Climate cycle for a hybrid vehicle, hybrid vehicle and method for preheating a vehicle battery of a hybrid vehicle

Abstract

Climate circuit (10) for a hybrid motor vehicle, with an intercooler (12) for cooling charge air for a turbocharger of an internal combustion engine using a cooling medium, a low-temperature cooler (14) for cooling the cooling medium of the charge air cooler (12), a climate condenser (18) for dehumidifying air for air conditioning of a vehicle interior of the hybrid motor vehicle using a coolant, wherein the air conditioning condenser (18) can be connected to the low-temperature cooler (14) for cooling the coolant of the air conditioning condenser (18), and a temperature control line (22) for direct or indirect temperature control of a motor vehicle battery (24), in particular a traction battery for the purely electric drive of the hybrid motor vehicle, wherein the climate condenser (18) can be connected to the temperature control line (22) for heating the motor vehicle battery (24).

Description

[0001] The invention relates to an air conditioning circuit for a hybrid motor vehicle, a hybrid motor vehicle, an air conditioning circuit for a hybrid motor vehicle, a hybrid motor vehicle and a method for preheating a motor vehicle battery of a hybrid motor vehicle, with the aid of which a motor vehicle battery, in particular a traction battery of a hybrid motor vehicle, can be tempered in order to set a suitable operating temperature for the motor vehicle battery.

[0002] From WO 2011 / 085760 A1 it is known to use a refrigeration machine in an air conditioning system of a motor vehicle to cool air in order to dehumidify it. The dehumidified air can then be heated and fed from the air conditioning system into the interior of the motor vehicle at a desired temperature. The heat generated in a condenser in a refrigeration circuit of the refrigeration machine can be absorbed by a further circuit via a first heat exchanger and used to control the temperature of a motor vehicle battery. The further circuit additionally has a heater connected in parallel to the first heat exchanger and a second heat exchanger connected in parallel, with the aid of which the dehumidified air is heated. The volume flows of a coolant through the first heat exchanger, through the heater and the second heat exchanger can be suitably divided in order to be able to set a specific temperature for controlling the temperature of the motor vehicle battery.

[0003] From DE 11 2013 000 832 T5 an air conditioning circuit for cooling a motor vehicle battery is known, in which various motor vehicle units to be cooled and an external heat exchanger can be provided.

[0004] There is a constant need to be able to temperature control a motor vehicle battery, especially a traction battery, of a hybrid vehicle in an energy-efficient manner.

[0005] It is the object of the invention to show measures that enable energy-efficient temperature control of a motor vehicle battery, in particular a traction battery, of a hybrid motor vehicle.

[0006] The object is achieved according to the invention by an air conditioning circuit having the features of claim 1, a hybrid motor vehicle having the features of claim 8 and a method having the features of claim 9. Preferred embodiments of the invention are specified in the subclaims and the following description, which may each individually or in combination represent an aspect of the invention.

[0007] According to the invention, an air conditioning circuit for a hybrid motor vehicle is provided, comprising an intercooler for cooling charge air for a turbocharger of an internal combustion engine with the aid of a cooling medium, a low-temperature cooler for cooling the cooling medium of the intercooler, an air conditioning condenser for dehumidifying air conditioning air for air conditioning a vehicle interior of the hybrid motor vehicle with the aid of a cooling liquid, wherein the air conditioning condenser can be connected to the low-temperature cooler for cooling the cooling liquid of the air conditioning condenser, and a temperature control line for directly or indirectly controlling the temperature of a motor vehicle battery, in particular a traction battery for the purely electric drive of the hybrid motor vehicle, wherein the air conditioning condenser can be connected to the temperature control line for heating the motor vehicle battery.

[0008] The low-temperature cooler can be designed, for example, as an air-cooled cooler, in particular as a front-mounted motor vehicle cooler, which can use airflow to cool the cooling medium for the charge air cooler and / or the coolant for the air conditioning condenser. This utilizes the knowledge that the charge air cooler requires high cooling capacity in the low-temperature cooler at high driving speeds of the hybrid vehicle, while the air conditioning condenser requires high cooling capacity in the low-temperature cooler at low driving speeds of the hybrid vehicle, when the air to be dehumidified has a correspondingly higher temperature that must be cooled by the air conditioning condenser due to the lower cooling effects of the airflow.This eliminates the need to design the low-temperature cooler for the combined maximum cooling capacity required by the air conditioning condenser and the charge air cooler, allowing sufficient cooling to be achieved with a smaller air inlet area for the low-temperature cooler. This saves installation space and enables particularly energy-efficient operation by avoiding oversizing the low-temperature cooler.

[0009] At the same time, it is possible to divert the coolant into the temperature control line to use the heated coolant from the air conditioning condenser to heat the vehicle battery, thereby cooling the coolant from the vehicle battery. This allows the coolant from the air conditioning condenser to be used directly without first requiring heat transfer between two cooling fluids in separate circuits using an intermediate heat exchanger. This reduces the required cooling capacity of the low-temperature cooler, while also reducing the required heating capacity for heating the vehicle battery.Particularly when the hybrid vehicle is idling, the electrical power consumption of the vehicle battery, especially when designed as a traction battery, can be comparatively low, so that the vehicle battery can cool down and fall below its optimal operating temperature. Since the maximum power of the air conditioning condenser can be required precisely when the hybrid vehicle is idling, the coolant leaving the air conditioning condenser is particularly warm, so that the heat of the coolant can be used effectively to heat the vehicle battery in an energy-efficient manner.By cooling both the cooling medium of the charge air cooler and the cooling liquid of the air conditioning condenser in the low-temperature cooler and by utilizing the heat of the heated cooling liquid leaving the air conditioning condenser to heat the motor vehicle battery, the heat absorbed by the cooling liquid can be further utilized and the required cooling capacity of the low-temperature cooler can be reduced, so that energy-efficient temperature control of the motor vehicle battery, in particular the traction battery, of the hybrid vehicle is possible.

[0010] The air conditioning condenser is, in particular, a water-based condenser in which the cooling fluid, in particular cooling water, cooling oil, or a refrigerant, flows through the condenser without a phase change. The air conditioning condenser can, in particular, have a collector in which the air humidity condensed from the cooled air conditioning can be collected and, in particular, discharged. The air conditioning air can thereby be dehumidified. The air conditioning air can then be heated to a desired temperature, wherein a desired humidity of the air conditioning air can be set with the aid of the air conditioning condenser. The charge air cooler can, in particular, cool the charge air indirectly with the aid of the cooling medium, in particular cooling water, cooling oil, or a refrigerant.The charge air may have previously been compressed by a turbocharger and cooled by the charge air cooler before the charged and cooled charge air is fed to an internal combustion engine, in particular a combustion engine. The temperature control line may, in particular, be part of a separate circuit in which a temperature control fluid can be heated and / or cooled to a desired temperature in order to set and / or regulate a desired temperature of the motor vehicle battery. The temperature control fluid is, in particular, selected to be identical to the coolant of the air conditioning condenser, so that the coolant of the air conditioning condenser can flow through the temperature control line without problems, and mixing of the coolant and the temperature control fluid is not a problem.Preferably, the temperature control fluid can flow through the vehicle battery, achieving direct temperature control of the vehicle battery without an intermediate heat transfer medium. By avoiding heat transfer between different heat transfer media, energy efficiency can be further improved.

[0011] In particular, the low-temperature cooler, the air conditioning condenser, and the temperature control line can be connected to form a preheating circuit through which the coolant of the air conditioning condenser flows. The coolant of the air conditioning condenser can then flow from the air conditioning condenser through the temperature control line and then through the low-temperature cooler and be returned to the air conditioning condenser. The vehicle battery, which is tempered by the temperature control line, can act as an additional cooler for the coolant of the air conditioning condenser.In particular in a "ReHeat" operation, when, in particular during electric travel of the hybrid vehicle, power, in particular electrical power of the vehicle battery, is used to operate the air conditioning condenser to dehumidify the air conditioning air and subsequently power, in particular electrical power of the vehicle battery, is used to heat the air conditioning air, the heat of the coolant leaving the air conditioning condenser can be used sensibly and energy-efficiently for the temperature control of the vehicle battery and / or heating of the air conditioning air.

[0012] The temperature control line preferably has a heater for heating a temperature control fluid provided in the temperature control line, wherein, in particular, a heating power provided by the heater can be diverted at least partially to heat the air conditioning air dehumidified by the air conditioning condenser. The heater can be used to heat the temperature control fluid in the temperature control line to a suitable temperature. This is particularly helpful if the cooling fluid coming from the air conditioning condenser and fed to the temperature control line is not warm enough or if the cooling fluid of the air conditioning condenser and the temperature control fluid of the temperature control line flow in separate circuits. Preferably, a power of the heater can be used to heat the air conditioning air, in particular after the air conditioning air has been dehumidified with the aid of the air conditioning condenser.For this purpose, for example, the air conditioning air can flow along a heated heat transfer surface of the heater protruding from the temperature control line.

[0013] Particularly preferably, a high-temperature circuit is provided for cooling the internal combustion engine, wherein the high-temperature circuit can be connected to the temperature control line to form a common heating circuit for heating the motor vehicle battery with the aid of a cooling fluid of the high-temperature circuit. Particularly during mechanical operation of the hybrid vehicle, when the drive power for propulsion of the hybrid vehicle is generated by the internal combustion engine and not by the motor vehicle battery, the internal combustion engine can heat up while the motor vehicle battery can cool down. The heat dissipated by the internal combustion engine can then be used to control the temperature of the motor vehicle battery, so that an optimal operating temperature can be regulated for both the internal combustion engine and the motor vehicle battery in an energy-efficient manner.In particular, a heat transfer medium of the high-temperature circuit is selected to be identical to the tempering fluid of the tempering line, so that the heat transfer medium of the high-temperature circuit can flow through the tempering line without problems and it does not pose a problem if the heat transfer medium and the tempering fluid mix.

[0014] In particular, a bypass line connectable to the air conditioning condenser and the temperature control line is provided. The bypass line directs the air conditioning condenser's coolant past the low-temperature cooler and can be connected to the air conditioning condenser and the temperature control line to form a common delta-operated circuit. In particular, if the air conditioning condenser's coolant can be cooled sufficiently by the vehicle battery in the temperature control line, it is not necessary to have the coolant additionally cooled by the low-temperature cooler. Instead, the cooling capacity of the low-temperature cooler can be used to cool the cooling medium of the charge air cooler.

[0015] Preferably, the air conditioning condenser is connected to the low-temperature cooler and the temperature control line via a condenser valve, in particular designed as a 3 / 2-way valve. In a first switching position of the condenser valve, the air conditioning condenser is connected to the low-temperature cooler and, in a second switching position of the condenser valve, the air conditioning condenser is connected to the temperature control line. In particular, the temperature control line is connected to the low-temperature cooler via a return check valve. With the aid of the condenser valve, the mass flow of the cooling liquid can easily be directed entirely or partially via the temperature control line or past the temperature control line. The return check valve can prevent the cooling liquid, which is actually directed past the temperature control line, from inadvertently entering the temperature control line in the opposite flow direction.

[0016] Particularly preferably, the temperature control line has an inlet line connectable to the air conditioning condenser and an outlet line connectable to the low-temperature cooler, wherein the inlet line and the outlet line are connectable to one another via a connecting line having a shut-off valve. With the aid of the connecting line, a separate temperature control circuit can be formed, in which the temperature control liquid can be circulated, in particular with the aid of a temperature control compressor preferably designed as a pump. The shut-off valve can interrupt the fluid connection between the inlet line and the outlet line, in particular if the air conditioning condenser is connected to the inlet line of the temperature control line, so that the cooling liquid conveyed through the temperature control line can be conveyed back to the air conditioning condenser rather than in the temperature control circuit.Particularly preferably, a high-temperature circuit for cooling the internal combustion engine can be connected to the temperature control circuit via the shut-off valve.

[0017] The invention further relates to a hybrid motor vehicle having an internal combustion engine for purely mechanical drive of the hybrid motor vehicle, a traction battery for purely electric drive of the hybrid motor vehicle, and an air conditioning circuit, which can be designed and developed as described above, for controlling the temperature of the traction battery. By cooling both the cooling medium of the charge air cooler and the cooling fluid of the air conditioning condenser in the low-temperature cooler of the air conditioning circuit and by utilizing the heat of the heated cooling fluid leaving the air conditioning condenser to heat the motor vehicle battery, the heat absorbed by the cooling fluid can be further utilized and the required cooling capacity of the low-temperature cooler can be reduced, thus enabling energy-efficient temperature control of the motor vehicle battery, in particular the traction battery, of the hybrid motor vehicle.

[0018] The invention further relates to a method for preheating a motor vehicle battery, in particular a traction battery, of a hybrid motor vehicle, with the aid of an air conditioning circuit which can be designed and developed as described above, in which, below a limit temperature of the motor vehicle battery, the cooling liquid heated by the air conditioning condenser is used to heat the motor vehicle battery.By cooling both the cooling medium of the charge air cooler and the cooling liquid of the air conditioning condenser in the low-temperature cooler of the air conditioning circuit and by utilizing the heat of the heated cooling liquid leaving the air conditioning condenser to heat the motor vehicle battery, the heat absorbed by the cooling liquid can be further utilized and the required cooling capacity of the low-temperature cooler can be reduced, so that energy-efficient temperature control of the motor vehicle battery, in particular the traction battery, of the hybrid vehicle is possible.

[0019] In particular, the coolant heated by the air conditioning condenser is used to heat the vehicle battery when the driving speed of the hybrid vehicle is below a certain limit. At a correspondingly low driving speed, the air conditioning condenser is expected to be highly efficient, so the cooling water in the air conditioning condenser has a sufficiently high temperature to heat the vehicle battery, which has cooled below the limit temperature.

[0020] The invention will be explained below by way of example with reference to the accompanying drawings using preferred embodiments, wherein the features presented below can represent an aspect of the invention both individually and in combination. They show: Fig. 1: a schematic representation of a climate cycle, Fig. 2: a schematic representation of the air conditioning circuit in a first circuit, Fig. 3: a schematic representation of the air conditioning circuit in a second circuit, Fig. 4: a schematic representation of the air conditioning circuit in a third circuit and Fig. 5: a schematic representation of the air conditioning circuit in a fourth circuit.

[0021] The Fig. The air conditioning circuit 10 shown in Figure 1 has an indirect charge air cooler 12 cooled by a cooling medium, which is connected to a low-temperature cooler 14 for cooling the cooling medium. The cooling medium can be conveyed by means of a compressor 16. Additionally, a water-based air conditioning condenser 18 is provided for dehumidifying the air conditioning air, which has a collector 20 for removing the condensed moisture from the air conditioning air. A cooling fluid from the air conditioning condenser 18 can be conveyed in the circuit by means of an air conditioning compressor 21, which is designed, in particular, as a pump.

[0022] When dehumidifying the air conditioning air, the cooling liquid is heated in the air conditioning condenser 18, which, as in Fig. 2, can also be cooled in the low-temperature cooler 14. In addition, a temperature control line 22 is provided for temperature control of a motor vehicle battery 24 designed as a traction battery for the purely electric drive of a hybrid motor vehicle, wherein the temperature control line 22 can have a heater 26 for heating a temperature control fluid of the temperature control line 22 and / or a cooler for cooling the temperature control fluid in order to set a suitable temperature for temperature control of the motor vehicle battery 24. The temperature control line 22 can have an inlet line 28 leading to the motor vehicle battery 24 and an outlet line 30 coming from the motor vehicle battery 24, which can be connected to a common circuit via a connecting line 32. The temperature control fluid can be pumped in a circuit with the aid of a temperature control compressor 34.

[0023] As in Fig. As shown in Figure 3, a high-temperature circuit 36, which is provided for cooling an internal combustion engine of the hybrid motor vehicle, can be connected to the temperature control line 22, whereby the temperature control line 22 and the high-temperature circuit 36 ​​form a common heating circuit 38. For this purpose, a cooling fluid from the high-temperature circuit 36 ​​can be fed via a shut-off valve 40 provided in the connecting line 32 and fed back to the high-temperature circuit via the outlet line 30.

[0024] As in Fig. As shown in Figure 4, the air conditioning condenser 18 can be selectively connected to the inlet line 28 of the temperature control line 22 via a condenser valve 42, while the outlet line 30 can return the coolant from the air conditioning condenser 18 to the low-temperature cooler 14 and the air conditioning condenser 18 via a return check valve 44. The low-temperature cooler 14, the air conditioning condenser 18, and the temperature control line 22 can form a common preheating circuit 46. A short-circuit flow via the connecting line 32 past the motor vehicle battery 24 can be prevented by the shut-off valve 40 and / or a connecting check valve 47 provided in the connecting line 32.

[0025] As in Fig. 5 can be compared to the one shown in Fig.4, the cooling fluid coming from the temperature control line 22 is routed past the low-temperature cooler 14 via a bypass line 48 with the aid of a bypass valve. An air conditioning check valve 50 provided between the low-temperature cooler 14 and the bypass line 48 can prevent the cooling fluid from flowing in the opposite direction through the low-temperature cooler 14. The air conditioning condenser 18 and the temperature control line 22 can thus form a common delta-operated circuit without the low-temperature cooler 14.

Claims

[1] Air conditioning circuit (10) for a hybrid vehicle, with a charge air cooler (12) for cooling charge air for a turbocharger of an internal combustion engine with the aid of a cooling medium, a low-temperature cooler (14) for cooling the cooling medium of the charge air cooler (12), an air conditioning condenser (18) for dehumidifying air conditioning for air conditioning a vehicle interior of the hybrid motor vehicle with the aid of a cooling liquid, wherein the air conditioning condenser (18) is connectable to the low-temperature cooler (14) for cooling the cooling liquid of the air conditioning condenser (18), and a temperature control line (22) for the direct or indirect temperature control of a motor vehicle battery (24), in particular a traction battery for the purely electric drive of the hybrid motor vehicle, wherein the air conditioning condenser (18) can be connected to the temperature control line (22) for heating the motor vehicle battery (24). [2] Air conditioning circuit (10) according to claim 1 characterized by that the low-temperature cooler (14), the air conditioning condenser (18) and the tempering line (22) can be connected to form a preheating circuit (46) through which the cooling liquid of the air conditioning condenser (18) can flow. [3] Air conditioning circuit (10) according to claim 1 or 2 characterized by in that the temperature control line (22) has a heater (26) for heating a temperature control liquid provided in the temperature control line (22), wherein in particular a heating power that can be provided by the heater (26) can be branched off at least partially for heating the air conditioning air dehumidified by the air conditioning condenser (18). [4] Air conditioning circuit (10) according to one of claims 1 to 3 characterized bythat a high-temperature circuit (36) is provided for cooling the internal combustion engine, wherein the high-temperature circuit (36) can be connected to the tempering line (22) to form a common heating circuit (38) for heating the motor vehicle battery (24) with the aid of a cooling fluid of the high-temperature circuit (36). [5] Air conditioning circuit (10) according to one of claims 1 to 4 characterized by that a bypass line (48) connectable to the air conditioning condenser (18) and the temperature control line (22) is provided, wherein the bypass line (48) guides the cooling liquid of the air conditioning condenser (18) past the low-temperature cooler (14) and can be connected together with the air conditioning condenser (18) and the temperature control line (22) to form a common delta operation circuit. [6] Air conditioning circuit (10) according to one of claims 1 to 5 characterized byin that the air conditioning condenser (18) is connected to the low-temperature cooler (14) and the temperature control line (22) via a condenser valve (42), in particular designed as a 3 / 2-way valve, wherein in a first switching position of the condenser valve (42) the air conditioning condenser (18) is connected to the low-temperature cooler (14) and in a second switching position of the condenser valve (42) the air conditioning condenser (18) is connected to the temperature control line (22), wherein in particular the temperature control line (22) is connected to the low-temperature cooler (14) via a return check valve (44). [7] Air conditioning circuit (10) according to one of claims 1 to 6 characterized byin that the temperature control line (22) has an inlet line (28) which can be connected to the air conditioning condenser (18) and an outlet line (30) which can be connected to the low-temperature cooler (14), wherein the inlet line (28) and the outlet line (30) can be connected to one another via a connecting line (32) which has a shut-off valve (40). [8] Hybrid motor vehicle with an internal combustion engine for purely mechanical drive of the hybrid motor vehicle, a traction battery for purely electrical drive of the hybrid motor vehicle and an air conditioning circuit (10) according to one of claims 1 to 7 for tempering the traction battery. [9] Method for preheating a motor vehicle battery (24), in particular a traction battery, of a hybrid motor vehicle, with the aid of an air conditioning circuit (10) according to one of claims 1 to 7, in which below a limit temperature of the motor vehicle battery (24) the cooling liquid heated by the air conditioning condenser (18) is used to heat the motor vehicle battery (24). [10] Method according to claim 9, wherein the cooling liquid heated by the air conditioning condenser (18) is used to heat the motor vehicle battery (24) if, in addition, the driving speed of the hybrid motor vehicle is below a limit speed.

Images