Vehicle and method for air conditioning a vehicle

Abstract

Vehicle (2) which has a passenger compartment (4) and an air conditioning system (6) with a heat storage unit (10) and with an absorption air conditioning system (8) which has an evaporator (14), an absorber (16) and a cooker (18), wherein the heat storage unit (10) is designed as a latent heat storage unit, wherein a control unit (34) is arranged which is designed such that it initiates a first cooling operation in which - the passenger compartment (4) is cooled by evaporating a refrigerant in the evaporator (14), - the refrigerant in the absorber (16) is absorbed by an absorption medium and - the refrigerant in the cooker (18) is released by heating the absorption medium with heat, the heat being provided by the heat storage unit (10).

Description

[0001] The invention relates to a vehicle and a method for air conditioning a vehicle.

[0002] A vehicle's air conditioning is typically achieved through an air conditioning system. Such an air conditioning system primarily serves to dissipate heat and thus generate cold, enabling the vehicle's passenger compartment to be cooled. To generate cold, a compression air conditioning system is used, for example, with a compressor, an evaporator, an expansion valve, and a condenser. The compressor must be driven accordingly and is, for example, coupled to the vehicle's belt drive. The operation of a compressor typically leads to considerable noise.

[0003] Alternatively, the use of an adsorption system is also possible, as described, for example, in DE 10 2014 215 891 A1. Such an adsorption air conditioning system has a sorption bed in which a sorbent, e.g., zeolite, is arranged. This sorbent can be loaded with a sorbate, e.g., water, and in the process releases heat. Conversely, it is possible to evaporate the sorbate again by adding heat and dry the loaded sorbent. The required heat can be taken from the environment, thereby achieving a cooling effect. The sorption bed is necessarily loaded and unloaded cyclically, i.e., heating or cooling is not possible continuously, but only in phases.

[0004] Reference is made to DE 10 2009 030 541 A1, DE 60 2004 006 248 T2, DE 10 2005 004 397 A1, DE 42 07 857 A1, DE 36 38 706 A1, DE 199 12 139 C1, US 2011 / 0 079 023 A1 and US 2006 / 0 107 674A1.

[0005] Against this background, one object of the invention is to provide a vehicle with improved air conditioning. Furthermore, a corresponding method for air conditioning a vehicle is to be provided. Overall, a suitable air conditioning system should ensure the most consistent cooling possible and be as quiet as possible during operation.

[0006] The object is achieved according to the invention by a vehicle having the features of claim 1 and by a method having the features of claim 16. Advantageous embodiments, refinements, and variants are the subject of the dependent claims. The statements relating to the vehicle also apply mutatis mutandis to the method, and vice versa. In particular, the object is also achieved by an air conditioning system for a vehicle. Advantages and expedient embodiments emerge accordingly from the statements relating to the vehicle and the method.

[0007] The vehicle has a passenger compartment in which occupants can be accommodated. Furthermore, the vehicle has an air conditioning system with a heat accumulator and an absorption air conditioning system comprising an evaporator, an absorber, and a cooker. A control unit is also arranged, which is configured to set a first cooling mode.

[0008] In the first cooling mode, the passenger compartment is cooled by evaporating a refrigerant in the evaporator, i.e., evaporated refrigerant is generated. The evaporated refrigerant is absorbed by an absorption medium in an absorber, i.e., absorbed refrigerant is generated. In particular, the evaporated refrigerant is thereby removed from the evaporator, so that additional, liquid refrigerant flows in, and continuous cooling is achieved. Furthermore, the particularly absorbed refrigerant is released in a boiler by heating the absorption medium with thermal energy. The thermal energy is provided by the heat accumulator.

[0009] Overall, this creates a cycle for the refrigerant in which the refrigerant first absorbs heat in the evaporator and is evaporated. The refrigerant is then removed from the evaporator by the absorber to allow more refrigerant to flow in. The absorption medium is then loaded with refrigerant. The loaded absorption medium is then fed to the digester, where the refrigerant is released again by means of heat and the absorption medium is regenerated. The regenerated absorption medium is fed back to the absorber. The released refrigerant is then fed back to the evaporator. The released refrigerant is expediently cooled in a condenser and only then fed back to the evaporator. Overall, the absorption air conditioning system has two overlapping circuits: a refrigerant circuit and an absorption medium circuit.Both circuits overlap from the absorber, where the refrigerant and absorption medium are mixed, to the cooker, where the refrigerant and absorption medium are separated.

[0010] Particular advantages arise from the use of an absorption air conditioning system. This is particularly quiet in operation. The absorption air conditioning system is preferably designed without a pump and circulation takes place solely by means of the thermosiphon effect. This further reduces noise. Alternatively, a design with a circulation pump is also suitable. At the same time, continuous operation is also possible, i.e. continuous cooling or provision of cold. This results in particular from the design with two circuits described above. Since the refrigerant circulates and evaporated refrigerant is constantly removed from the evaporator and liquid refrigerant is supplied, continuous cooling is guaranteed. An absorption air conditioning system also has the advantage that it can be used even at a small temperature gradient of e.g.a few degrees Celsius, whereby the temperature gradient between the boiler and the evaporator is measured, which is advantageous when the absorption air conditioning system is started up. Continuous operation over wide temperature and temperature gradient ranges is also possible. In terms of operation, the absorption air conditioning system is also advantageously self-regulating in the sense that it automatically starts up when a corresponding temperature gradient is reached and that the cooling capacity also increases with increasing heating energy. An absorption air conditioning system can also be operated at low outside temperatures, i.e. in particular below 0°C, at which a compression air conditioning system is not operational. This means that cooling can also be achieved in winter, for example for vehicle components that require particularly high cooling requirements, such asa fuel cell, or as an alternative to cooling using ambient air if this cannot or should not be used.

[0011] A key idea of ​​the invention is in particular to use a separate heat accumulator as a particularly reliable heat source for supplying heat to and operating the absorption air conditioning system. This is based on the observation that an absorption air conditioning system must be operated with thermal heat, which in particular must be supplied continuously for continuous operation. This is not necessarily possible in the automotive sector, as permanent heat sources are usually not available here. For example, in a hybrid vehicle the combustion engine is not continuously in operation and is therefore not continuously available as a heat source. An electric car generally generates less waste heat than a vehicle powered solely by a combustion engine.But even in a vehicle powered solely by an internal combustion engine, the internal combustion engine is not necessarily in constant operation, for example, during extended stop phases or in parking mode, where air conditioning of the passenger compartment may still be desired. Therefore, a heat accumulator is used here, which advantageously serves as a heat source for operating the absorption air conditioning system regardless of the vehicle's operating state and reliably and quickly provides heat for the cooker. The heat accumulator thus represents a thermal battery, so to speak, enabling cooling regardless of the ambient conditions. The air conditioning system, as a combination of a heat accumulator and an absorption air conditioning system, is also mechanically simple, robust, and particularly quiet. A compression air conditioning system is preferably dispensed with.In addition, the heat from the heat storage can also be used profitably in summer, when heat is not usually required, by using the heat to generate cooling using the absorption system.

[0012] The absorption air conditioning system, also known as an absorption chiller, is a refrigeration system in which, unlike a compression refrigeration system, a refrigerant is absorbed at low temperature in an absorption medium, also known as a solvent, and desorbed at a comparatively higher temperature. This system exploits the temperature dependence of the physical solubility of two substances. Ammonia, for example, is used as the refrigerant, and water, suitably in a hydrogen atmosphere, is used as the absorption medium. Both substances are liquid or gaseous and can therefore be easily circulated. As described above, the absorption air conditioning system has a refrigerant circuit and enables continuous and thus advantageous on-demand cooling, unlike an adsorption system.While in such an adsorption system, a sorption bed is cyclically loaded and unloaded, thus only allowing phased cooling via the sorption bed, an absorption air conditioning system can provide continuous cooling. An adsorption system is also comparatively complex in its design and operation.

[0013] The control unit, also known as a controller, is, for example, a central control unit of the vehicle or a separate control unit of the air conditioning system. The control unit controls the absorption system and its individual components. To set the first cooling mode, the absorption system is activated, so that the refrigerant and absorption medium are circulated, and cooling is achieved via the evaporator by absorbing heat from the passenger compartment. For this purpose, the control unit also activates the heat accumulator, from which heat is then extracted.

[0014] A further advantage is that the heat accumulator also provides a reliable heat source for heating. Therefore, in an advantageous development, the air conditioning system has a cooling circuit to which at least one vehicle component is connected, for heating the vehicle component using the heat accumulator. A coolant, for example, water, circulates in the cooling circuit and serves to transport heat from the heat accumulator to the vehicle component.

[0015] In a particularly preferred embodiment, the vehicle component is a heating heat exchanger and the control unit is designed such that it sets a first heating mode in particular, in which the passenger compartment is heated by means of the heating heat exchanger. This easily realizes not only cooling but also heating of the passenger compartment. In the first cooling mode, the heat accumulator serves to drive the absorption system, whereas in heating mode the heat from the heat accumulator is used directly for heating. In an expedient further development, the first cooling mode and the heating mode are set simultaneously, thereby realizing a dehumidification mode. Air supplied to the passenger compartment is then first cooled by the evaporator and dehumidified in the process, and then reheated by the heating heat exchanger.

[0016] Advantageously, any other vehicle components can also be heated alternatively or in addition to the passenger compartment. Alternatively, the vehicle component is therefore particularly selected from a group of vehicle components comprising: a high-voltage storage unit, power electronics, an electric motor, in particular for driving the vehicle, an internal combustion engine, and an engine oil heat exchanger. These vehicle components also benefit from heating in certain, possibly different, situations. For example, in winter, when the vehicle is started, a high-voltage storage unit is heated to a certain minimum operating temperature, e.g., a temperature between 0°C and 10°C. Heating of power electronics or an electric drive motor for moving the vehicle as needed is also conceivable, e.g., 80 to 100°C. In a vehicle with an internal combustion engine, preheating engine oil using an engine oil heat exchanger is advantageous.In one variant, several vehicle components are connected to the cooling circuit, in particular the heating heat exchanger mentioned above and at least one other vehicle component.

[0017] In an advantageous embodiment, the cooker is connected to a vehicle component which generates waste heat during operation, and the control unit is designed such that it sets a second cooling mode in which the waste heat from the vehicle component is transferred to the cooker and used as heating heat. The vehicle component, or at least one of these in the case of multiple vehicle components, generates waste heat during operation, and the control unit is designed such that it sets a second cooling mode in which the waste heat is transferred to the cooker and used as heating heat. The second cooling mode is particularly advantageous in that the heat accumulator is protected and only needs to be used as a heat source when no other heat source is available. In an expedient embodiment, the first cooling mode is therefore set when the second cooling mode is not possible.In one variant, the first and second cooling modes are set simultaneously, so that the cooker is supplied with heat from both the heat storage unit and the vehicle component. This is particularly useful if the vehicle component cannot provide sufficient heat in the second cooling mode. Additional heating is then provided by the heat storage unit.

[0018] In a variant of the aforementioned embodiment, the cooker is connected to the cooling circuit described above. A number of vehicle components, in particular as heat sources, are connected to the cooling circuit. The cooling circuit thus fulfills a dual function: during heating operation, it supplies heat from the heat accumulator to the cooling circuit, and it also dissipates heat from the cooling circuit to the cooker. The underlying idea is that the cooling circuit advantageously also enables an alternative supply of heat to the cooker, i.e., supply from a heat source other than the heat accumulator.

[0019] In a suitable embodiment, the vehicle component is an engine unit, particularly preferably an internal combustion engine, or an exhaust system of the vehicle. This efficiently recovers waste heat generated during vehicle operation and uses it to operate the absorption system. The phase-change material is expediently selected such that its phase-change temperature is approximately 200°C for a gasoline-powered vehicle, approximately 130°C for a diesel-powered vehicle, and approximately 70°C for an electric vehicle. This optimally accommodates the specific temperature conditions in the aforementioned vehicle components for the respective vehicle type.

[0020] Alternatively or additionally, the vehicle component is expediently an electric motor for driving the vehicle, power electronics for controlling the electric motor, a high-voltage battery, or a fuel cell. A fuel cell is particularly suitable as a heat source, as a fuel cell generates a particularly large amount of waste heat during operation. All of these vehicle components sometimes generate considerable amounts of waste heat, which can then be advantageously used to operate the absorption system.

[0021] Various concepts for the motor unit are suitable, in particular the ones listed below. In some embodiments, the vehicle features a high-voltage battery, which fulfills different functions depending on the specific design: - Motor unit consisting of an internal combustion engine for propulsion. In this configuration, the motor unit has no electric motor or high-voltage battery. The vehicle is powered solely by an internal combustion engine. - Motor unit consisting of an internal combustion engine for propulsion. In this embodiment, the motor unit does not have an electric motor. A high-voltage storage unit is used to supply energy to consumers in the vehicle that have a high electrical energy demand, e.g., an electric charge air compressor or an electric roll stabilization system, and in particular, also require a high operating voltage, i.e., in particular, 48 to 350 V. The vehicle is then powered purely by an internal combustion engine. - Motor unit consisting of an internal combustion engine and an electric motor, each for propulsion, as well as power electronics for controlling the electric motor. A high-voltage battery supplies energy to the electric motor. The vehicle is then a hybrid vehicle. - Motor unit consisting of an electric motor for propulsion and power electronics for controlling the electric motor. A high-voltage battery supplies the electric motor with energy. The vehicle is then considered an electric vehicle. - Motor unit consisting of an electric motor for propulsion and a combustion engine as a range extender for charging a high-voltage battery, as well as power electronics for controlling the electric motor. The high-voltage battery supplies energy to the electric motor. The vehicle is then an electric vehicle with a range extender. - Motor unit consisting of an electric motor for propulsion and a fuel cell as a range extender for charging a high-voltage battery, as well as power electronics for controlling the electric motor. The high-voltage battery supplies energy to the electric motor. The vehicle is then a fuel cell vehicle, also known as an FCEV (fuel cell electric vehicle). - Motor unit consisting of an electric motor for propulsion, a fuel cell for supplying power to the electric motor, and power electronics for controlling the electric motor. A high-voltage storage unit is used to supply energy to consumers with high electrical energy requirements, for example, to bridge a fuel cell startup phase. The vehicle is then a fuel cell vehicle, also known as an FCEV (fuel cell electric vehicle).

[0022] “Consisting of” is understood in particular to mean that the motor unit only comprises those components of which the motor unit consists.

[0023] In an advantageous embodiment, the waste heat from the vehicle component is used to heat the passenger compartment in a second heating mode. This protects the heat storage unit even during heating, as waste heat from a vehicle component is expediently transferred directly to the heating heat exchanger via the cooling circuit.

[0024] If excess waste heat is generated, i.e., more waste heat than is needed for heating or to drive the absorption air conditioning system for cooling, e.g., in summer, this excess waste heat is dissipated into the environment in a suitable manner. For this purpose, a cooler is conveniently connected to the cooling circuit to dissipate the heat into the environment. The cooler is also referred to as an ambient cooler.

[0025] In a particularly preferred embodiment, the control unit is designed to set a regeneration mode in which the heat accumulator is regenerated, i.e., charged with heat. In other words, heat is not only removed from the heat accumulator, but also added back in so that this heat can be used later. The heat accumulator is thus designed to be regenerable.

[0026] In a suitable embodiment, the air conditioning system has an electric heating device for regenerating the heat accumulator, particularly in regeneration mode. The heating device generates heat, which is stored in the heat accumulator. An electric heating device is particularly efficient in this respect, since almost all of the supplied electrical energy is converted into heat. The electric heating device can be, for example, a PTC element or an electric instantaneous water heater. In a particularly practical variant, a vehicle's auxiliary heater is also used as an electric heating device. This dual function saves components, costs, and weight.

[0027] In an advantageous development, the heating device is also used in heating mode to heat the passenger compartment. For this purpose, the heating device generates heat, for example, which is transferred to the heating heat exchanger via the cooling circuit. Additionally or alternatively, the heating device directly heats the air flowing into the passenger compartment.

[0028] The vehicle is ideally equipped with a power connection for connecting the heating system to an external power grid. During regeneration mode, energy is drawn from the external power grid to regenerate the heat storage unit. The heat or the energy required for this does not need to be generated by the vehicle itself; instead, the heat storage unit is regenerated using mains power. Rather, the vehicle can be charged with heat while at rest or parked. In an electric or hybrid vehicle, the heat storage unit is conveniently regenerated during charging of the high-voltage battery. However, a corresponding charging operation for the heat storage unit is also useful in a vehicle powered solely by a combustion engine.Particularly in vehicles with so-called cold country equipment, there is often a connection for an auxiliary heater or engine auxiliary heater, which is then conveniently used to operate the heating device and thus to regenerate the heat storage unit.

[0029] Alternatively or additionally, the heat storage device is expediently regenerated by operating the electric heating device with electricity from a generator or the vehicle's electrical energy storage device. In contrast to the regeneration using mains power described above, this regeneration takes place using on-board power. The electrical energy storage device is, for example, a battery; in an electric or hybrid vehicle, for example, a high-voltage storage device, which also serves to store energy for the vehicle's propulsion.

[0030] Alternatively or additionally, the heat storage unit is suitably regenerated by transporting waste heat from a vehicle component to the heat storage unit via the cooling circuit.

[0031] Advantageously, the control unit is designed such that it sets a recuperation mode in which energy is recuperated, by means of which the heat accumulator is regenerated. “Recuperated energy” is understood to mean energy that is recovered while the vehicle is in operation. This is particularly the case during braking. During braking, energy must be destroyed in order to slow the vehicle down. This energy is expediently recuperated and used for other purposes, in this case preferably for regenerating the heat accumulator. In a first embodiment, the energy is converted directly into heat by a braking device, which is then suitably fed to the heat accumulator. For example, the heat is absorbed via a brake heat exchanger in the vehicle's brakes and passed on to the heat accumulator. For this purpose, the brake heat exchanger is connected, for example, to the cooling circuit.Alternatively or additionally, the energy is recovered by converting it into electrical energy using a generator, which in turn is converted into heat, e.g., by an electric heater. This heat is then stored in the heat storage unit.

[0032] The air conditioning system preferably has a hot circuit for transferring heat from the heat accumulator to the cooker and, in the variant with a cooling circuit, expediently also to the cooling circuit. This advantageously thermally decouples the heat accumulator from the cooker. In a configuration with a cooling circuit, the heat accumulator is then advantageously also thermally decoupled from the other vehicle components. Heat exchange between the hot circuit and the cooling circuit then expediently takes place via a suitable heat exchanger, which thermally connects the hot circuit to the cooling circuit. In particular, a thermal oil, i.e. a heat transfer oil, circulates in the hot circuit as a heat medium. By using a hot circuit, the heat from the heat accumulator can be distributed more efficiently and easily.In a suitable embodiment, the hot circuit can be switched by means of suitable valves and the heat is distributed to the cooker and the cooling circuit, in particular as required, depending on whether cooling or heating mode or both is set.

[0033] In this case, the heat storage device is designed as a latent heat storage device. Alternatively or additionally, a design as a sensible or thermochemical heat storage device is also suitable. However, a latent heat storage device is particularly advantageous because it can store particularly large amounts of heat and releases this heat, above all, at a constant temperature. This makes operation significantly easier than other heat storage device designs. The latent heat storage device consists in particular of a phase change material. Such a material is characterized in particular by the fact that its latent heat of fusion, heat of solution, or heat of absorption is significantly greater than the heat that the phase change material could absorb due to its specific heat capacity. A significant amount of heat is therefore absorbed and released during a phase transition and thus advantageously at a constant temperature, namely the phase change temperature.This depends particularly on the material.

[0034] In principle, a burner, gas burner, or similar device is also suitable for providing heat for the cooker. However, the heat storage devices described above have the advantage that the heat storage device itself is not consumed, but rather only the energy stored therein. For regeneration, the heat storage device does not need to be refilled; rather, it is simply charged with new heat, which is generated particularly easily, in particular, by the heating device described above. Furthermore, compared to a fuel-powered burner, the heat storage device, in particular the latent heat storage device, can be advantageously regenerated using waste heat from other vehicle components and, above all, also using recovered energy.

[0035] A particularly suitable embodiment is one in which the heat storage device has a high-temperature storage medium which releases heat at a temperature of at least 200°C and at most 500°C, preferably at most 300°C. In general, the heat storage device has a storage medium for storing the heat. The storage medium is preferably a salt. The capacity of the storage medium is, for example, approximately 3 to 5kWh, but this can also vary. The storage medium has the highest possible energy density in order to store as much heat as possible in the smallest possible space. A high-temperature storage medium is particularly suitable for this purpose, i.e. a storage medium which, when releasing heat, has a temperature, in particular a phase change temperature, in the range between 200 and 500°C. In this range, the phase transition occurs with the release of heat, particularly in the case of a latent heat storage device.From a design perspective, an upper limit of 500°C is particularly suitable for this range. A temperature of approximately 270°C is preferred for heat dissipation. At these temperatures, a particularly rapid provision of heat for cooling and / or heating is ensured.

[0036] For regeneration, the heat storage device is heated, in particular. In the case of a high-temperature storage medium, preferably also at a temperature of at least 200°C and at most 500°C, in particular at most 300°C. The heat storage device is expediently electrically charged in the embodiment with a high-temperature storage medium, since the corresponding temperatures are particularly easy to achieve in this way, for example, using the electric heating device described above.

[0037] The concept is generally suitable for all vehicle types, but particularly useful for those that can be connected to a power grid. Therefore, the vehicle is preferably an electric or hybrid vehicle. A vehicle with cold-weather equipment, i.e., with a power connection for, for example, an engine heater, is also particularly suitable.

[0038] The method is used for air conditioning a vehicle having a passenger compartment and an air conditioning system with a heat accumulator and an absorption air conditioning system comprising an evaporator, an absorber, and a cooker. A first cooling mode is set in which the passenger compartment is cooled by evaporating a refrigerant in the evaporator, absorbing the refrigerant in an absorber by an absorption medium, and releasing the refrigerant in a cooker by heating the absorption medium with thermal energy, the thermal energy being provided by the heat accumulator. Appropriate embodiments and advantages will emerge analogously from the above explanations.

[0039] Generally, for cooling multiple vehicle components in addition to the passenger compartment, the absorption air conditioning system is expediently designed with multiple evaporators or a multi-part evaporator to fulfill various air conditioning tasks. Various air conditioning tasks are particularly those that are conventionally served via a low-temperature cooling circuit, e.g., cooling of electronic components or vehicle seats. The design with multiple evaporators or a multi-part evaporator is expediently combined with a design with multiple cookers or a multi-part cooker. This ensures particularly flexible air conditioning overall.

[0040] An exemplary embodiment of the invention is explained in more detail below with reference to a drawing. The drawings schematically show: Fig. 1 a vehicle and Fig. 2 an air conditioning system.

[0041] Fig. Figure 1 shows a vehicle 2 with a passenger compartment 4, which is air-conditioned by an air conditioning system 6. For this purpose, the system comprises an absorption air conditioning system 8 and a heat accumulator 10 for supplying the absorption air conditioning system 8 with heat. The vehicle 2 further comprises an engine 12, i.e., a motor unit, which is an electric motor here, for driving the vehicle 2.

[0042] The functioning of the air conditioning system 6 is explained below using Fig. 2. This shows a highly schematic representation of the air conditioning system 6 and its individual components, as well as their interaction with other parts of the vehicle 2.

[0043] First, the absorption air conditioning system 8 is shown in more detail. It has an evaporator 14 in which a refrigerant is evaporated. In the process, heat is extracted from the surroundings of the evaporator 14 and cooling is achieved. This is used to extract heat from the passenger compartment 4 and cool it. The evaporated refrigerant is absorbed by an absorption medium in an absorber 16. As a result, the evaporated refrigerant is extracted from the evaporator 14, so that further, liquid refrigerant flows in and continuous cooling is achieved. Furthermore, the absorbed refrigerant is released again in a boiler 18 by heating the absorption medium with thermal energy. The thermal energy is provided by the heat accumulator 10. In addition, Fig. 2, the released refrigerant is cooled in a condenser 20 and only then fed back to the evaporator 14. Overall, the absorption air conditioning system 8 thus has two overlapping circuits 22, 24, namely a refrigerant circuit 22 and an absorption medium circuit 24. Both circuits 22, 24 overlap from the absorber 16, in which the refrigerant and absorption medium are mixed, to the cooker 18, in which the refrigerant and absorption medium are separated from each other.

[0044] The heat is transferred from the heat accumulator 10 to the cooker 18 via a hot circuit 26, to which the two components are connected and in which a thermal oil, generally a heat transfer medium, circulates. The hot circuit 26 is further connected to a cooling circuit 28, in which Fig. 2 via a heat exchanger 30. A heat transfer medium, e.g. water, circulates in the cooling circuit 28 and can then be heated with heat from the heat accumulator 10. To heat the passenger compartment 4, a heating heat exchanger 32 is connected to the cooling circuit and releases heat to the passenger compartment 4. Thus, the heat from the heat accumulator is used, on the one hand, in a first cooling mode by means of the absorption air conditioning system 8 to cool the passenger compartment 4, and, on the other hand, in a heating mode by means of the heating heat exchanger 32 to heat the passenger compartment 4. This dual function of the heat accumulator 10 leads to particularly efficient use of the same. The heat accumulator 10 is used to air condition the vehicle both in summer and in winter.

[0045] The heat accumulator 10 also represents a particularly reliable heat source, which is also available regardless of the operating state of the vehicle 2. Thus, a cooling or heating mode can be set at any time, in which the passenger compartment 4 is air-conditioned accordingly. The setting is made by means of a control unit 34, which is, for example, a central control unit of the vehicle 2.

[0046] In the illustrated embodiment, the heat accumulator 10 is a latent heat accumulator consisting of a phase-change material, which in this case is also a high-temperature storage medium. The phase-change material is, in particular, a salt with a phase-change temperature in the range of 200 to 500°C. The phase-change temperature is preferably approximately 270°C. To regenerate the heat accumulator 10, the vehicle 2 has an electric heating device 36, by means of which the phase-change material is heated and charged with heat. The heating device 36 is, in turn, supplied with energy via a power connection 38. Via this power connection 38, the vehicle 2 is connected to an external power grid 40, from which energy is then drawn to charge the heat accumulator. In the illustrated embodiment, the power connection 38 also serves to charge a high-voltage storage device 42 of the vehicle 2 using a power supply 44.

[0047] Alternatively or additionally, a recuperation mode is set, in which energy is recuperated, by means of which the heat accumulator 10 is then regenerated. The recuperated energy is recovered during driving of the vehicle 2, e.g., during braking. For example, heat is generated by a braking device (not shown), which is then supplied to the heat accumulator 10. Alternatively or additionally, the energy is recuperated and converted into electrical energy by means of a generator (not shown), by means of which the electrical heating device 36 is operated.

[0048] As from Fig.2, in addition to the heating heat exchanger 32, further vehicle components are connected to the cooling circuit 28, in this case the high-voltage storage unit 42, the engine 12, power electronics 46 and a cooler 48. In a variant not shown, the power supply unit 44 is also connected to the cooling circuit 28. The power electronics 46 serve to supply the engine 12 with energy from the high-voltage storage unit 42. The cooler 48 serves to dissipate heat to the environment, i.e. to cool the engine 12. By being connected to the cooling circuit 28, the aforementioned vehicle components can also be heated with heat from the heat storage unit 10. This is particularly useful, for example, in winter to preheat the high-voltage storage unit 42, the power electronics 46 and / or the engine 12 to a certain operating temperature. In an embodiment not shown, in which the engine 12 is an internal combustion engine, an engine heater can be implemented in this way.For example, the engine 12 is preheated by means of an engine oil heater, in which the engine oil is heated via an engine oil heat exchanger.

[0049] In the illustrated embodiment, the cooker 18 is also connected to the cooling circuit 28. This allows waste heat from the aforementioned vehicle components to be used as heating heat to operate the absorption air conditioning system 8 in a second cooling mode. For example, waste heat from the engine 12 is transferred to the cooker 18 instead of being released into the environment via the cooler 48. Waste heat from the high-voltage storage unit 42 and the power electronics 46 can also be used accordingly and is not lost. This makes the air conditioning system 6 particularly efficient. List of reference symbols 2 vehicles 4 Passenger compartment 6 Air conditioning system 8 Absorption air conditioning system 10 heat storage units 12 Engine 14 evaporators 16 absorbers 18 cookers 20 Capacitor 22 Refrigerant circuit 24 Absorption medium circuit 26 Hot circuit 28 Cooling circuit 30 heat exchangers 32 heating heat exchangers 34 Control unit 36 Heating device 38 Power connection 40 external power grid 42 high-voltage storage units 44 Power supply 46 Power electronics 48 coolers

Claims

[1] Vehicle (2) having a passenger compartment (4) and an air conditioning system (6), with a heat accumulator (10) and with an absorption air conditioning system (8) having an evaporator (14), an absorber (16) and a cooker (18), wherein the heat accumulator (10) is designed as a latent heat accumulator, wherein a control unit (34) is arranged, which is designed such that it sets a first cooling mode in which - the passenger compartment (4) is cooled by evaporating a refrigerant in the evaporator (14), - the refrigerant is absorbed in the absorber (16) by an absorption medium and - the refrigerant is released in the cooker (18) by heating the absorption medium with heat, the heat being provided by the heat accumulator (10). [2] Vehicle (2) according to the preceding claim, characterized bythat the air conditioning system (6) has a cooling circuit (28) to which at least one vehicle component (12, 32, 42, 46) is connected, for heating the at least one vehicle component (12, 32, 42, 46) by means of the heat accumulator (10). [3] Vehicle (2) according to the preceding claim, characterized by that the at least one vehicle component (12, 32, 42, 46) is a heating heat exchanger (32) and that the control unit (34) is designed such that it sets a heating operation in which the passenger compartment (4) is heated by means of the heating heat exchanger (32). [4] Vehicle (2) according to one of the two preceding claims, characterized by that the at least one vehicle component (12, 32, 42, 46) is selected from a group of vehicle components (12, 32, 42, 46) comprising: a high-voltage storage device (42), power electronics (46), an electric motor, an internal combustion engine, and an engine oil heat exchanger. [5] Vehicle (2) according to one of the preceding claims, characterized by that the cooker (18) is connected to a vehicle component (12, 42, 46) which generates waste heat during operation, and that the control unit (34) is designed such that it sets a second cooling operation in which the waste heat of the vehicle component (12, 42, 46) is transferred to the cooker (18) and is used as heating heat. [6] Vehicle (2) according to one of the preceding claims, characterized by that a vehicle component (12, 42, 46) is an internal combustion engine, an exhaust system, an electric motor for driving, power electronics (46) for controlling the electric motor, a high-voltage storage device (42) or a fuel cell. [7] Vehicle (2) according to one of claims 2 to 6, characterized by that a cooler (48) is connected to the cooling circuit (28) for heat dissipation to the environment. [8] Vehicle (2) according to one of the preceding claims, characterized bythat the control unit (34) is designed such that it sets a regeneration mode in which the heat accumulator (10) is regenerated. [9] Vehicle (2) according to one of the preceding claims, characterized by that it has an electric heating device (36) for regenerating the heat accumulator (10). [10] Vehicle (2) according to the preceding claim, characterized by that it has a power connection (38) for connecting the heating device (36) to an external power supply (40). [11] Vehicle (2) according to one of the preceding claims, characterized by that the control unit (34) is designed such that it sets a recuperation mode in which energy is recuperated, by means of which the heat accumulator (10) is regenerated. [12] Vehicle (2) according to one of the preceding claims, characterized bythat the air conditioning system (6) has a hot circuit (26) for transferring heat from the heat accumulator (10) to the cooker (18). [13] Vehicle (2) according to one of the preceding claims, characterized by that the heat accumulator (10) has a high-temperature storage medium which releases heat at a temperature of at least 200°C and at most 500°C, preferably at most 300°C. [14] Vehicle (2) according to one of the preceding claims, characterized by that this is an electric or hybrid vehicle. [15] Vehicle (2) according to one of the preceding claims, characterized by that the absorption air conditioning system (8) is designed with several evaporators (14) or a multi-part evaporator (14) in order in particular to fulfil various air conditioning tasks. [16] Method for air conditioning a vehicle (2) having a passenger compartment (4) and an air conditioning system (6) with a heat accumulator (10) and with an absorption air conditioning system (8) having an evaporator (14), an absorber (16) and a cooker (18), wherein the heat accumulator (10) is designed as a latent heat accumulator, wherein a first cooling operation is set in which - the passenger compartment (4) is cooled by evaporating a refrigerant in the evaporator (14), - the refrigerant is absorbed by an absorption medium in an absorber (16) and - the refrigerant is released in a cooker (18) by heating the absorption medium with thermal heat, the thermal heat being provided by the heat accumulator (10).

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