Heat pump arrangement with a chiller for battery-powered vehicles and method for operating the heat pump arrangement

Abstract

Heat pump arrangement with a chiller (9) for battery-powered vehicles - comprising a refrigerant circuit with a compressor (1), a heating condenser (2), a refrigerant valve with expansion function (3), an ambient heat exchanger (4), at least one evaporator (6) with associated refrigerant valve with expansion function (5) and a 3 / 2-way refrigerant valve with expansion function (8) arranged parallel to the evaporator (6) with a refrigerant path via a chiller bypass (29) and a refrigerant path via a chiller (9), wherein - an ambient heat exchanger bypass (28) with a refrigerant valve with expansion function (10) is arranged between the heating condenser (2) and the refrigerant valve with expansion function (3) in front of the chiller (9) and - comprising a battery coolant circuit (24) with a coolant pump (17), the chiller (9), a battery heat exchanger (19) and a battery cooling radiator (13), wherein - a battery cooling radiator bypass (30) with a coolant auxiliary heater (21) is arranged in parallel to the battery cooling radiator (13) via a 3 / 2-way coolant valve (20) in the battery coolant circuit (24) and - comprising a powertrain coolant circuit (25) with a coolant pump (16), a powertrain cooler (15) and a powertrain cooling radiator (12), wherein - a fluid connection from the powertrain coolant circuit (25) to the battery coolant radiator bypass (30) of the battery coolant circuit (24) is formed parallel to the powertrain cooling radiator (12) and - that a battery heat exchanger bypass (32) with a 3 / 2-way coolant valve (18) is provided to connect the powertrain coolant circuit (25) with the chiller (9) of the battery coolant circuit (24).

Description

[0001] The invention relates to a heat pump arrangement with a chiller for battery-powered vehicles.

[0002] Furthermore, the invention relates to methods for operating the heat pump arrangement in selected operating modes, wherein the refrigerant circuit of the heat pump arrangement also includes the cooling of the cabin and thus represents a combined heat pump and refrigeration system.

[0003] The invention is applicable to electrically powered vehicles, which typically use high-voltage batteries (HV batteries) as energy storage devices to supply power to the vehicle's drivetrain. Further applications of the invention include vehicles with so-called plug-in hybrids, which produce only small amounts of waste heat and whose batteries are integrated into a thermal management system.

[0004] An efficient heat supply for the vehicle, combined with optimal thermal management of the battery and the electric powertrain, plays an important role in this.

[0005] Electric battery-powered vehicles generate relatively little waste heat, and therefore there is a regular need to efficiently generate heat for heating the vehicle cabin and to provide it in sufficient quantity and at an appropriate temperature level.

[0006] In the prior art, refrigerant circuits for refrigeration systems and heat pump circuits are known for this configuration, which are specifically tailored to battery-powered vehicles.

[0007] For example, DE 10 2019 109 796 A1 discloses a heat flow management device and a method for operating a heat flow management device which has a refrigerant circuit and a drive train coolant circuit as well as a heating train heat transfer fluid circuit.

[0008] DE 10 2016 100 971 A1 relates to a climate control system for a vehicle with a heat pump subsystem and DE 10 2008 062 176 A1 discloses a device and a method for temperature control of electrical elements of a motor vehicle.

[0009] US patent 2019 / 0344640 A1 describes a thermal management device for a vehicle, which includes a heat pump.

[0010] DE 10 2020 111 505 A1 relates to a heat pump arrangement for battery-powered vehicles and a method for operating a heat pump arrangement, wherein several chillers are required to couple the refrigerant circuit and the heat transfer circuit in order to utilize the waste heat of the vehicle.

[0011] Furthermore, a vehicle air conditioning system is known from JP 2019-206 215 A. This system provides a vehicle air conditioning system in which, if the target cooling temperature differs between several cooled devices, the respective target cooling temperature can be achieved in a simple manner.It comprises a first heat transfer circuit in which a first heat transfer fluid flows, absorbing heat emitted by a battery; a second heat transfer circuit in which a second heat transfer fluid flows, absorbing heat emitted by an electric motor; a first heat transfer fluid heat exchanger, which, through heat exchange between a refrigerant flowing in a refrigerant circuit and the first heat transfer fluid flowing in the first heat transfer circuit, causes heat to be transferred from the first heat transfer fluid to the refrigerant; and a second heat transfer fluid heat exchanger, which is connected in the refrigerant circuit on a downstream side of the first heat transfer fluid heat exchanger in the refrigerant circuit and, through heat exchange between the refrigerant flowing in the refrigerant circuit and the second heat transfer fluid flowing in the second heat transfer circuit, causes heat to be transferred from the second heat transfer fluid to the first heat transfer fluid.

[0012] Furthermore, a cooling system is derived from JP 2019-182 135 A and another vehicle air conditioning system from JP 2013-189 118 A.

[0013] However, these systems are often very complex and rarely able to combine the needs and requirements of the vehicle occupants for adequate heat supply via the vehicle's air conditioning system, also known as the climate control unit, with the optimal cooling or heating of the battery and electric powertrain required in the various operating states.

[0014] The object of the invention is to provide a heat pump arrangement for battery-powered vehicles which combines increased efficiency of the heat pump for supplying the air conditioning system with heat for the passenger compartment of the motor vehicle with the possibility of optimal heat supply to the battery, which includes not only efficient cooling but also heating required in certain operating conditions.

[0015] The heat pump arrangement within a thermal management system for battery-powered electric vehicles is designed to enable flexible operation under a wide range of operating and environmental conditions. The operation of the vehicle, and consequently the thermal management system, is affected by various factors, including environmental and driving conditions, user comfort requirements, component functionality of the battery, electric powertrain, and control units, as well as safety considerations. Therefore, a reliable, vehicle-wide thermal management system and a heat pump arrangement are necessary to ensure the operation of vehicle components within a permissible temperature range while simultaneously providing comfort features such as cabin climate control.Furthermore, the thermal systems must ensure the safe operation of the vehicle, for example by defrosting and dehumidifying the windshield to achieve a fog-free appearance.

[0016] The problem is solved by heat pump arrangements and methods with the features of the independent patent claims. Further developments are specified in the dependent patent claims.

[0017] The object of the invention is achieved in particular by a heat pump arrangement with a chiller for battery-powered vehicles, which has a refrigerant circuit and two coolant circuits, a battery coolant circuit and a powertrain coolant circuit. The refrigerant circuit has at least one compressor, a heating condenser, a refrigerant valve with expansion function associated with an ambient heat exchanger, at least one evaporator with an associated refrigerant valve with expansion function, and a 3 / 2-way refrigerant valve with expansion function arranged parallel to the evaporator, with one refrigerant path via a chiller bypass and one refrigerant path via a chiller connected on the refrigerant side.

[0018] Between the heating condenser and the refrigerant valve with expansion function arranged downstream, an ambient heat exchanger bypass with a refrigerant valve with expansion function is arranged upstream of the chiller.

[0019] The battery coolant circuit includes a coolant pump, a chiller connected to the coolant side, a battery heat exchanger and a battery cooling radiator, wherein a battery cooling radiator bypass with a coolant auxiliary heater is arranged in the battery coolant circuit in parallel to the battery cooling radiator via a 3 / 2-way coolant valve.

[0020] The powertrain coolant circuit includes a coolant pump, a powertrain cooler and a powertrain cooling radiator, with a fluid connection to the battery cooler radiator bypass of the battery coolant circuit running parallel to the powertrain cooling radiator.

[0021] Furthermore, a battery heat exchanger bypass with a 3 / 2-way coolant valve is arranged in the battery coolant circuit, which also forms a direct connection between the powertrain coolant circuit and the chiller.

[0022] The functionalities of 3 / 2-way valves can also be achieved with individual components. However, this leads to significantly higher costs.

[0023] An air-based PTC condenser is advantageously placed in the vehicle's air conditioning system in addition to the heating condenser for warming the air for the vehicle cabin.

[0024] An advantageous embodiment of the heat pump arrangement consists in a drive train loop with a 3 / 2-way coolant valve being configured parallel to the drive train cooling radiator. Furthermore, the drive train loop is advantageously arranged parallel to the fluid connection with the battery coolant circuit.

[0025] Advantageously, the ambient heat exchanger, the powertrain cooling radiator and the battery cooling radiator are combined in one radiator unit.

[0026] Furthermore, it is advantageous to arrange a refrigerant collector in front of the compressor in the refrigerant circuit and preferably to use R134a or R1234yf as the refrigerant in the refrigerant circuit.

[0027] For the purposes of the invention, a heating condenser is understood to be a heat exchanger that transfers heat within the vehicle's air conditioning system to the airflow of the air conditioning system for heating the vehicle cabin. An ambient heat exchanger is provided that, in heat pump operation of the arrangement, absorbs heat from the ambient air as a radiator, or, in refrigeration system operation, transfers heat to the ambient air.

[0028] A chiller is a heat exchanger that is integrated into the refrigerant circuit on one side and the coolant circuit on the other, with the chiller supplying cold to the battery heat exchanger and the powertrain cooler on the coolant side and releasing heat on the refrigerant side.

[0029] The refrigerant collector is also called an accumulator and can optionally also be designed and operated as a separator for liquid refrigerant in front of the compressor.

[0030] A bypass is a refrigerant line that bypasses a component of the refrigerant circuit or directs part of the refrigerant mass flow parallel to the component in question.

[0031] The vehicle's coolant circuits are thermally coupled to the refrigerant circuit via the chiller and usually contain a water-glycol mixture, which functions as a coolant or heat transfer fluid depending on the operating state of the entire system.

[0032] The low-temperature coolers are coolant coolers designed as radiators that dissipate heat into the ambient air. The battery heat exchanger absorbs waste heat from the battery within the coolant circuit and dissipates it to ensure optimal battery operation. The powertrain cooler also absorbs heat from the powertrain components to cool them. Powertrain components include, for example, electronic components that generate waste heat, as well as the electric motor itself.

[0033] Active cooling refers to cooling using a refrigerant circuit, whereas passive cooling refers to cooling using radiators with heat being released into the environment.

[0034] The concept of the invention consists in the thermal management system of a battery-powered electric vehicle linking various heat sources and sinks via both refrigerant and coolant circuits using the heat pump arrangement according to the invention. In general, the operation of the system is highly flexible to enable efficient, powerful, and dynamic operation of all components and to ensure situation-dependent cooling or heating of the various vehicle components.

[0035] Depending on the vehicle application, thermal system architectures can differ significantly, for example, regarding the inclusion of heat pump functionality. Generally, more flexible systems allow for more versatile and efficient heat transfer between vehicle components. However, this added efficiency and performance typically comes at the cost of increased system complexity and associated system costs.

[0036] A key aspect in designing a thermal management system is the structure of the refrigerant circuit, including the number of heat exchangers connecting the refrigerant system to the coolant circuits. Generally, the most efficient system designs feature a dual-chiller layout with two separate heat exchangers in addition to the evaporator in the air path of the air conditioner, connected to different coolant circuits. This allows for parallel operation of both coolant circuits, providing maximum flexibility. However, such a layout increases the complexity of the refrigerant system, particularly on the (low-pressure) suction side. This results in higher pressure drops, which negatively impacts system efficiency and reduces the COP (Coefficient of Performance). Furthermore, the complex circuitry leads to increased package and system costs.

[0037] Furthermore, thermal management systems must ensure sufficient cabin heating and cooling capacity under all operating conditions, both steady-state and highly transient. While heat pump system architectures generally allow the use of various onboard heat sources, such as the environment, powertrain, battery, processor units, and the like, these sources are sometimes insufficient, particularly during highly transient operation and periods of significant heating.

[0038] A critical operating scenario is, for example, starting a vehicle at very low ambient temperatures with a cold cabin and battery. To ensure rapid heating of the cabin and battery, modern thermal management systems include auxiliary electric heating elements, such as low- or high-voltage PTCs (positive temperature coefficient thermistors), which can be installed in both the coolant circuit and the cabin air path. This technology is primarily used in non-heat pump systems, where cabin air is typically heated exclusively by air-source PTCs. However, heat pump systems are also frequently supplemented with air-source PTCs for comfort reasons, due to higher heating capacity and improved system dynamics. Air-source PTCs, however, significantly increase the overall system costs.

[0039] According to the invention and the independent claims, two novel system architectures are derived as heat pump arrangements, enabling flexible, high-performance, and efficient operation of a thermal management system. Both heat pump arrangements allow for a reduction in the necessary components, thus streamlining the system architecture and the associated system costs. One embodiment further allows for the elimination of the high-voltage PTC in the air path, resulting in a further significant reduction in overall system costs.

[0040] Further details, features, and advantages of embodiments of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. These show: Fig. 1: Heat pump layout flow diagram, Fig. 2: Flowchart of cabin cooling with the cabin as the heat source and the environment as the heat sink, Fig. 3: Flowchart of cabin cooling and active battery cooling with the cabin and battery as heat source and the environment as heat sink, Fig. 4: Flowchart of cabin cooling and passive battery cooling with the cabin and battery as heat source and the environment as heat sink, Fig. 5: Flowchart of cabin reheat and active battery cooling with the cabin and battery as heat source and the environment as heat sink, Fig. 6: Flowchart of the cabin reheat process with the environment and the battery as heat sources and the cabin as heat sink, Fig. 7: Flowchart of the reheat cabin with the environment and the auxiliary heater as heat sources and the cabin as heat sink, Fig. 8: Flowchart of the reheat cabin with the environment and the auxiliary heater as heat sources and the cabin as heat sink, Fig. 9: Flowchart of cabin heating with the environment as the heat source and the cabin as the heat sink, Fig. 10: Flowchart of cabin heating with the environment and the powertrain as heat sources and the cabin and the battery as heat sinks, Fig. 11: Flowchart of cabin heating with the environment and the drivetrain as heat sources and the cabin as heat sink, Fig. 12: Flowchart of cabin heating with the drivetrain as the heat source and the cabin as the heat sink, Fig. 13: Heat pump arrangement with drive train loop, Fig. 14: Flowchart of cabin heating with the drivetrain and auxiliary heater as heat source and the cabin as heat sink, Fig. 15: Flowchart of cabin heating with the auxiliary heater as the heat source and the cabin as the heat sink and Fig. 16: Flow diagram of defrosting ambient heat exchanger with the auxiliary heater as heat source and the cabin as heat sink.

[0041] The heat pump arrangement according to Fig. 1 consists of a central refrigerant circuit and two low-temperature cooling circuits: one for cooling / heating the battery (battery coolant circuit 24) and the other for cooling / heating the electric powertrain (powertrain coolant circuit 25). Cabin air conditioning is provided via the refrigerant circuit. The system can be integrated into any vehicle with a standard air conditioning architecture.

[0042] The refrigerant circuit of the thermal management system is represented by a double line and, in addition to the evaporator 6 in the air path to the cabin, is based on a single refrigerant heat exchanger, the chiller 9, which is connected to several expansion valves 8, 10. For maximum efficiency in heating mode, the system has a direct heat exchanger in the air path for the vehicle cabin air 34 of the air conditioning unit 27, the heating condenser 2. The system is preferably designed for operation with refrigerants such as R134a and R1234yf. In the vehicle's air conditioning unit 27, the vehicle cabin air 34 is conditioned. In a broader sense, this includes, depending on the requirements, the cooling, heating, and dehumidification of the air introduced into the vehicle cabin from the air conditioning unit 27.

[0043] The system architecture enables flexible operation of the heat pump system in various operating modes such as cooling, heating, and dehumidification with minimal use of expansion and directional valves, utilizing multiple heat sources and sinks. These heat sources and sinks include the environment, the high-voltage battery, the electric powertrain with its electrical and electronic components, the high-voltage air PTC, and the refrigerant heater.

[0044] Within the refrigerant circuit, the compressor 1 is connected to the heating condenser 2 integrated in the air conditioner 27. From the heating condenser 2, the refrigerant can be routed via a refrigerant expansion valve (EXV) 3 to the ambient heat exchanger (OHX) 4. The refrigerant expansion valve 3 between the heating condenser 2 and the ambient heat exchanger 4 allows for the adjustment of different pressure levels between these two components. This function is required to regulate heat transfer to the ambient air 26 in cooling mode and heat absorption from the ambient air 26 in heating mode. In this way, the overall system can be operated at three different pressure levels, with the intermediate pressure level varying between the high-pressure and suction pressure levels.

[0045] As an alternative to the connection via the ambient heat exchanger 4, the heating condenser 2 is also connected to a refrigerant valve with expansion function (EXV) 10 at the inlet to the chiller 9 via the ambient heat exchanger bypass 28.

[0046] In cooling mode, the refrigerant is passed through the ambient heat exchanger 4 to dissipate the heat of condensation into the environment. In heating mode, the heat of condensation is released in the heating condenser 2 to heat the vehicle cabin air 34, which is then conditioned in the air conditioning unit 27.

[0047] The outlet of the ambient heat exchanger 4 is connected to both a refrigerant expansion valve 5 at the inlet to the evaporator 6 and a 3 / 2-way refrigerant expansion valve 8. The 3 / 2-way refrigerant expansion valve 8 has three ports, labeled 1, 2, and 3. Ports 2 and 3 are outlets, and port 1 is an inlet. While the expansion side of the refrigerant valve 8 is connected to the chiller 9 at outlet 2, outlet 1 provides a direct connection to the system's suction side, to the refrigerant receiver 11 and the compressor 1, via a bypass line designated as chiller bypass 29. Alternatively, individual valves with the corresponding functionalities can be used instead of the 3 / 2-way refrigerant expansion valve 8.

[0048] The suction-side refrigerant lines from the outlet of the evaporator 6, the chiller 9, and the chiller bypass 29 are preferably connected to each other before the inlet to the refrigerant receiver 11. The outlet of the refrigerant receiver 11 is connected to the suction side of the compressor 1. With this configuration, refrigerant can be partially evaporated, fully evaporated, and superheated in the ambient heat exchanger 4, in the evaporator 6 of the air conditioning unit 27, and in the chiller 9.

[0049] The specific system layout of the refrigerant circuit allows for the parallel operation of the ambient heat exchanger 4 and the chiller 9 at different pressure levels. If required, the ambient heat exchanger 4 and chiller 9 can also be operated in series mode. The operating mode can be flexibly adapted to the ambient and operating conditions, such as temperatures and heat sources within the vehicle.

[0050] The battery coolant circuit 24 is shown in a dashed line and is connected to the refrigerant circuit via the chiller 9. At the outlet of the chiller 9, the coolant is directed via a 3 / 2-way coolant valve 18 either to the battery heat exchanger 19 for cooling the high-voltage battery or via a parallel bypass line, the battery heat exchanger bypass 32. At the outlet of the battery heat exchanger 19, another 3 / 2-way coolant valve 20 directs the coolant towards the battery cooling radiator 13 of the battery coolant circuit 24 or, via the battery cooling radiator bypass 30, towards the optional electric coolant auxiliary heater 21, which is used, for example, for battery heating. The coolant is circulated by a coolant pump 17 at the inlet to the chiller 9, which is connected to both the battery cooling radiator 13 and the optional coolant auxiliary heater 21.

[0051] The powertrain coolant circuit 25 is represented by a solid line and is used to cool the electric powertrain via the powertrain radiator 15. At the outlet of the powertrain radiator 15 of the electric powertrain, a 3 / 2-way coolant valve 14 directs the coolant to the powertrain cooling radiator 12. The powertrain cooling radiator 12 is connected to the coolant pump 16, which is located at the inlet to the powertrain radiator 15. In this way, the powertrain coolant circuit 25 can be used for passive cooling of the electric powertrain, enabling efficient system operation. If the heat from the powertrain is to be utilized, the powertrain coolant circuit 25 can be connected to the battery coolant circuit 24 via the 3 / 2-way coolant valve 14, which is schematically indicated by the connection to the battery cooling radiator bypass 30 of the battery coolant circuit 24.

[0052] Additional cabin heating capacity can be achieved by using an air-side PTC heating element 7 in the air conditioning unit 27.

[0053] The radiators of the heat pump arrangement, the drive train cooling radiator 12, the battery cooling radiator 13 and the ambient heat exchanger 4 are preferably structurally combined in a radiator unit 31.

[0054] In Fig. 2 is mode 1 cabin cooling through highlighted components of the heat pump arrangement. Fig. Figure 1 shows that inactive components or refrigerant or coolant lines are shown in thin lines, and active refrigerant or coolant lines are shown in relatively thicker lines.

[0055] The switching state of the valves is represented in the following figures by the symbols. If the triangle symbols are shown only as an outline and empty, the valve is open. If the triangle symbols are completely filled, the valves are closed. If the valves are operated with the expansion function, where provided, the triangles are shown hatched. The in Fig. Mode 2 shown is designed for high ambient temperatures of more than 30 °C.

[0056] In this mode, the refrigerant flows from compressor 1 through the air-cooled ambient heat exchanger (OHX) 4, releasing heat of condensation to the environment. The refrigerant flow is expanded into the evaporator 6 by the EXV 5 located upstream of the evaporator 6 to cool the air 34 flowing through the evaporator 6 into the cabin. The refrigerant valve 3 is set to maximum flow without expansion, and the heating condenser 2 of the air conditioning unit 27 is switched off, so that the refrigerant circuit delivers its entire cooling capacity to the air 34 to be cooled in the vehicle cabin.

[0057] The battery coolant circuit 24 operates in recirculation mode to homogenize the battery's temperature distribution. Chiller 9 is not in operation; the corresponding refrigerant valves are closed, so that chiller 9 is inoperative in this mode with regard to heat transfer and only coolant flows through it. The coolant flows from coolant pump 17, through chiller 9, through battery heat exchanger 19, and through battery radiator bypass 30 back to coolant pump 17. Coolant auxiliary heater 21 is not in operation in this mode and is inoperative with regard to heat transfer.

[0058] The coolant of the powertrain coolant circuit 25 of the electric powertrain is guided by the coolant pump 16 via the powertrain cooler 15 and the powertrain cooling radiator 12 as a radiator and is passively cooled by the ambient air 26.

[0059] In Fig. 3 shows mode 2 cabin cooling and active battery cooling.

[0060] This mode is used at high ambient temperatures above 30 °C.

[0061] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, releasing heat of condensation to the ambient air 26. A partial flow of the refrigerant is expanded into the evaporator 6 by the EXV 5 located upstream of the evaporator 6, in order to cool the air 34 flowing into the cabin through the evaporator 6 of the air conditioner 27, analogous to mode 1. The refrigerant valve 3 is switched without expansion function, and the heating condenser 2 is also inactive.

[0062] The other partial flow of refrigerant after the ambient heat exchanger (OHX) 4 is expanded in the 3 / 2-way refrigerant valve with expansion function 8 and evaporated in the chiller 9, absorbing heat from the battery coolant circuit 24 to cool the battery, and subsequently combined with the partial flow of refrigerant from the evaporator via a refrigerant collector 11 to the compressor 1.

[0063] The battery coolant circuit 24 operates in active cooling mode to cool the battery. The coolant absorbs heat from the battery in the battery heat exchanger 19 and is then actively cooled in the chiller 9 by the refrigerant circuit, transferring heat to the refrigerant circuit. For this purpose, as described above, a partial flow of the refrigerant is routed parallel to the evaporator 6 via the 3 / 2-way refrigerant valve with expansion function (EXV) 8 and expands at the inlet to the chiller 9. The coolant flows from the coolant pump 17 via the chiller 9 through the battery heat exchanger 19 and the battery cooler radiator bypass 30 back to the coolant pump 17. The coolant auxiliary heater 21 is not in operation in this mode and has no function with regard to heat transfer.

[0064] The coolant of the powertrain coolant circuit 25 of the electric powertrain is operated analogously to the operating mode according to Fig. 2 from the coolant pump 16 via the powertrain cooler 15 and the powertrain cooling radiator 12 as a radiator and passively cooled by the ambient air 26.

[0065] In Fig. Figure 4 shows the cabin cooling and passive battery cooling mode at high ambient temperatures above 30 °C.

[0066] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, releasing heat of condensation to the ambient air 26. The refrigerant flow is expanded into the evaporator 6 by the refrigerant expansion valve (EXV) 5 located upstream of the evaporator 6, in order to cool the vehicle cabin air 34 flowing through the evaporator 6. The refrigerant valve 3 is set to maximum flow without expansion, and the heating condenser 2 of the air conditioning unit 27 is switched off, so that the refrigerant circuit delivers its entire cooling capacity to the air 34 to be cooled in the vehicle cabin.

[0067] The battery coolant circuit 24 operates in passive cooling mode to cool the battery via the battery heat exchanger 19. The coolant flows from the coolant pump 17 through the chiller 9 to the battery heat exchanger 19, absorbs heat from the battery, and is then cooled in the battery cooling radiator 13, transferring heat to the ambient air 26. The chiller 9 is not in operation; the relevant refrigerant valves are closed.

[0068] The electric powertrain is passively cooled via the powertrain coolant circuit 25 through the powertrain cooling radiator 12, analogous to the procedure according to Fig. 2 and Fig. 3.

[0069] In Fig. 5 represents the Reheat Cabin mode and active battery cooling at relatively mild ambient temperatures above 15 °C.

[0070] In vehicle air conditioning, a reheat mode means that the air 34 supplied to the vehicle cabin is first cooled and dehumidified in the air conditioning unit 27 and then heated to a desired temperature. Reducing the humidity of the vehicle cabin air 34 reduces or prevents the vehicle windows from fogging up.

[0071] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, releasing heat of condensation to the ambient air 26. The heat transfer to the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 located before the refrigerant enters the ambient heat exchanger (OHX) 4. The refrigerant is expanded to a medium pressure level within the ambient heat exchanger (OHX) 4.

[0072] The refrigerant flow is expanded into the evaporator 6 by the refrigerant expansion valve (EXV) 5 located upstream of the evaporator 6, in order to cool the air 34 flowing through the evaporator 6 into the cabin. Subsequently, the cabin air 34 is reheated by the heating condenser 2 of the air conditioning unit 27. The heat flow required to reheat the cabin airflow is less than the heat flow extracted from the airflow in the evaporator 6. The heat extraction from the air 34 described above, the possible moisture removal from the air 34, and the subsequent heating of the air 34 to the desired cabin temperature are referred to as reheating.

[0073] The battery coolant circuit 24 operates in passive cooling mode to cool the battery. The coolant absorbs heat from the battery via the battery heat exchanger 19 and is then cooled in the battery cooling radiator 13, transferring heat to the ambient air 26. The chiller 9 is not in operation, and the corresponding refrigerant valves are closed. The electric powertrain is passively cooled via the powertrain cooling radiator 12 of the powertrain coolant circuit 25.

[0074] The operating mode of the battery coolant circuit 24 and the powertrain coolant circuit 25 corresponds to the requirements for Fig. 4 described circuits and procedures.

[0075] In Fig. 6 represents the Reheat Cabin mode at low ambient temperatures above 0 °C.

[0076] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the environment to the refrigerant. The refrigerant is thereby evaporated or partially evaporated. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger 4. The refrigerant is expanded to a medium pressure level within the ambient heat exchanger 4. Prior to this, heat is transferred from the refrigerant to the airflow for cabin air conditioning via the heating condenser 2, and the vehicle cabin air 34 is additionally heated by the air PTC 7. The air PTC 7 is an auxiliary heat exchanger for heating the cabin air based on the principle of PTC thermistors. These are also known as PTC resistors or PTC thermistors. Alternatively, other auxiliary heat exchangers can be used to heat the vehicle cabin air 34.

[0077] Downstream, a partial flow of the refrigerant is expanded through the refrigerant valve with expansion function 5, located upstream of the evaporator 6, to cool the air 34 flowing through the evaporator 6 into the cabin. Subsequently, the cabin air 34 is reheated by the heating condenser 2. The air PTC 7 can be active to assist in reheating the cabin supply air. The heat flow required to reheat the cabin airflow is greater, and in particular much greater, than the heat flow extracted from the airflow in the evaporator 6.

[0078] In parallel, a partial flow of refrigerant is expanded into the chiller 9 via the 3 / 2-way refrigerant valve with expansion function (EXV) 8, which is located upstream of the chiller 9. To increase system performance, heat from the electric powertrain is transferred from the powertrain cooler 15, and optionally from the battery heat exchanger 19, to the refrigerant via the chiller 9. For this purpose, the battery coolant circuit 24 operates in active cooling mode and is connected to the powertrain coolant circuit 25. In the mode shown, the coolant absorbs heat from the battery and the powertrain and transfers this heat to the refrigerant circuit, where it is used to heat the vehicle cabin via the heating condenser 2.

[0079] The battery coolant circuit 24 and the powertrain coolant circuit 25 are connected, and the coolant flows in a circuit from the coolant pump 17 via the chiller 9, the battery heat exchanger 19, the 3 / 2-way coolant valve 20, the coolant pump 16, and the powertrain cooler 15 to the coolant pump 17. The radiators of the coolant circuits, the powertrain cooling radiator 12, and the battery cooling radiator 13 are not operated in this mode.

[0080] In Fig. 7 represents the Reheat Cabin mode at low ambient temperatures above 0 °C.

[0081] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the ambient air 26 to the refrigerant. The refrigerant is thereby evaporated or partially evaporated. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger (OHX) 4. The refrigerant is expanded to a medium pressure level within the ambient heat exchanger (OHX) 4. Prior to this, heat is transferred from the refrigerant to the airflow for cabin air conditioning via the heating condenser 2, causing the refrigerant to condense. Additionally, the vehicle cabin air 34 is heated by the air PTC 7.

[0082] Downstream, a partial flow of the refrigerant is expanded through the refrigerant valve with expansion function 5, located upstream of the evaporator 6, to cool the air 34 flowing through the evaporator 6 into the cabin. Subsequently, the cabin air 34 is reheated by the heating condenser 2. The air PTC 7 can be active to assist in reheating the cabin air 34. The heat flow required to reheat the cabin air is greater than the heat flow extracted from the airflow in the evaporator 6.

[0083] In parallel, a partial flow of refrigerant is expanded into the chiller 9 through the 3 / 2-way refrigerant valve with expansion function (EXV) 8 located upstream of the chiller 9. To increase system performance, the electric auxiliary heater, the coolant heater 21, is active in the battery radiator bypass 30 of the battery coolant circuit 24. Heat is transferred from the coolant heater 21 to the coolant circuit and then via the chiller 9 to the refrigerant, bypassing the battery heat exchanger 19. The coolant of the battery coolant circuit 24 flows from the chiller 9 through the 3 / 2-way coolant valve 18, through the battery heat exchanger bypass 32 with the coolant heater 21, to the coolant pump 17, and then back to the chiller 9 in the circuit.

[0084] In Fig. 8 represents the Reheat Cabin mode at low ambient temperatures above 0 °C.

[0085] In this mode, a partial flow of refrigerant passes through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the environment to the refrigerant. The refrigerant is thereby evaporated or partially evaporated. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger (OHX) 4. Prior to this, heat is transferred from the refrigerant to the vehicle cabin air 34 for cabin air conditioning via the heating condenser 2, causing the refrigerant to condense. Additionally, the air 34 for the vehicle cabin is heated by the air PTC 7.

[0086] Downstream, the refrigerant is expanded into the evaporator 6 by the refrigerant valve with expansion function 5, located upstream of the evaporator 6, in order to cool the air 34 flowing through the evaporator 6 into the cabin. Subsequently, the cabin air 34 is reheated by the heating condenser 2. The air PTC 7 can be active to assist in reheating the cabin supply air. The heat flow required to reheat the cabin airflow is significantly greater than the heat flow extracted from the cabin air 34 in the evaporator 6.

[0087] In parallel, the remaining partial flow of refrigerant is diverted to the ambient heat exchanger (OHX) 4 via the ambient heat exchanger bypass 28 upstream of the refrigerant expansion valve (EXV) 3 and expanded via the single refrigerant expansion valve (EXV) 10 upstream of the chiller 9. This configuration allows heat absorption at different pressure and / or temperature levels. The refrigerant paths to the ambient heat exchanger (OHX) 4 / evaporator 6 and to the chiller 9 operate in parallel. To increase system performance, the electric auxiliary heater, the coolant heater 21, is active in the battery cooler radiator bypass 30 of the battery coolant circuit 24. Heat is transferred from the coolant heater 21 to the coolant circuit and then via the chiller 9 to the refrigerant, without passing through the battery heat exchanger 19.The coolant flows in a circuit from the coolant pump 17 via the chiller 9, the 3 / 2-way coolant valve 18 and the battery heat exchanger bypass 32 via the coolant auxiliary heater 21 to the coolant pump 17 of the battery coolant circuit 24.

[0088] In Fig. 9 shows the cabin heating mode with the ambient heat source at low / cold ambient temperatures down to -20 °C.

[0089] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the environment to the refrigerant. The refrigerant evaporates in the process. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger (OHX) 4. Prior to this, heat is transferred from the refrigerant to the vehicle cabin air 34 via the heating condenser 2 for cabin air conditioning, causing the refrigerant to condense. Additionally, the vehicle cabin air 34 can be heated by the air PTC 7.

[0090] In this mode, the ambient heat exchanger (OHX) 4 is the only heat source for cabin heating, unless the air PTC 7 is operated.

[0091] To maximize system efficiency, the refrigerant is routed around the chiller 9 via the chiller bypass 29 using the 3 / 2-way refrigerant valve with expansion function (EXV) 8, so that the chiller 9 is switched off on the refrigerant side in this mode and the expansion function in the 3 / 2-way refrigerant valve with expansion function (EXV) 8 is not active.

[0092] The battery coolant circuit 24 is directly connected to the powertrain coolant circuit 25 via a 3 / 2-way coolant valve 18, bypassing the battery heat exchanger 19 by means of the battery heat exchanger bypass 32. The coolant flows from the coolant pump 17 through the non-functional chiller 9, the 3 / 2-way coolant valve 18, the battery heat exchanger bypass 32, the coolant pump 16, the powertrain radiator 15, and the 3 / 2-way coolant valve 14 to the coolant pump 17. This homogenizes the temperature distribution of the powertrain. No heat is dissipated via the radiators of the coolant circuits.

[0093] In Fig. 10 is the cabin heating mode with ambient heat as the heat source at low / cold ambient temperatures down to -20 °C.

[0094] In this mode, the refrigerant flows through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the environment to the refrigerant. The refrigerant evaporates in the process. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger (OHX) 4. Prior to this, heat is transferred from the refrigerant to the airflow for cabin air conditioning via the heating condenser 2, causing the refrigerant to condense. Additionally, the vehicle cabin air 34 can be heated by means of the air PTC 7.

[0095] The ambient heat exchanger (OHX) 4 is the sole heat source for cabin heating when the air PTC 7 is not active. The expansion function in the 3 / 2-way refrigerant expansion valve (EXV) 8 is not active in this mode.

[0096] To maximize system efficiency, the refrigerant is routed around the chiller 9 via the chiller bypass 29 using the 3 / 2-way refrigerant expansion valve (EXV) 8, so that the chiller 9 is switched off on the refrigerant side in this mode.

[0097] The battery coolant circuit 24 is directly connected to the powertrain coolant circuit 25 via a 3 / 2-way coolant valve 20, with the coolant flow passing through the battery heat exchanger 19. The coolant flows from the coolant pump 17 via the non-functional chiller 9, the battery heat exchanger 19, the 3 / 2-way coolant valve 20, the coolant pump 16, and the powertrain radiator 15 to the coolant pump 17. This transfers heat from the powertrain to the battery and homogenizes the temperature distribution in the powertrain and battery.

[0098] In Fig. 11 shows the cabin heating mode with ambient heat and drivetrain waste heat as heat sources at low / cold ambient temperatures down to -20 °C.

[0099] In this mode, a partial flow of refrigerant passes through the air-cooled ambient heat exchanger (OHX) 4, transferring heat from the environment to the refrigerant. The refrigerant is thereby evaporated or partially evaporated. The heat absorption from the ambient air 26 is controlled by the refrigerant expansion valve (EXV) 3 before it enters the ambient heat exchanger (OHX) 4. To maximize system efficiency, the refrigerant is routed around the chiller 9 via the chiller bypass 29 using the 3 / 2-way expansion valve (EXV) 8, effectively shutting down the chiller 9 in this mode.

[0100] In parallel, the remaining partial flow of refrigerant is diverted to the ambient heat exchanger (OHX) 4 via the ambient heat exchanger bypass 28 before the refrigerant expansion valve (EXV) 3 and expanded via the single refrigerant expansion valve (EXV) 10 before the chiller 9. This configuration allows heat absorption at different pressure and / or temperature levels. The refrigerant paths to the ambient heat exchanger (OHX) 4 / evaporator 6 and to the chiller 9 are operated in parallel.

[0101] The battery coolant circuit 24 is directly connected to the powertrain coolant circuit 25, bypassing the battery heat exchanger 19. The coolant flows from the coolant pump 17 via the chiller 9, the 3 / 2-way coolant valve 18, the battery heat exchanger bypass 32, the coolant pump 16, the powertrain cooler 15, and the 3 / 2-way coolant valve 14 to the coolant pump 17. This transfers heat from the powertrain coolant circuit 25 to the refrigerant circuit via the chiller 9.

[0102] The heat sources for heating the cabin supply air, which is done by the heating condenser 2, are therefore the ambient air 26 and the waste heat from the powertrain. The air PTC 7 can be active to assist in heating the vehicle cabin air 34.

[0103] In Fig. 12 is the cabin heating mode with the heat source being the waste heat from the drivetrain at low / cold ambient temperatures down to -20 °C.

[0104] To maximize system performance and efficiency, in this mode the entire refrigerant mass flow is diverted to the ambient heat exchanger (OHX) 4 via the ambient heat exchanger bypass 28 upstream of the refrigerant expansion valve (EXV) 3 and expanded via the single refrigerant expansion valve (EXV) 10 upstream of the chiller 9. This achieves a complete refrigerant-side isolation of the external ambient heat exchanger (OHX) 4. As a result, the system suction pressure can be significantly increased.

[0105] The coupled coolant circuits 24 and 25 are as follows: Fig. As described in section 11, the battery coolant circuit 24 is directly connected to the powertrain coolant circuit 25 by means of the 3 / 2-way coolant valve 18 and the battery heat exchanger bypass 32, bypassing the battery heat exchanger 19. This allows heat to be transferred from the powertrain coolant circuit 25 to the refrigerant circuit via the chiller 9.

[0106] The powertrain is therefore the primary heat source for heating the vehicle cabin air 34, which is done by the heating condenser 2. The air PTC 7 can be active to assist in reheating the cabin supply air.

[0107] In Fig. 13 the heat pump arrangement according to Fig. 1. Advantageously furthered education.

[0108] In contrast to the circuit of the components in Fig. 1 is the circuit according to Fig. 13 after the evaporator 6 in the direction of refrigerant flow, supplemented by a check valve 23 in the refrigerant circuit, before the chiller bypass 29 and the refrigerant-side outlet of the chiller 9 are combined with the outlet from the evaporator 6.

[0109] Furthermore, the circuit is as follows: Fig. 13 no air PTC 7 according to Fig. 1 is provided for additional heating of the vehicle cabin air 34.

[0110] Additionally, a drive train loop 33 with a 3 / 2-way coolant valve 22 is provided.

[0111] The heat pump arrangement according to Fig. 13 consists of a central refrigerant circuit and two low-temperature cooling circuits: one for cooling / heating the battery (battery coolant circuit 24) and the other for cooling / heating the electric powertrain (powertrain coolant circuit 25). Cabin air conditioning is provided via the refrigerant circuit. The system can be integrated into any vehicle with a standard air conditioning architecture.

[0112] The heat pump arrangement according to Fig. 13 also allows the omission of the high-voltage air PTC in the air path of the air conditioning unit 27 in contrast to the arrangement according to Fig. 1. The system enables the use of the coolant heating of the battery coolant circuit 24 by means of the coolant auxiliary heater 21 and the provision of heat for the cabin heating via the heat pump function.

[0113] The refrigerant circuit of the thermal management system according to Fig. 13 is based, in addition to the evaporator 6 in the air path to the cabin, on a single refrigerant heat exchanger, the chiller 9, which is connected to several expansion valves 8, 10, analogous to the design according to Fig. 1. For maximum efficiency in heating mode, the system has a direct heat exchanger in the air path of the air conditioner 27, the heating condenser 2. The system is preferably designed for operation with refrigerants such as R134a and R1234yf.

[0114] The system architecture also allows for flexible operation of the heat pump system in various operating modes such as cooling, heating, and dehumidification with minimal use of expansion and directional valves, utilizing multiple heat sources and sinks. These heat sources and sinks include the environment, the high-voltage battery, the electric drivetrain with its electrical and electronic components, and the coolant heater.

[0115] Within the refrigerant circuit, the compressor 1 is connected to the heating condenser 2 integrated into the air conditioner. From the heating condenser 2, the refrigerant can be routed via a refrigerant expansion valve (EXV) 3 to the ambient heat exchanger (OHX) 4. The refrigerant expansion valve 3 between the heating condenser 2 and the ambient heat exchanger 4 allows for the adjustment of different pressure levels between these two components. This function is required to regulate heat transfer to the ambient air 26 in cooling mode and heat absorption from the ambient air 26 in heating mode. In this way, the overall system can operate at three different pressure levels, with the intermediate pressure level varying between the high-pressure and suction pressure levels.

[0116] As an alternative to the connection via the ambient heat exchanger 4, the heating condenser 2 is also connected to a refrigerant valve with expansion function (EXV) 10 at the inlet to the chiller 9 via the ambient heat exchanger bypass 28.

[0117] In cooling mode, the refrigerant is passed through the ambient heat exchanger 4 to dissipate the heat of condensation into the environment. In heating mode, the heat of condensation is released in the heating condenser 2 to heat the vehicle cabin air 34, which is then conditioned in the air conditioning unit 27.

[0118] The outlet of the ambient heat exchanger 4 is connected to both a refrigerant expansion valve 5 at the inlet to the evaporator 6 and a 3 / 2-way refrigerant expansion valve 8. The 3 / 2-way refrigerant expansion valve 8 has three ports, designated 1, 2, and 3. Ports 2 and 3 are outlets, and port 1 is an inlet. While the expansion side of the 3 / 2-way refrigerant valve 8 is connected to the chiller 9 at outlet 2, outlet 1 provides a direct connection to the suction side of the system, to the refrigerant receiver 11 and the compressor 1, via a bypass line designated as chiller bypass 29. A check valve 23 is integrated into the chiller bypass 29. Instead of the 3 / 2-way refrigerant valve with expansion function 8, individual valves with the corresponding functionalities can also be used.

[0119] The suction-side refrigerant lines from the outlet of the evaporator 6, the chiller 9, and the chiller bypass 29 are preferably connected to each other before the inlet to the refrigerant receiver 11. The outlet of the refrigerant receiver 11 is connected to the suction side of the compressor 1. With this configuration, refrigerant can be partially evaporated, fully evaporated, and superheated in the ambient heat exchanger 4, in the evaporator 6 of the air conditioning unit 27, and in the chiller 9.

[0120] The specific system layout of the refrigerant circuit allows for the parallel operation of the ambient heat exchanger 4 and the chiller 9 at different pressure levels. If required, the ambient heat exchanger 4 and chiller 9 can also be operated in series. The operating mode can be flexibly adapted to the ambient and operating conditions, such as temperatures and heat sources within the vehicle.

[0121] The battery coolant circuit 24 is connected to the refrigerant circuit via the chiller 9. At the outlet of the chiller 9, the coolant is directed via a 3 / 2-way coolant valve 18 either to the battery heat exchanger 19 for cooling the high-voltage battery or via a parallel bypass line, the battery radiator bypass 30. At the outlet of the battery heat exchanger 19, another 3 / 2-way coolant valve 20 directs the coolant towards the battery radiator 13 of the battery coolant circuit 24 or towards the electric coolant auxiliary heater 21. The coolant is circulated by a coolant pump 17 at the inlet to the chiller 9, which is connected to both the battery radiator 13 and the coolant auxiliary heater 21.

[0122] The powertrain coolant circuit 25 is used to cool the electric powertrain via the powertrain radiator 15. At the outlet of the powertrain radiator 15 of the electric powertrain, a 3 / 2-way coolant valve 14 directs the coolant to the powertrain cooling radiator 12. The powertrain cooling radiator 12 is connected to the coolant pump 16, which is located at the inlet to the powertrain radiator 15. In this way, the powertrain coolant circuit 25 can be used for passive cooling of the electric powertrain, enabling efficient system operation. If the heat from the powertrain is to be utilized, the powertrain coolant circuit 25 can be connected to the battery coolant circuit 24 via the 3 / 2-way coolant valve 14, which is schematically indicated by the connection to the battery cooling radiator bypass 30 of the battery coolant circuit 24.

[0123] Additionally, coolant can be recirculated through the drivetrain via the drivetrain loop 33 using a 3 / 2-way coolant valve 22. The two 3 / 2-way coolant valves 14 and 22 can also be combined in a 4 / 2-way coolant valve.

[0124] The heat pump arrangement according to Fig. The 13 feasible modes are identical to those in the Fig. 2 to 12 illustrated modes of the heat pump arrangement according to Fig. 1, wherein the modes described on the following pages according to the Fig. 14 to 16 for the heat pump arrangement according to Fig. 13 more will be added.

[0125] In Fig. 14 shows the cabin heating mode with the heat sources of the waste heat from the powertrain and the heat from the coolant auxiliary heater 21 at low / cold ambient temperatures down to -20 °C.

[0126] To maximize system performance and efficiency, the entire refrigerant mass flow is routed through the heating condenser 2, where superheat and condensation heat are transferred to the vehicle cabin air 34 for cabin air conditioning. The refrigerant then condenses and, prior to the refrigerant expansion valve (EXV) 3, is diverted to the ambient heat exchanger (OHX) 4 via the ambient heat exchanger bypass 28. It is then routed through the single refrigerant expansion valve (EXV) 10, where it expands, and evaporates in the chiller 9 before being fed to the compressor 1. This ensures complete refrigerant isolation of the external ambient heat exchanger (OHX) 4.

[0127] This allows the suction pressure of the system to be significantly increased even at very low ambient temperatures.

[0128] The coupled coolant circuits 24 and 25 are as follows: Fig. 11 and Fig. 12 described and executed. In contrast to these circuits, the coolant auxiliary heater 21 is actively operated and heats the coolant.

[0129] The battery coolant circuit 24 is directly connected to the powertrain coolant circuit 25, bypassing the battery heat exchanger 19, via the 3 / 2-way coolant valve 18 and the battery heat exchanger bypass 32. This allows heat from the powertrain coolant circuit 25 and the coolant auxiliary heater 21 to be transferred to the refrigerant circuit via the chiller 9. The powertrain recirculation loop 33 is deactivated in this mode.

[0130] The powertrain and the coolant auxiliary heater 21 are therefore the primary heat sources for heating the vehicle cabin air 34, which is done by the heating condenser 2. The use of an air PTC condenser is not required.

[0131] In Fig. 15 shows the cabin heating mode with the coolant auxiliary heater 21 as the heat source at low / cold ambient temperatures down to -20 °C.

[0132] To maximize system performance and efficiency, the entire refrigerant mass flow in this mode, analogous to the mode from Fig. The refrigerant is diverted to the ambient heat exchanger (OHX) 4 via the ambient heat exchanger bypass 28 upstream of the refrigerant expansion valve (EXV) 3 and expanded via the single refrigerant expansion valve (EXV) 10 upstream of the chiller 9. This achieves a complete refrigerant-side isolation of the external ambient heat exchanger (OHX) 4.

[0133] This allows the suction pressure of the system to be significantly increased even at very low ambient temperatures.

[0134] The battery coolant circuit 24 is not connected to the powertrain coolant circuit by bypassing the battery heat exchanger 19 via the 3 / 2-way coolant valve 18 and the battery heat exchanger bypass 32. The auxiliary coolant heater 21 serves as the heat source. Thus, the heat from the auxiliary coolant heater 21 is transferred from the battery coolant circuit 24 to the refrigerant circuit via the chiller 9.

[0135] The recirculation circuit is active in this mode and ensures a homogenization of the temperature distribution of the powertrain by switching a short circuit via the coolant pump 16, the powertrain cooler 15, the 3 / 2-way coolant valve 22 and the powertrain loop 33.

[0136] The coolant heater 21 is the sole heat source for heating the cabin supply air, which is done by the heating condenser 2. The use of an air PTC condenser is therefore unnecessary.

[0137] In Fig. Figure 16 shows the ambient heat exchanger (OHX) 4 defrosting mode at low / cold ambient temperatures down to -20 °C.

[0138] To defrost the ambient heat exchanger (OHX) 4, in this mode the refrigerant flows unthrottled through the refrigerant valve 3 after the compressor 1 and the heating condenser 2, and under high pressure and temperature through the air-cooled ambient heat exchanger (OHX) 4, whereby the heat of condensation is used to defrost the ambient heat exchanger (OHX) 4 and finally released to the ambient air 26. The refrigerant expansion valve (EXV) 3 does not throttle the refrigerant mass flow in this mode.

[0139] The refrigerant is then expanded into the chiller 9 via the 3 / 2-way refrigerant valve with expansion function (EXV) 8 located upstream of the chiller 9, where it evaporates. In this mode, the system's suction pressure can be significantly increased even at very low ambient temperatures.

[0140] The battery coolant circuit 24 is also in this mode as in Fig. As described in section 15, the battery heat exchanger 19 is bypassed by means of the 3 / 2-way coolant valve 18 and the battery heat exchanger bypass 32 and is not connected to the powertrain coolant circuit 25. The coolant auxiliary heater 21 serves as the heat source. Thus, the heat from the coolant auxiliary heater 21 is transferred from the battery coolant circuit 24 to the refrigerant circuit via the chiller 9.

[0141] The powertrain loop 33 of the powertrain coolant circuit 25 is as follows: Fig.15 is also active in this mode and ensures a homogenization of the temperature distribution of the powertrain by switching a short circuit via the coolant pump 16, the powertrain cooler 15, the 3 / 2-way coolant valve 22 and the powertrain loop 33.

[0142] The heating of the vehicle cabin air 34 is carried out exclusively by the heating condenser 2. The use of an air PTC can be dispensed with. Reference symbol list 1 compressor 2 heating capacitor 3 Refrigerant valve with expansion function (EXV) 4 ambient heat exchangers (OHX) 5 Refrigerant valve with expansion function (EXV) / evaporator 6 evaporators 7 Air PTC 8 3 / 2-way refrigerant valve with expansion function (EXV) 9 Chiller 10 Refrigerant valve with expansion function (EXV) 11 refrigerant collectors 12 Powertrain cooling radiator of the powertrain coolant circuit 13 Battery cooling radiator of the battery coolant circuit 14 3 / 2-way coolant valve 15 powertrain coolers 16 Coolant pump 17 Coolant pump 18 3 / 2-way coolant valve 19 battery heat exchangers 20 3 / 2-way coolant valve 21 Coolant auxiliary heater 22 3 / 2-way coolant valve 23 Check valve 24 Battery coolant circuit for cooling the HV battery 25 Powertrain coolant circuit for cooling the electric powertrain 26 Ambient air 27 Air conditioner 28 Ambient heat exchanger bypass 29 Chiller Bypass 30 battery cooler radiator bypass 31 Radiator unit 32 Battery heat exchanger bypass 33 Powertrain loop 34 Vehicle cabin air

Claims

[1] Heat pump arrangement with a chiller (9) for battery-powered vehicles - comprising a refrigerant circuit with a compressor (1), a heating condenser (2), a refrigerant valve with expansion function (3), an ambient heat exchanger (4), at least one evaporator (6) with associated refrigerant valve with expansion function (5) and a 3 / 2-way refrigerant valve with expansion function (8) arranged parallel to the evaporator (6) with a refrigerant path via a chiller bypass (29) and a refrigerant path via a chiller (9), wherein - an ambient heat exchanger bypass (28) with a refrigerant valve with expansion function (10) is arranged between the heating condenser (2) and the refrigerant valve with expansion function (3) in front of the chiller (9) and - comprising a battery coolant circuit (24) with a coolant pump (17), the chiller (9), a battery heat exchanger (19) and a battery cooling radiator (13), wherein - a battery cooling radiator bypass (30) with a coolant auxiliary heater (21) is arranged in parallel to the battery cooling radiator (13) via a 3 / 2-way coolant valve (20) in the battery coolant circuit (24) and - comprising a powertrain coolant circuit (25) with a coolant pump (16), a powertrain cooler (15) and a powertrain cooling radiator (12), wherein - a fluid connection from the powertrain coolant circuit (25) to the battery coolant radiator bypass (30) of the battery coolant circuit (24) is formed parallel to the powertrain cooling radiator (12) and - that a battery heat exchanger bypass (32) with a 3 / 2-way coolant valve (18) is provided to connect the powertrain coolant circuit (25) with the chiller (9) of the battery coolant circuit (24). [2] Heat pump arrangement according to claim 1, characterized by , that an air PTC (7) is arranged in an air conditioning unit (27) in addition to the heating condenser (2) for heating the air for the vehicle cabin. [3] Heat pump arrangement according to claim 1, characterized by , that a drive train loop (33) with a 3 / 2-way coolant valve (22) is formed parallel to the drive train cooling radiator (12). [4] Heat pump arrangement according to one of claims 1 to 3, characterized by , that the ambient heat exchanger (4), the powertrain cooling radiator (12) and the battery cooling radiator (13) are combined in a radiator unit (31). [5] Heat pump arrangement according to any one of claims 1 to 4, characterized by, that a refrigerant collector (11) is arranged in front of the compressor (1) in the refrigerant circuit. [6] Heat pump arrangement according to any one of claims 1 to 5, characterized by that R134a or R1234yf is used as the refrigerant in the refrigerant circuit. [7] Method for operating a heat pump arrangement according to one of claims 1 to 6 for actively cooling the vehicle cabin, for homogenizing the temperature distribution of the battery and for passively cooling the powertrain at ambient temperatures above 30 °C, characterized by, that the refrigerant condenses after the compressor (1) in the ambient heat exchanger (4), expands in the refrigerant valve with expansion function (5) and evaporates in the evaporator (6) absorbing heat from the air to cool the vehicle cabin and is directed to the compressor (1), wherein the battery coolant circuit (24) is operated in recirculation mode with the coolant pump (17), the battery heat exchanger (19) and the battery cooler radiator bypass (30) without heating or cooling and the powertrain coolant circuit (25) with the coolant pump (16), the powertrain cooler (15) and the powertrain cooler radiator (12) for passive cooling. [8] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for actively cooling the vehicle cabin, for actively cooling the battery and for passively cooling the powertrain at ambient temperatures above 30 °C, characterized by, that the refrigerant is condensed in the ambient heat exchanger (4) after the compressor (1) and subsequently a partial flow is expanded in the refrigerant valve with expansion function (5) and evaporated in the evaporator (6) absorbing heat from the air to cool the vehicle cabin and is directed to the compressor (1) and a partial flow is expanded in the 3 / 2-way refrigerant valve with expansion function (8) and evaporated in the chiller (9) absorbing heat from the battery coolant circuit (24) to cool the battery and is directed to the compressor (1), wherein the battery coolant circuit (24) is operated in active cooling mode with the coolant pump (17), the chiller (9) and the battery heat exchanger (19) and the battery cooler radiator bypass (30) without heating and the powertrain coolant circuit (25) with the coolant pump (16), the powertrain cooler (15) and the powertrain cooler radiator (12) for passive cooling. [9] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for actively cooling the vehicle cabin, passively cooling the battery and passively cooling the powertrain at ambient temperatures above 30 °C, characterized by , that the refrigerant condenses after the compressor (1) in the ambient heat exchanger (4), expands in the refrigerant valve with expansion function (5) and evaporates in the evaporator (6) absorbing heat from the air to cool the vehicle cabin and is directed to the compressor (1), wherein the battery coolant circuit (24) is operated by the coolant pump (17) via the non-functional chiller (9), the battery heat exchanger (19) and the battery cooling radiator (13) for passive cooling and the powertrain coolant circuit (25) with the coolant pump (16), the powertrain cooler (15) and the powertrain cooling radiator (12) for passive cooling. [10] Method for operating a heat pump arrangement according to one of claims 1 to 6 for the reheat mode of the vehicle cabin, for passive cooling of the battery and for passive cooling of the powertrain at ambient temperatures of more than 15 °C, characterized by, that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is subsequently expanded to a medium pressure level in the refrigerant valve with expansion function (3) and releases heat in the ambient heat exchanger (4), is expanded to a low pressure level in the refrigerant valve with expansion function (5) and is evaporated in the evaporator (6) by absorbing heat from the air and is directed to the compressor (1), wherein the battery coolant circuit (24) is operated by the coolant pump (17) via the non-functional chiller (9), the battery heat exchanger (19) and the battery cooling radiator (13) for passive cooling and the powertrain coolant circuit (25) with the coolant pump (16), the powertrain cooler (15) and the powertrain cooling radiator (12) for passive cooling. [11] Method for operating a heat pump arrangement according to one of claims 1 to 6 for the reheat mode of the vehicle cabin, for active cooling of the battery and for active cooling of the powertrain at ambient temperatures above 0°C, characterized bythat the refrigerant releases heat in the heating condenser (2) after the compressor (1), is subsequently expanded to a medium pressure level in the refrigerant expansion valve (3) and absorbs heat in the ambient heat exchanger (4), and subsequently a partial flow is expanded in the refrigerant expansion valve (5) and evaporates in the evaporator (6) by absorbing heat from the air and is directed to the compressor (1), and a partial flow is expanded in the 3 / 2-way refrigerant expansion valve (8) and evaporates in the chiller (9) by absorbing heat from the battery coolant circuit (24) and from the powertrain coolant circuit (25) and is directed to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other and the coolant is pumped by the coolant pump (17) via the chiller (9), the battery heat exchanger (19), the 3 / 2-way refrigerant valve (20), the coolant pump (16)the powertrain cooler (15) flows to the coolant pump (17). [12] Method for operating a heat pump arrangement according to one of claims 1 to 6 for the reheat mode of the vehicle cabin at ambient temperatures above 0 °C, characterized by, that the refrigerant releases heat in the heating condenser (2) after the compressor (1), is subsequently expanded to a medium pressure level in the refrigerant valve with expansion function (3) and absorbs heat in the ambient heat exchanger (4), and subsequently a partial flow is expanded in the refrigerant valve with expansion function (5) and evaporates in the evaporator (6) absorbing heat from the air and is directed to the compressor (1), and a partial flow is expanded in the 3 / 2-way refrigerant valve with expansion function (8) and evaporates in the chiller (9) absorbing heat from the battery coolant circuit (24) and is directed to the compressor (1), wherein in the battery coolant circuit (24) the coolant flows from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18) and the battery heat exchanger bypass (32) via the coolant auxiliary heater (21) to the coolant pump (17), wherein the coolant auxiliary heater (21) is operated. [13] Method for operating a heat pump arrangement according to one of claims 1 to 6 for the reheat mode of the vehicle cabin at ambient temperatures above 0 °C, characterized bythat the refrigerant releases heat in the heating condenser (2) after the compressor (1), subsequently a partial flow is expanded to a medium pressure level in the refrigerant valve with expansion function (3) and absorbs heat in the ambient heat exchanger (4), subsequently expanded in the refrigerant valve with expansion function (5) and evaporated in the evaporator (6) by absorbing heat from the air and directed to the compressor (1), and a partial flow is diverted before the refrigerant valve with expansion function (3) and led via an ambient heat exchanger bypass (28) to the refrigerant valve with expansion function (10) and expanded, and subsequently evaporated in the chiller (9) and directed to the compressor (1), wherein in the battery coolant circuit (24) the coolant is pumped from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18) and the battery heat exchanger bypass (32) via the coolant auxiliary heater (21) to the Coolant pump (17) flows,the coolant auxiliary heater (21) is operated. [14] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by , that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is expanded in the refrigerant valve with expansion function (3) and absorbs heat in the ambient heat exchanger (4) and is subsequently directed via the 3 / 2-way refrigerant valve (8) and the chiller bypass (29) to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other and the coolant flows from the coolant pump (17) via the non-functional chiller (9), the 3 / 2-way coolant valve (18), the battery heat exchanger bypass (32), the coolant pump (16), the powertrain cooler (15) and the 3 / 2-way coolant valve (14) to the coolant pump (17). [15] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by , that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is expanded in the refrigerant valve with expansion function (3) and absorbs heat in the ambient heat exchanger (4) and is subsequently directed via the 3 / 2-way refrigerant valve (8) and the chiller bypass (29) to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other and the coolant flows from the coolant pump (17) via the non-functional chiller (9), the battery heat exchanger (19), the 3 / 2-way coolant valve (20), the coolant pump (16), the powertrain cooler (15) to the coolant pump (17). [16] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized bythat the refrigerant releases heat in the heating condenser (2) after the compressor (1), subsequently a partial flow is expanded in the refrigerant valve with expansion function (3) and absorbs heat in the ambient heat exchanger (4) and is subsequently directed via the 3 / 2-way refrigerant valve (8) and the chiller bypass (29) to the compressor (1), and a partial flow is diverted before the refrigerant valve with expansion function (3) and directed via an ambient heat exchanger bypass (28) to the refrigerant valve with expansion function (10) and is expanded, and is subsequently evaporated in the chiller (9) and directed to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other, and the coolant is pumped by the coolant pump (17) via the chiller (9), the 3 / 2-way refrigerant valve (18), the battery heat exchanger bypass (32), the coolant pump (16)the powertrain cooler (15) and the 3 / 2-way coolant valve (14) to the coolant pump (17). [17] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by , that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is subsequently guided via an ambient heat exchanger bypass (28) to the refrigerant valve with expansion function (10) and is expanded, is evaporated in the chiller (9) and is directed to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other and the coolant flows from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18), the battery heat exchanger bypass (32), the coolant pump (16), the powertrain cooler (15) and the 3 / 2-way coolant valve (14) to the coolant pump (17). [18] Method for operating a heat pump arrangement according to any one of claims 11 to 17, characterized by , that the air PTC (7) is operated to provide additional heating of the air for the vehicle cabin. [19] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by, that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is subsequently guided via an ambient heat exchanger bypass (28) to the refrigerant valve with expansion function (10) and is expanded, is evaporated in the chiller (9) and is directed to the compressor (1), wherein the battery coolant circuit (24) and the powertrain coolant circuit (25) are connected to each other and the coolant flows from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18), the battery heat exchanger bypass (32), the coolant pump (16), the powertrain cooler (15) and the 3 / 2-way coolant valve (14) and the coolant auxiliary heater (21) to the coolant pump (17), wherein the coolant auxiliary heater (21) is operated. [20] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by, that the refrigerant releases heat after the compressor (1) in the heating condenser (2), is subsequently guided via an ambient heat exchanger bypass (28) to the refrigerant valve with expansion function (10) and is expanded, is evaporated in the chiller (9) and is directed to the compressor (1), wherein in the battery coolant circuit (24) the coolant flows from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18) and the battery heat exchanger bypass (32) via the coolant auxiliary heater (21) to the coolant pump (17), wherein the coolant auxiliary heater (21) is operated and wherein in the powertrain coolant circuit (25) the coolant flows from the coolant pump (16) via the powertrain cooler (15), the 3 / 2-way coolant valve (22) and the powertrain loop (33) to the coolant pump (16). [21] Method for operating a heat pump arrangement according to any one of claims 1 to 6 for heating the vehicle cabin at ambient temperatures above -20 °C, characterized by , that the refrigerant releases heat after the compressor (1) in the heating condenser (2) and in the ambient heat exchanger (4), is subsequently expanded in the 3 / 2-way refrigerant valve (8) and evaporates in the chiller (9) and is directed to the compressor (1), wherein in the battery coolant circuit (24) the coolant flows from the coolant pump (17) via the chiller (9), the 3 / 2-way coolant valve (18) and the battery heat exchanger bypass (32) via the coolant auxiliary heater (21) to the coolant pump (17), wherein the coolant auxiliary heater (21) is operated and wherein in the powertrain coolant circuit (25) the coolant flows from the coolant pump (16) via the powertrain cooler (15), the 3 / 2-way coolant valve (22) and the powertrain loop (33) to the coolant pump (16).

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