coolant supply, arranged parallel to each other in terms of flow direction. Depending on the switching position of the central valve assembly, these supply and supply lines can function individually or together as the coolant supply (KV3) of the third coolant circuit (KK3). This allows the coolant in the third coolant circuit to be conditioned or heated by the chiller and / or the auxiliary heater, if required during a specific operating condition of the cooling system or the electric vehicle, such as at low ambient temperatures or when starting the electric vehicle. Naturally, the coolant can also be cooled by heat exchange with the refrigerant in the chiller, thus supporting the cooling of the electrical energy storage system.

[0017] In this cooling system, the second coolant circuit can include a charging coolant supply line, which is arranged parallel to the second coolant pump in terms of flow direction. This charging coolant supply line can be used to carry coolant, particularly when the electrical energy storage device is connected to a (fast) charging station and increased cooling of the electrical energy storage device is required.

[0018] In this cooling system, the first and second coolant pumps can be connected in parallel using the central valve assembly. This allows the two coolant pumps to be connected in parallel, particularly during (fast) charging of the electrical energy storage device, in order to improve cooling of the device.

[0019] In the cooling system, the central valve assembly can establish the following connections in a first switching position, which can also be referred to as the filling position or basic position: Coolant return of the first coolant circuit with the coolant supply of the second coolant circuit; Coolant return of the second coolant circuit with the coolant supply of the third coolant circuit; Coolant return of the third coolant circuit with the coolant supply of the first coolant circuit.

[0020] In the first switching position, the central valve device can still establish the following connection: Coolant return of the second coolant circuit with the chiller coolant supply and the auxiliary heater coolant supply of the third coolant circuit.

[0021] In the cooling system, the central valve assembly can establish the following connections in a second switching position, which can also be described as cooling with separate coolant circuits: Coolant return of the first coolant circuit with the coolant supply of the first coolant circuit; Coolant return of the second coolant circuit with the coolant supply of the third coolant circuit; Coolant return of the third coolant circuit with the coolant supply of the second coolant circuit.

[0022] In the second switching position, the central valve device can further establish the following connection: Bypass coolant return of the first coolant circuit with the coolant supply of the first coolant circuit, wherein coolant from the coolant return of the first coolant circuit and the bypass coolant return are mixed or wherein coolant is only routed via the bypass coolant return.

[0023] In the cooling system, the central valve assembly can establish the following connections in a third switching position, which can also be referred to as DC-Max charging: Additional coolant return of the first coolant circuit with the charging coolant supply of the second coolant circuit; Coolant return of the second coolant circuit with the coolant supply of the third coolant circuit; Coolant return of the third coolant circuit with the coolant supply of the second coolant circuit, which is parallel to the charging coolant supply; Coolant return of the third coolant circuit with the coolant supply of the first coolant circuit.

[0024] The central valve assembly in the cooling system can be set to additional switching positions, thus enabling further operating states. The central valve assembly is therefore not limited to the three switching positions mentioned above, but includes these three and additional switching positions.

[0025] An electric vehicle can be equipped with a cooling system as described above. In particular, such a cooling system can be located in the front of the electric vehicle. For this purpose, the central valve assembly and large parts of the associated coolant circuits can be combined in a central cooling system module. It is possible that the central cooling system module is designed in such a way that only vehicle components located in different places or positions within the electric vehicle, such as the electrical energy storage system, drive components, or radiator, need to be connected to it.

[0026] Further advantages and details of the invention will become apparent from the following description of embodiments with reference to the figures. These show: Fig. 1 a simplified and schematic circuit diagram of a cooling system with a central valve device; Fig.2 an enlargement of the central valve assembly of the Fig. 1 with numbered connections; Fig. 3 in sub-figures A) and B) a first switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig. 4 in sub-figures A) and B) a second switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig. 5 in sub-figures A) and B) a third switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig.6 in sub-figures A) and B) a fourth switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig. 7 in sub-figures A) and B) a fifth switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig. 8 in sub-figures A) and B) a sixth switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig.9 in sub-figures A) and B) a seventh switching position of the central valve device in the cooling system and the connections made by means of the central valve device between respective coolant returns and coolant supplies; Fig. 10 the cooling system of the Fig. 1 with a central thermal management module.

[0027] In Fig. Figure 1 shows a simplified and schematic cooling system 100 for a motor vehicle 200 that is at least partially electrically powered. The motor vehicle 200, in particular an electric vehicle, is shown in Fig. 1 is merely indicated as a schematic rectangle around the cooling system 100.

[0028] The cooling system 100 forms a complete circuit for coolant for cooling, conditioning, or temperature control of components of the motor vehicle 200. The cooling system has a central valve assembly 12, which is also referred to as central valve 12 below.

[0029] The cooling system 100 comprises a first coolant circuit KK1 for cooling at least one electrical and / or mechanical component 14 of the motor vehicle 200. The first coolant circuit KK1 includes a first coolant pump 16 and a radiator 18. The term "electrical and / or mechanical component 14" encompasses various components, such as an electric motor (not shown) and / or a current converter (e.g., a DC / DC converter), a transmission, or the like.

[0030] The cooling system 100 further comprises a second coolant circuit KK2 for cooling an electrical energy storage device 20, in particular a high-voltage battery, wherein the second coolant circuit KK2 comprises a second coolant pump 22.

[0031] The cooling system 100 further comprises a third coolant circuit KK3 for conditioning the electrical energy storage device 20, wherein the third coolant circuit KK3 includes a heat exchanger 24, in particular a chiller, which is in thermal contact with a refrigeration system 26 of the electric vehicle, shown here only in simplified terms as a rectangle. Furthermore, an additional heating module 28 can be provided in the third coolant circuit KK3. The additional heating module 28 can, for example, be an electric auxiliary heater or a high-voltage heater.

[0032] The second coolant circuit KK2 and the third coolant circuit KK3 can also be referred to together as the so-called battery circuit.

[0033] The cooling system 100 has an expansion tank 30. The cooling system 100 can be filled with coolant via the expansion tank 30. The expansion tank 30 is connected via a pipe section 32 to an air separator 34, which is located in the first coolant circuit KK1. In the example shown, the air separator 34 is located upstream of the first coolant pump 16. When a venting procedure is performed on the cooling system, air or air bubbles can escape into the expansion tank 30 via the pipe section 32.

[0034] The first coolant circuit KK1 can have a bypass section 36 branching off downstream from the first coolant pump 16 and upstream from the radiator 18. The bypass section 36 begins at a branch 38 and ends at the central valve assembly 12. Thus, the bypass section 36 forms a so-called bypass coolant return KRB of the first coolant circuit KK1 to the central valve assembly 12.

[0035] The first coolant circuit KK1 can further comprise an additional section 40 branching off downstream from the first coolant pump 16 and upstream from the drive-side component 14 to be cooled. The additional section 40 begins at a branch 42 and ends at the central valve assembly 12. Thus, the additional section 40 forms an additional coolant return KRZ of the first coolant circuit KK1.

[0036] As can be seen from the above description of the first coolant circuit KK1, in the example shown, this circuit has a coolant supply line KV1 and a coolant return line KR1, which includes the radiator 18, starting from the central valve assembly 12. Furthermore, coolant in the first coolant circuit KK1 can also be returned to the central valve 12 via the bypass coolant return line KRB and / or the auxiliary coolant return line KRZ.

[0037] The second coolant circuit KK2 has a coolant supply line KV2 and a coolant return line KR2, which includes the electrical energy storage device 20, starting from the central valve 12. Additionally, the second coolant circuit KK2 can have a charging coolant supply line KVL, which is arranged parallel to the second coolant pump 22 in terms of flow direction. The charging coolant supply line KVL begins at the central valve 12 and ends at a branch 44 located downstream of the second coolant pump 22.

[0038] Furthermore, in the second coolant circuit KK2, an expansion line 46 branches off upstream from the second coolant pump 22, which is shown with a dashed line. The expansion line 46 leads into the expansion tank 30, so that coolant equalization or pressure equalization can take place in the cooling system 100. Air can also escape into the expansion tank 30 via the expansion line 46.

[0039] The third coolant circuit KK3 has a coolant supply line KV3 and a coolant return line KR3, starting from the central valve 12. In the example shown, the third coolant circuit KK3 comprises a chiller coolant supply line KVC and an auxiliary heater coolant supply line KVH, which are arranged parallel to each other in terms of flow direction. The two flow-parallel supply lines KVC and KVH terminate in a branch 48.

[0040] In the above, referring to the Fig.In the cooling system 100 described in Section 1, the central valve assembly 12 represents a key element that serves as the starting point for the topology of the cooling system and the coolant circuits KK1, KK2, KK3. The central valve 12 is designed and configured such that all switching positions of the coolant circuits KK1, KK2, KK3 can be set solely by adjusting the central valve assembly 12. Depending on its switching position, the central valve assembly 12 can act as a mixing valve and / or a switching valve for the respective coolant circuit KK1, KK2, KK3.

[0041] Fig. Figure 2 shows the central valve 12 in an enlarged schematic representation with numbered connections. In the example shown, the connections of the central valve assembly 12 are assigned to the supply lines KVx and return lines KRx of the respective coolant circuits KKn as follows: Connection Coolant circuit KKn KVx lead Return KRx 1 KK2 KV2 - 2 KK2 KVL - 3 KK2 - KR2 4 KK1 - KR1 5 KK1 - KRB 6 KK1 KV1 - 7 KK1 - KRZ 8 KK3 KVC / KV3 9 KK3 KVH - 10 KK3 - KR3

[0042] The numbering of the connections 1 to 10 used here as an example can, of course, be different. Furthermore, the central valve assembly 12 can also have more or fewer than the ten connections shown here as an example.

[0043] The following are, with reference to the Fig.Figures 3 to 9 describe different switching positions of the central valve assembly or the central valve 12. In the upper figure, labeled A), active flow lines are shown as solid lines, while non-flow lines are shown as dotted lines. Lines or line sections that can optionally be flowed through are shown as dashed lines. In the lower figure B), the connections between the supply and return lines of the various coolant circuits KK1, KK2, and KK3, established by the central valve assembly 12 in the respective switching position, are shown. It should be noted that intersecting lines do not represent a fluid connection. A connection provided or adjustable in the central valve assembly 12 is indicated by a black dot. The switching positions are designated with Roman numerals.

[0044] Fig.Figure 3 shows the first switching position I of the central valve 12. This switching position I can also be referred to as the basic position or initial position. In this first switching position I, the following connections are established: a) Coolant return KR1 of the first coolant circuit KK1 with the coolant supply KV2 of the second coolant circuit KK2; in the central valve 12, connections 4 and 1 are therefore connected to each other. b) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV3 (KVC) of the third coolant circuit KK3; in the central valve 12, connections 3 and 8 are therefore connected to each other. c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV1 of the first coolant circuit KK1; in the central valve 12, connections 10 and 6 are therefore connected to each other. d) Coolant return KR2 of the second coolant circuit KK2 with the auxiliary heater coolant supply KVH of the third coolant circuit KK3; in the central valve 12, connections 3 and 9 are therefore connected to each other; accordingly, the coolant flow from connection 3 within the central valve is divided or branched to connections 8 and 9.

[0045] In the first switching position I, connections 2, 5 and 7 are blocked or closed, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL, KR3 and KRZ.

[0046] In this first switching position (default position), the cooling system 100 can, for example, be filled via the expansion tank 30. Furthermore, this first switching position can also serve as a default setting, meaning that the cooling system 100 is initially operated in this setting when the cooling system or the electric vehicle is started. In this switching position I, the first coolant circuit KK1 is fluidically connected to the second coolant circuit KK2.

[0047] Fig. Figure 4 shows a second switching position II of the central valve 12. This switching position II can also be described as cooling with separate circuits. In this second switching position II, the following connections are established: a) Coolant return KR1 of the first coolant circuit KK1 with the coolant supply KV1 of the first coolant circuit; thus, connections 4 and 6 in the central valve 12 are connected to each other; b) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV3 / KVC of the third coolant circuit KK3; thus, connections 3 and 8 in the central valve 12 are connected to each other; c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV2 of the second coolant circuit KK2; thus, connections 10 and 1 in the central valve 12 are connected to each other; d) Optional: Bypass coolant return KRB of the first coolant circuit KK1 with the coolant supply KV1 of the first coolant circuit KK1, whereby coolant from the coolant return KR1 of the first coolant circuit KK1 and from the bypass coolant return KRB is mixed; in this case, connections 4 and 5 in the central valve 12 are connected to connection 6, while the other connections b) and c) can be retained. Alternatively, the entire coolant flow can also be routed only via the bypass coolant return KRB. In such a case, only connections 5 and 6 would be connected to each other, but connection 4 would be closed.

[0048] In the second switching position II, connections 2, 7 and 9 are blocked or shut off, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL, KRZ and KVH.

[0049] In switching position II, the components to be cooled are cooled in separate circuits. Drive-side components 14 are cooled by coolant that circulates only in the first coolant circuit via the first coolant pump 16. The electrical energy storage device 20 is cooled by coolant that circulates in the fluidically connected coolant circuits KK2 and KK3 via the second coolant pump 22. In this switching position II, the first coolant circuit KK1 is separated from the second coolant circuit KK2, so that the two coolant pumps 16 and 22 each operate autonomous coolant circuits.

[0050] Fig. Figure 5 shows a third switching position III of the central valve 12. This switching position III can also be referred to as DC-Max charging. In this third switching position III, the following connections are made: a) Circulation coolant return KRZ of the first coolant circuit KK1 with the charging coolant supply KVL of the second coolant circuit KK2; in the central valve 12, connections 7 and 2 are therefore connected to each other; b) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV3 / KVC of the third coolant circuit KK3; thus, connections 3 and 8 in the central valve 12 are connected to each other; c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV2 of the second coolant circuit KK2, which is parallel to the charging coolant supply KVL; thus, connections 10 and 1 are connected to each other in the central valve 12; d) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV1 of the first coolant circuit KK1; thus, in the central valve 12, connections 10 and 6 are connected to each other; e) Optional: Bypass coolant return KRB of the first coolant circuit KK1 with the coolant supply KV1 of the first coolant circuit KK1, whereby coolant from the coolant return KR3 of the third coolant circuit KK3 and the bypass coolant return KRB are mixed.

[0051] Regarding connections c) and d) described above for the third switching position III, it should be noted that the coolant mass flow within the central valve is distributed to ports 1 and 6. In the third switching position III, the two coolant pumps 16 and 22 are connected in parallel. This results in improved or increased cooling, particularly at the electrical energy storage device 20, which is especially useful during (fast) charging of the energy storage device 20. In this switching position III, the first coolant circuit KK1 is fluidically connected to the second coolant circuit KK2. In this case, coolant equalization or venting can take place, including via the expansion tank 30.

[0052] In the third switching position III, connections 4 and 9 are blocked or locked, so that the coolant remains in the corresponding pipe sections KR1 and KVH or does not flow in.

[0053] Fig. Figure 6 shows a fourth switching position IV of the central valve 12. This switching position IV can also be referred to as combined circuits. In this fourth switching position IV, the following connections are established: a) Coolant return KR1 of the first coolant circuit KK1 with the coolant supply KV2 of the second coolant circuit KK2; thus, connections 4 and 1 in the central valve 12 are connected to each other; b) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV3 / KVC of the third coolant circuit KK3; thus, connections 3 and 8 in the central valve 12 are connected to each other; c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV1 of the first coolant circuit KK1; thus, connections 10 and 6 are connected to each other in the central valve 12; d) Optional: Bypass coolant return KRB of the first coolant circuit KK1 with the coolant supply KV2 of the second coolant circuit KK2, wherein coolant from the coolant return KR1 of the first coolant circuit KK1 and the bypass coolant return KRB are mixed or wherein coolant is only routed via the bypass coolant return KRB.

[0054] In the fourth switching position IV, connections 2, 7 and 9 are blocked or shut off, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL, KRZ and KVH.

[0055] In this switching position IV, the first coolant circuit KK1 is fluidically connected to the second coolant circuit KK2. In this case, coolant equalization or venting can take place, including via the expansion tank 30.

[0056] Fig.Figure 7 shows a fifth switching position V of the central valve 12. This switching position V can also be referred to as battery heating. In this fifth switching position V, the following connections are made: a) Bypass coolant return KRB of the first coolant circuit KK1 with the coolant supply KV1 of the first coolant circuit KK1; thus, connections 5 and 6 in the central valve 12 are connected to each other; b) Coolant return KR2 of the second coolant circuit KK2 with the auxiliary heater coolant supply KVH of the third coolant circuit KK3; in the central valve 12, connections 3 and 9 are therefore connected to each other; c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV2 of the second coolant circuit KK2; thus, in the central valve 12, connections 10 and 1 are connected to each other; d) Optional: Coolant return KR1 of the first coolant circuit KK1 with the coolant supply KV1, so that the coolant volume flow is divided between the coolant return KR1 and the bypass coolant return KRB.

[0057] In the fifth switching position V, connections 2, 4, 7 and 8 are blocked or closed, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL, KR1, KRZ and KVC.

[0058] In switching position V, coolant can be heated in the third coolant circuit by means of the auxiliary heater 28. The heated coolant then flows into the second coolant circuit KK2, where it can transfer heat to the electrical energy storage device 20, thus tempering or conditioning it. In this switching position V, the first coolant circuit KK1 is separated from the second coolant circuit KK2, so that the two coolant pumps 16, 22 each operate autonomous coolant circuits.

[0059] Fig. Figure 8 shows a sixth switching position VI of the central valve 12. This switching position VI can also be referred to as heat pump operation. In this sixth switching position VI, the following connections are made: a) Bypass coolant return KRB of the first coolant circuit KK1 with the (chiller) coolant supply KV3 / KVC of the third coolant circuit KK3; in the central valve 12, connections 5 and 8 are therefore connected to each other; b) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV2 of the second coolant circuit KK2; thus, connections 3 and 1 in the central valve 12 are connected to each other; c) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV1 of the first coolant circuit KK1; in the central valve 12, connections 10 and 6 are therefore connected to each other.

[0060] In the sixth switching position VI, connections 2, 4, 7 and 9 are blocked or closed, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL, KR1, KRZ and KVH.

[0061] In switching position VI, the coolant in the area of ​​the drive-side component(s) 14 in the first coolant circuit KK1 absorbs heat. The heated coolant flows bypassing the radiator 18 via the bypass coolant return KRB into the third coolant circuit KK3 and there into the chiller 24. In the chiller 24, the coolant transfers heat to the refrigerant of the refrigeration system 26 of the vehicle 200. The chiller 24 therefore operates as a water-to-water heat pump for the refrigeration system 26. In this switching position VI, the first coolant circuit KK1 is separated from the second coolant circuit KK2, so that the two coolant pumps 16, 22 each operate autonomous coolant circuits.

[0062] Fig.Figure 9 shows a seventh switching position VII of the central valve 12. This switching position VII can also be referred to as the excess heat function. In this seventh switching position VII, the following connections are established: a) Coolant return KR1 of the first coolant circuit KK1 with the (chiller) coolant supply KV3 / KVC and the auxiliary heater coolant supply KVH of the third coolant circuit KK3; in the central valve 12, connections 4 and 8, 9 are connected to each other. b) Bypass coolant return KRB of the first coolant circuit KK1 with the (chiller) coolant supply KV3 / KVC and the auxiliary heater coolant supply KVH of the third coolant circuit KK3; in the central valve 12, connections 5 and 8, 9 are therefore connected to each other; c) Coolant return KR2 of the second coolant circuit KK2 with the coolant supply KV2 of the second coolant circuit KK2; thus, connections 3 and 1 in the central valve 12 are connected to each other; d) Coolant return KR3 of the third coolant circuit KK3 with the coolant supply KV1 of the first coolant circuit KK1; in the central valve 12, connections 10 and 6 are therefore connected to each other.

[0063] In the seventh switching position VII, connections 2 and 7 are blocked or locked, so that the coolant is stagnant or does not flow into the corresponding pipe sections KVL and KRZ.

[0064] In switching position VII, the coolant circulates primarily in cooling circuits KK1 and KK3, with coolant circuit KK2 operating separately. In the so-called excess heat function, the coolant in cooling circuits KK1 and KK3 is circulated in such a way that heat can be dissipated from the system to the environment, potentially via the vehicle's refrigeration system. In this mode, the coolant can absorb or release heat, particularly in the area of ​​the chiller 24 in the third cooling circuit KK3, and absorb heat in the area of ​​the auxiliary heater 28. In this switching position VII, the first cooling circuit KK1 is separated from the second cooling circuit KK2, so that the two coolant pumps 16 and 22 each operate autonomous coolant circuits.

[0065] Fig. 10 shows the cooling system 100 of the Fig.Figure 1, where a so-called central thermal management module 300 is shown hatched. The components of the cooling system 100 located under the hatching can be grouped or integrated into the module 300. Such a central thermal management module 300 can be provided as a modular component, so that it only needs to be connected to the radiator 18, the electrical energy storage unit 20, and the drive-side components 14. This reduces the effort required for assembling a motor vehicle 200.

[0066] The central valve assembly 12 used in the cooling system 100 presented here can have a structure as described, for example, in the simultaneously filed applications DE 10 2021 109 739 A1 entitled "Central valve assembly with rotatable adjusting element for a cooling system of a motor vehicle, cooling system and electric vehicle with such a cooling system" and DE 10 2021 109 742 A1 entitled "Central valve assembly with connection grid and rotatable adjusting element for a cooling system of a motor vehicle and electric vehicle with such a cooling system". Reference is made in particular to the content of these two applications with regard to the internal structure and the resulting switching positions within the central valve assembly 12.

Claims

[1] Cooling system (100) for an electric vehicle (200) or a hybrid vehicle with a first coolant circuit (KK1) for cooling at least one electrical and / or mechanical component (14), wherein the first coolant circuit (KK1) comprises a first coolant pump (16) and a radiator (18); a second coolant circuit (CC2) for cooling an electrical energy storage device (20), in particular a high-voltage battery, wherein the second coolant circuit (CC2) comprises a second coolant pump (22); and a third coolant circuit (KK3) for conditioning the electrical energy storage device (20), wherein the third coolant circuit (KK3) comprises a chiller (24) which is in thermal contact with a refrigeration system (26) of the electric vehicle, and an additional heating module (28); a central valve assembly (12) which is operatively connected to each coolant circuit (KK1, KK2, KK3); wherein each coolant circuit (KK1, KK2, KK3) has at least one coolant supply line (KVx) starting at the central valve assembly (12) and at least one coolant return line (KRx) ending at the central valve assembly (12), wherein the central valve assembly (12) is adjustable to several switching positions (I-VII), wherein in each switching position (I-VII) at least one coolant return line (KRx) from each coolant circuit (KK1, KK2, KK3) is connected to at least one of the coolant supply lines (KVx), wherein the central valve assembly (12) establishes the following connections in a first switching position (I): Coolant return (KR1) of the first coolant circuit (KK1) with the coolant supply (KV2) of the second coolant circuit (KK2); Coolant return (KR2) of the second coolant circuit (KK2) with a chiller coolant supply (KVC) and an auxiliary heater coolant supply (KVH) of the third coolant circuit (KK3); Coolant return (KR3) of the third coolant circuit (KK3) with the coolant supply (KV1) of the first coolant circuit (KK1). [2] Cooling system (100) according to claim 1, wherein all switching positions (I-VII) of the coolant circuits (KK1, KK2, KK3) can be adjusted solely by adjusting the central valve assembly (12). [3] Cooling system (100) according to claim 2, wherein the central valve device (12) acts as a mixing valve and / or switching valve for a respective coolant circuit (KK1, KK2, KK3) depending on the switching position (I-VII). [4] Cooling system (100) according to one of the preceding claims, wherein the first coolant circuit (KK1) has a bypass section (36) branching downstream from the first coolant pump (16) and upstream from the radiator (18), which terminates at the central valve assembly (12) and forms a bypass coolant return (KRB) of the first coolant circuit (KK1) to the central valve assembly (12). [5] Cooling system (100) according to one of the preceding claims, wherein the first coolant circuit (KK1) has an additional section (40) branching downstream from the first coolant pump (16) and upstream from the drive-side component (14) to be cooled, which terminates at the central valve assembly (12) and forms an additional coolant return (KRZ) of the first coolant circuit (KK1). [6] Cooling system (100) according to one of the preceding claims, wherein in the first coolant circuit (KK1) upstream of the first coolant pump (16) a first air separation device (34) is arranged which is connected to an expansion tank (30). [7] Cooling system (100) according to claim 6, wherein in the second coolant circuit (KK2) upstream of the second coolant pump (22) an expansion line (46) branches off, which is connected to the expansion tank (30). [8] Cooling system (100) according to one of the preceding claims, wherein the third coolant circuit (KK3) comprises the chiller coolant supply (KVC) and the auxiliary heater coolant supply (KVH), which are arranged parallel to each other in terms of flow and which, depending on the switching position of the central valve device (12), individually or jointly form the function of the coolant supply (KV3) of the third coolant circuit (KK3). [9] Cooling system (100) according to one of the preceding claims, wherein the second coolant circuit (KK2) has a charging coolant supply line (KVL) which is arranged in a flow-technical manner parallel to the second coolant pump (22). [10] Cooling system (100) according to one of the preceding claims, wherein the first coolant pump (16) and the second coolant pump (22) can be connected in parallel to each other in terms of flow by means of the central valve device (12). [11] Cooling system (100) according to one of the preceding claims, wherein the central valve device (12) establishes the following connections in a second switching position (II): Coolant return (KR1) of the first coolant circuit (KK1) with the coolant supply (KV1) of the first coolant circuit (KK1); Coolant return (KR2) of the second coolant circuit (KK2) with the coolant supply (KV3, KVC) of the third coolant circuit (KK3); Coolant return (KR3) of the third coolant circuit (KK3) with the coolant supply (KV2) of the second coolant circuit (KK2). [12] Cooling system (100) according to claim 11, wherein the central valve device (12) establishes the following connection in the second switching position (II): Bypass coolant return (KRB) of the first coolant circuit (KK1) with the coolant supply (KV1) of the first coolant circuit (KK1), where coolant from the coolant return (KR1) of the first coolant circuit (KK1) and the bypass coolant return (KRB) are mixed, or where coolant is only routed via the bypass coolant return (KRB). [13] Cooling system (100) according to claim 8, wherein the central valve device (12) establishes the following connections in a third switching position (III): Additional coolant return (KRZ) of the first coolant circuit (KK1) with the charging coolant supply (KVL) of the second coolant circuit (KK2); Coolant return (KR2) of the second coolant circuit (KK2) with the coolant supply (KV3, KVC) of the third coolant circuit (KK3); Coolant return (KR3) of the third coolant circuit (KK3) with the coolant supply (KV2) of the second coolant circuit (KK2) which is parallel to the charging coolant supply (KVL); Coolant return (KR3) of the third coolant circuit (KK3) with the coolant supply (KV1) of the first coolant circuit (KK1). [14] Electric vehicle (200) with a cooling system (100) according to one of the preceding claims.

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