Aircraft hybrid electric power cabin thermal management system and control method thereof

Abstract

The invention discloses an aircraft hybrid electric power cabin thermal management system and a control method thereof, and the aircraft hybrid electric power cabin thermal management system comprises an air incoming flow cooling system, a fuel oil cooling system, an air circulation cooling system, an evaporation circulation cooling system, a power battery heating system and an electric control unit. And the air incoming flow cooling system, the fuel oil cooling system, the air circulation cooling system, the evaporation circulation cooling system and the power battery heating system are in control connection with the electric control unit. According to a current flight stage and an environment temperature state, an air incoming flow cooling system, a fuel oil cooling system, an air circulation cooling system, an evaporation circulation cooling system and a power battery heating system are correspondingly controlled to heat a power battery, a lubricating oil system, a generator, a motor and an electric control unit in a hybrid electric power cabin; and the engine body is subjected to comprehensive thermal management, so that the thermal management requirements of the hybrid electric power cabin in different flight stages and environment states are met, and the hybrid electric power cabin is always in the optimal temperature state.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft thermal management, and in particular, to an aircraft hybrid-electric power cabin thermal management system and a control method thereof. Background Art

[0002] The current aircraft hybrid-electric power system uses a series architecture. After the engine generates electricity, the electric energy is allocated by the electronic control unit and then drives the motor and the propeller / wheel; the power battery, as an energy storage device, can supplement the electric energy provided by the generator to drive the propeller / wheel, or can absorb and store the excess electric energy of the generator. Compared with the traditional power system, the hybrid-electric power system has added components such as high-power motors, high-power electronic control units, and power batteries. These components need to be compactly arranged in the power cabin and will generate a large amount of heat during operation. The thermal management requirements of different components vary greatly, and the existing thermal management solutions can no longer meet the requirements (especially in high-temperature summer weather).

[0003] Although water cooling can be used for the thermal management of batteries, motors, and electronic control units, due to weight reduction reasons, water cooling is not suitable for directly applying to the thermal management of the aircraft power cabin. Another cooling method for batteries, motors, and electronic control units is air cooling, but this cooling method has poor efficiency and it is difficult to fully meet the cooling requirements of the hybrid-electric power cabin in high-temperature summer weather. The thermal management solutions mentioned in the existing published papers and patents use air cooling and oil cooling, and these thermal management solutions do not comprehensively consider the possible ways of air circulation cooling and evaporation cycle cooling of the power cabin. On the other hand, although some thermal management solutions introduce fuel cooling in the power cabin cooling, there is no specific solution for the power cabin cooling when the fuel is insufficient in the second half of the flight and during descent. Moreover, these existing thermal management solutions usually only focus on the thermal management of batteries, motors, and electronic control units, while ignoring the thermal management of the engine body, and do not consider the working characteristics of the engine in the whole thermal management solution. These existing thermal management solutions do not fully consider the different working states of the aircraft during flight. Although some thermal management solutions consider the thermal management in the takeoff / cruise / descent states, they do not fully consider the influence of the ambient temperature, nor do they consider the thermal management in special emergency states. On the other hand, these existing thermal management solutions generally adopt air cooling and open-loop cooling modes. This open-loop cooling mode has poor cooling effect when the ambient temperature is high and cannot be used in combination with evaporation cycle cooling / air circulation cooling. Summary of the Invention

[0004] The present application provides an aircraft hybrid-electric power cabin thermal management system to solve the technical problem that the existing thermal management technology cannot meet the cooling requirements of the aircraft hybrid-electric power cabin under different working conditions.

[0005] The present application is realized through the following solutions: A hybrid electric power cabin thermal management system for an aircraft, comprising an air inlet cooling system, a fuel cooling system, an air cycle cooling system, an evaporation cycle cooling system, a power battery heating system and an electronic control unit. The air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system and the power battery heating system are controlled and connected to the electronic control unit. Among them: The air inlet cooling system is connected to the power battery, the generator, the motor, the electronic control unit and the engine body for cooling; the fuel cooling system is connected to the generator, the motor, the electronic control unit and the lubricating oil system for cooling; the air cycle cooling system is connected to the power battery, the lubricating oil system, the generator, the motor, the electronic control unit and the engine body for cooling; the evaporation cycle cooling system is connected to the power battery for cooling; the power battery heating system is connected to the power battery and the engine body for heating. The electronic control unit is used to comprehensively thermally manage the power battery, the lubricating oil system, the generator, the motor, the electronic control unit and the engine body in the hybrid electric power cabin by controlling the air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system and the power battery heating system according to the current flight phase and environmental temperature state of the aircraft.

[0006] Further, the air inlet cooling system includes an air inlet, a third valve, a fourth valve, a confluence cooling air confluence port and a circulation fan connected by pipelines. The air inlet diverts a part of the incoming air after the propeller to the power battery through a pipeline via the third valve, a part to the generator, the motor and the electronic control unit via the fourth valve, and a part to the lubricating oil system and the cold end of the engine for cooling, and then converges at the confluence cooling air confluence port and is transported to the hot end of the engine to be mixed with the incoming air at the cold end of the engine to jointly cool the engine body. Subsequently, the cooling air is discharged from the power cabin together with the gas combusted and doing work in the engine body by the hot end of the engine and the circulation fan; The fuel cooling system includes a fuel pump, a fuel tank and a first radiator connected by pipelines. The fuel pump diverts the fuel in the fuel tank through a pipeline to the generator, the motor, the electronic control unit and the lubricating oil system. The cooled fuel exchanges heat through the first radiator and then returns to the fuel tank. The fuel for cooling the lubricating oil system enters the engine body for combustion and work; The air circulation cooling system includes a fifth valve, a third radiator, a cooling turbine, an eighth valve, and a seventh valve connected by pipelines. After the compressed gas in the engine body passes through the compressor bleed port, the fifth valve, the third radiator, and the cooling turbine in sequence, a part of the gas is introduced into the intake port through the eighth valve and cools the power battery, the lubricating oil system, the generator, the motor, the electronic control unit, and the engine body together with the air inflow cooling system. Another part is introduced into the power battery through the seventh valve to cool the power battery. The cooled air converges into the cooling air flow confluence port, and the cooling air flow confluence port transports the air flow to the hot end of the engine. Subsequently, the hot end of the engine and the circulation fan discharge the cooling air flow and the combustion gas in the engine body out of the power cabin together; The evaporation cycle cooling system includes a compressor, a second radiator, an expansion valve, and an evaporation cooling device connected in sequence to form a closed cycle. The evaporation cooling device is used to cool the power battery; The power battery heating system includes a sixth valve and a first valve connected by pipelines. A part of the high-temperature gas discharged from the hot end of the engine is introduced into the power battery through the sixth valve and the pipeline to heat the power battery. The heated gas converges into the cooling air flow confluence port through the first valve. The cooling air flow confluence port transports the air flow to the hot end of the engine. Subsequently, the hot end of the engine and the circulation fan discharge the cooling air flow and the combustion gas in the engine body out of the power cabin together.

[0007] Further, the second radiator is a condensation radiator.

[0008] Further, the power battery heating system further includes a heating device. One end of the heating device is connected to the power battery through a second valve, and the other end is connected to the cooling air flow confluence port.

[0009] Further, the heating device is a PCT heating device.

[0010] Further, phase change materials are arranged around the power battery.

[0011] On the other hand, this application also provides a control method for the thermal management system of an aircraft hybrid power cabin, including the steps of: S1. Obtain the current flight state and environmental temperature state of the aircraft. The flight state includes the takeoff stage, the flight cruise stage, and the special emergency state. The flight cruise stage includes the first half of the cruise and the second half of the cruise. The special emergency state includes engine power limitation and battery power limitation; the environmental temperature state includes high-temperature weather and low-temperature weather; S2. According to the current flight phase of the aircraft and the environmental temperature status, correspondingly control the air intake cooling system, fuel cooling system, air cycle cooling system, evaporative cycle cooling system, and power battery heating system to conduct comprehensive thermal management on the power battery, lubricating oil system, generator, motor, electronic control unit, and engine body in the hybrid electric power cabin.

[0012] Further, the step S2 specifically includes the steps: S21. When the current flight state and environmental temperature state are in the takeoff phase on a hot day, control the air intake cooling system and the fuel cooling system to cool the lubricating oil system, generator, motor, and electronic control unit together. The engine body is cooled by the air intake cooling system, and the power battery is cooled by the evaporative cycle cooling system. S22. When the current flight state and environmental temperature state are in the takeoff phase on a cold day, control the air intake cooling system and the fuel cooling system to cool the lubricating oil system, generator, motor, and electronic control unit together. The engine body is cooled by the air intake cooling system. The power battery controls cooling or heating according to the flight conditions and temperature threshold. If the power battery needs to be cooled, control the air intake cooling system to cool it. If the power battery needs to be heated, control the power battery heating system to heat it.

[0013] Further, the step S2 specifically further includes the steps: S23. When the current flight state is the first half of the cruise, control the air intake cooling system and the fuel cooling system to cool the lubricating oil system, generator, motor, and electronic control unit together. The engine body is cooled by the air intake cooling system. The power battery controls cooling or heating according to the flight conditions and temperature threshold. If the power battery needs to be cooled, control the air intake cooling system to cool it. If the power battery needs to be heated, control the power battery heating system to heat it. The air cycle cooling system selects to be put into use to cool the lubricating oil system, generator, motor, electronic control unit, engine body, and power battery according to the flight condition requirements. S24. When the current flight state is the second half of the cruise, control the air intake cooling system, fuel cooling system, and air cycle cooling system to cool the lubricating oil system, generator, motor, and electronic control unit together. The power battery correspondingly selects the evaporative cycle cooling system, air cycle cooling system, or air intake cooling system for cooling according to the environmental temperature and engine operating state.

[0014] Further, the step S2 specifically further includes the steps: S25. If the current flight state is when the engine power is limited, control the air inflow cooling system and the fuel cooling system to cool the lubricating oil system, the generator, the motor, and the electronic control unit together. The engine body is cooled by the air inflow cooling system, and the power battery is cooled by one or more of the air inflow cooling system, the air cycle cooling system, and the phase change material cooling; S26. If the current flight state is when the battery power is limited, turn off the air cycle cooling system and the evaporation cycle cooling system, and control the air inflow cooling system and the fuel cooling system to cool the lubricating oil system, the generator, the motor, and the electronic control unit together. The power battery and the engine body are cooled by the air inflow cooling system.

[0015] Compared with the prior art, the present application has the following beneficial effects: The present application provides an aircraft hybrid electric power cabin thermal management system and its control method. The system includes an air inflow cooling system, a fuel cooling system, an air cycle cooling system, an evaporation cycle cooling system, a power battery heating system, and an electronic control unit. The electronic control unit can correspondingly control the air inflow cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system to perform comprehensive thermal management on the power battery, the lubricating oil system, the generator, the motor, the electronic control unit, and the engine body in the hybrid electric power cabin, meeting the thermal management requirements of the hybrid electric power cabin in different flight stages and different environmental states, and enabling the hybrid electric power cabin to always be in the best temperature state according to different flight stages and environmental temperature states; by controlling the air inflow cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system, the present application can make the cooling of the power battery of the aircraft include two forms: closed-loop and open-loop. When the environmental temperature is high, the closed-loop evaporation cycle cooling system is used for cooling; when the environmental temperature is low, open-air cooling is adopted, that is, the air inflow cooling system and the air cycle cooling system enable the battery compartment to always obtain better cooling efficiency, meeting the cooling requirements under different environmental temperatures. The present application introduces the air cycle cooling system, improves the overall cooling efficiency of the system, and reduces the energy waste caused by the need to discharge a large amount of gas to prevent surge in the engine. In addition, the present application can also effectively manage the heat in the hybrid electric power cabin in two emergency situations: engine power limitation and battery limitation.

[0016] In addition to the purposes, features, and advantages described above, the present application has other purposes, features, and advantages. The following will refer to the drawings to further elaborate on the present application in detail. Description of the Drawings

[0017] The accompanying drawings, which form a part of this application, are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings: Figure 1 is a schematic diagram of the principle of the hybrid electric power cabin thermal management system of the aircraft in the preferred embodiment of the present invention; Figure 2 is a schematic diagram of the control method flow of the hybrid electric power cabin thermal management system of the aircraft in the preferred embodiment of the present invention; Figure 3 is a schematic diagram of the working principle of the thermal management system for takeoff in high temperature weather in the preferred embodiment of the present invention; Figure 4 is a schematic diagram of the working principle of the thermal management system for takeoff in low temperature weather in the preferred embodiment of the present invention; Figure 5 is a schematic diagram of the working principle of the thermal management system in the second half of the cruise in the preferred embodiment of the present invention; Figure 6 is a schematic diagram of the working principle of the thermal management system with limited engine power in the preferred embodiment of the present invention; Figure 7 is a schematic diagram of the working principle of the thermal management system with limited battery power in the preferred embodiment of the present invention; Figure 8 is a schematic diagram of the working principle of the preheating mode in the preferred embodiment of the present invention.

[0018] In the figure: 1, fuel tank; 2, first radiator; 3, lubricating oil system; 4, fuel pump; 5, heating device; 6, cooling air flow confluence port; 7, first valve; 8, second valve; 9, power battery; 10, evaporative cooling device; 11, air inlet; 12, expansion valve; 13, second radiator; 14, compressor; 15, third valve; 16, fourth valve; 17, electronic control unit; 18, motor; 19, generator; 20, hot end of the engine; 21, cold end of the engine; 22, circulation fan; 23, fifth valve; 24, sixth valve; 25, third radiator; 26, cooling turbine; 27, seventh valve; 28, eighth valve. Detailed Embodiments

[0019] The embodiments of this application will be described in detail below with reference to the accompanying drawings. However, this application can be implemented in many different ways defined and covered by the following.

[0020] As Figure 1As shown in the figure, a preferred embodiment of the present application provides a thermal management system for a hybrid electric power cabin of an aircraft, including an air inlet cooling system, a fuel cooling system, an air cycle cooling system, an evaporation cycle cooling system, a power battery heating system, and an electronic control unit 17. The air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system are controlled and connected to the electronic control unit. Among them: The air inlet cooling system is connected to the power battery 9, the generator 19, the motor 18, the electronic control unit 17, and the engine body for cooling; the fuel cooling system is connected to the generator 19, the motor 18, the electronic control unit 17, and the lubricating oil system 3 for cooling; the air cycle cooling system is connected to the power battery 9, the lubricating oil system 3, the generator 19, the motor 18, the electronic control unit 17, and the engine body for cooling; the evaporation cycle cooling system is connected to the power battery 9 for cooling; the power battery heating system is connected to the power battery 9 and the engine body for heating. The electronic control unit is used to comprehensively thermally manage the power battery 9, the lubricating oil system 3, the generator 19, the motor 18, the electronic control unit 17, and the engine body in the hybrid electric power cabin according to the current flight stage and environmental temperature state of the aircraft.

[0021] Preferably, the air inlet cooling system includes an air inlet 11, a third valve 15, a fourth valve 16, a confluence cooling air confluence port 6, and a circulation fan 22 connected by pipelines. The air inlet 11 diverts a part of the incoming air after the propeller to the power battery 9 through a pipeline, a part to the generator 19, the motor 18, and the electronic control unit 17 through the fourth valve 16, and a part to the lubricating oil system 3 and the cold end 21 of the engine for cooling, and then converges at the confluence cooling air confluence port 6 and is transported to the hot end 20 of the engine to be mixed with the incoming air from the cold end 21 of the engine to cool the engine body together. Subsequently, the cooling air is discharged from the power cabin together with the combustion gas in the engine body by the hot end 20 of the engine and the circulation fan 22; The fuel cooling system includes a fuel pump 4 and a fuel tank 1, a first radiator 2 connected by pipelines. The fuel pump 4 diverts the fuel in the fuel tank 1 through a pipeline to the generator 19, the motor 18, the electronic control unit 17, and the lubricating oil system 3. After cooling, the fuel exchanges heat through the first radiator 2 and then returns to the fuel tank 1. The fuel for cooling the lubricating oil system 3 enters the engine body for combustion work; The air circulation cooling system includes a fifth valve 23, a third radiator 25, a cooling turbine 26, an eighth valve 28, and a seventh valve 27 connected by pipelines. The compressed gas in the engine body is successively led through the compressor bleed port, the fifth valve 23, the third radiator 25, and the cooling turbine 26. Then, a part of it is introduced into the intake port 11 through the eighth valve 28 to cool the power battery 9, the lubricating oil system 3, the generator 19, the motor 18, the electronic control unit 17, and the engine body together with the air inflow cooling system. Another part is led into the power battery through the seventh valve 27 to cool the power battery. The cooled air converges at the cooling air flow confluence port 6, and the cooling air flow confluence port 6 transports the air flow to the hot end 20 of the engine. Subsequently, the hot end 20 of the engine and the circulation fan 22 discharge the cooling air flow and the combustion gas in the engine body out of the power compartment together; The evaporation cycle cooling system includes a compressor 14, a second radiator 13, an expansion valve 12, and an evaporation cooling device 10 connected in sequence to form a closed cycle. The evaporation cooling device 10 is used to cool the power battery 9; The power battery heating system includes a sixth valve 24 and a first valve 7 connected by pipelines. A part of the high-temperature gas discharged from the hot end 20 of the engine is introduced into the power battery 9 through the sixth valve 24 and the pipeline to heat the power battery 9. The heated gas converges at the cooling air flow confluence port 6 through the first valve 7. The cooling air flow confluence port 6 transports the air flow to the hot end 20 of the engine. Subsequently, the hot end 20 of the engine and the circulation fan 22 discharge the cooling air flow and the combustion gas in the engine body out of the power compartment together.

[0022] Among them, the second radiator 13 is a condensation radiator.

[0023] Among them, the power battery heating system further includes a heating device 5. One end of the heating device 5 is connected to the power battery 9 through a second valve 8, and the other end is connected to the cooling air flow confluence port 6. The heating device 5 is a PCT heating device.

[0024] Phase change materials, such as paraffin phase change materials, are arranged around the power battery 9.

[0025] The air flow of the air inflow cooling system, the fuel flow of the fuel cooling system, and the air flow of the air circulation cooling system are controlled by the electronic control unit 17. Flow regulating valves are respectively arranged on the pipelines of the air inflow cooling system, the fuel cooling system, and the air circulation cooling system. Each flow regulating valve is electrically connected to the electronic control unit. The electronic control unit 17 adjusts the air flow of the air inflow cooling system, the fuel flow of the fuel cooling system, and the air flow of the air circulation cooling system by controlling the opening degree of each flow regulating valve, so as to further control the cooling speed of each cooling system to meet the thermal management requirements under corresponding working conditions.

[0026] In the above embodiments, the cooling methods of the hybrid electric power cabin of the aircraft include air inlet cooling, fuel cooling, air cycle cooling, and evaporation cycle cooling. Air inlet cooling uses the air after the propeller for cooling. Fuel cooling uses the fuel in the fuel tank for cooling. Air cycle cooling uses a large amount of compressed gas led out from the engine, and these compressed gases are depressurized and cooled in the turbine of the environmental control system. The evaporation cycle cooling principle is similar to that of a common air conditioner, including a compressor 14, a condenser, an evaporator, an expansion valve 12, etc., and electric energy is consumed to achieve the cooling cycle.

[0027] In order to effectively manage the heat of different components of the hybrid electric power cabin, the above embodiments manage the power cabin in a partitioned manner, including a high-temperature area (engine), a medium-temperature area (motor and electronic control unit), and a power battery (low-temperature area). The generator and the motor are collectively referred to as the motor. The engine lubricating oil system uses fuel cooling and air cooling, and the motor and the electronic control unit are also cooled by fuel and air. The main heat management requirements of the electronic control unit come from power electronic power devices such as IGBT / SiC; the battery management unit, the engine control unit, and the aircraft control unit usually have independent cooling designs and relatively small cooling requirements, which are not involved in this technical solution.

[0028] When the temperature of the power battery 9 is high, the risk of its thermal runaway is very high. When the temperature is low, the charge and discharge capacity of the power battery drops significantly. The cooling methods of the power battery include air inlet cooling, fuel cooling, air cycle cooling, and evaporation cycle forced cooling, which are flexibly selected according to the flight conditions.

[0029] The cooling of the lubricating oil system, the motor, and the electronic control unit adopts an open cycle. After the air enters the power cabin, it first cools the above-mentioned equipment and is finally ejected and discharged in the exhaust device.

[0030] The air cooling of the power battery includes an open cycle and a closed evaporation cycle; when the air temperature is low, an open air cycle is adopted; when the ambient temperature is high, a closed evaporation cycle cooling is adopted. If the above methods still cannot fully meet the cooling requirements of the power battery, the temperature of the battery pack rises to the melting point of the paraffin phase change material (about 42 degrees Celsius), and the paraffin around the battery can absorb a large amount of heat, effectively preventing thermal runaway.

[0031] A thermal management system for a hybrid electric power cabin of an aircraft provided in the above embodiment includes an air inlet cooling system, a fuel cooling system, an air cycle cooling system, an evaporation cycle cooling system, a power battery heating system, and an electronic control unit 17. The electronic control unit 17 can correspondingly control the air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system to perform comprehensive thermal management on the power battery 9, the lubricating oil system 3, the generator 19, the motor 18, the electronic control unit 17, and the engine body in the hybrid electric power cabin, so as to meet the thermal management requirements of the hybrid electric power cabin in different flight stages and different environmental states, and keep the hybrid electric power cabin in the best temperature state according to different flight stages and environmental temperature states; By controlling the air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system, the power battery cooling of the aircraft can include two forms: closed-loop and open-loop. When the environmental temperature is high, the closed-loop evaporation cycle cooling system is used for cooling; When the environmental temperature is low, open-air cooling is adopted, that is, the air inlet cooling system and the air cycle cooling system enable the battery compartment to always obtain better cooling efficiency and meet the cooling requirements under different environmental temperatures. The air cycle cooling system is introduced in this application to improve the overall cooling efficiency of the system and reduce the energy waste caused by the large amount of gas that needs to be discharged by the engine to prevent surge. In addition, this embodiment can also effectively manage the heat in the hybrid electric power cabin in two emergency situations: engine power limitation and battery limitation.

[0032] As Figure 2 shown, another preferred embodiment of this application also provides a control method for a thermal management system of a hybrid electric power cabin of an aircraft, including the steps: S1. Obtain the current flight state and environmental temperature state of the aircraft. The flight state includes a takeoff stage, a flight cruise stage, and a special emergency state. The flight cruise stage includes the first half of the cruise and the second half of the cruise. The special emergency state includes engine power limitation and battery power limitation; The environmental temperature state includes high-temperature weather and low-temperature weather; S2. Correspondingly control the air inlet cooling system, the fuel cooling system, the air cycle cooling system, the evaporation cycle cooling system, and the power battery heating system to perform comprehensive thermal management on the power battery 9, the lubricating oil system 3, the generator 19, the motor 18, the electronic control unit 17, and the engine body in the hybrid electric power cabin according to the current flight stage and environmental temperature state of the aircraft.

[0033] This embodiment provides a control method for the thermal management system of an aircraft hybrid-electric power cabin. This method finely controls the thermal management of the aircraft hybrid-electric power cabin in segments, and different thermal management strategies are adopted in the takeoff phase, flight phase, and descent phase. Both the ambient temperature and the fuel tank level of the aircraft will affect the thermal management strategy. Among them, after obtaining the current flight state and ambient temperature state of the aircraft, the electronic control unit 17 can correspondingly control the air intake cooling system, fuel cooling system, air cycle cooling system, evaporation cycle cooling system, and power battery heating system to comprehensively manage the thermal management of the power battery 9, lubricating oil system 3, generator 19, motor 18, electronic control unit 17, and engine body in the hybrid-electric power cabin, meeting the thermal management requirements of the hybrid-electric power cabin in different flight phases and different environmental states, and enabling the hybrid-electric power cabin to always be in the best temperature state according to different flight phases and ambient temperature states; this embodiment can also effectively manage the thermal management in the hybrid-electric power cabin in two emergency situations of engine power limitation and battery limitation.

[0034] In a preferred embodiment of the present application, the step S2 specifically includes the steps: S21. When the current flight state and ambient temperature state are the takeoff phase in high-temperature weather, control the air intake cooling system and the fuel cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The engine body is cooled through the air intake cooling system, and the power battery 9 is cooled through the evaporation cycle cooling system; S22. When the current flight state and ambient temperature state are the takeoff phase in low-temperature weather, control the air intake cooling system and the fuel cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The engine body is cooled through the air intake cooling system; the power battery 9 controls cooling or heating according to the flight condition and temperature threshold. If the power battery 9 needs to be cooled, control the air intake cooling system to cool it. If the power battery 9 needs to be heated, control the power battery heating system to heat it.

[0035] This embodiment mainly relates to the thermal management control in the takeoff phase, where: Step S21 mainly aims at the takeoff phase in high-temperature weather (in the airworthiness regulations, the air temperature is 30°C - 45°C, and some models are required to adapt to high-temperature environments above 55°C). In this takeoff phase, the power demand of the aircraft is very large, and the engine power drops significantly in a high-temperature environment. At this time, the power of the aircraft is provided jointly by the power battery 9 and the gas turbine engine, and the power provided by the power battery increases. The cooling requirements of the engine, generator 19, power battery 9, electronic control unit 17, and motor 18 are all very large. At this time, simple air intake cooling cannot meet the cooling requirements of the power cabin.

[0036] The thermal management strategy for the above situation is as follows Figure 3 As shown, in this embodiment, an evaporation cycle cooling system is used to cool the important and sensitive power battery 9. At this time, the eighth valve 28, the seventh valve 27, the third valve 15, the fifth valve 23, the sixth valve 24, the second valve 8, and the first valve 7 are closed, and the fourth valve 16 is opened.

[0037] After the fuel comes out of the fuel tank 1, it is used to cool the motor and the electronic control unit 17, and then returns to the fuel tank 1; the fuel circulation flow rate is adjusted according to the temperature of the motor (or the electronic control unit). When the temperature is high, the rotation speed of the fuel pump 4 is increased to increase the fuel cooling flow rate. The fuel cooling combined with the incoming air flow cooling can meet the cooling requirements of the motor and the electronic control unit 17, and part of the heat of the heated fuel is exchanged to the atmospheric environment through the first radiator 2.

[0038] When the temperature in summer high-temperature weather may be greater than the target temperature of the power battery 9 (20°C - 30°C), the power battery 9 is wrapped in a closed battery compartment, and evaporation cycle cooling is used to exchange heat to the atmospheric environment through the second radiator 13.

[0039] Part of the incoming air flow behind the propeller enters the cold end 21 of the engine to provide intake air and cold end cooling for the engine; part of it is used to cool the lubricating oil system 3, the generator 19, the motor 18, and the electronic control unit 17. The cooling gas is introduced into the hot end 20 of the engine to take away the heat of the hot end 20 of the engine and prevent the engine compartment and the surrounding environment from overheating.

[0040] Step S22 mainly targets the takeoff stage in low-temperature weather (usually referring to the atmospheric environment temperature of -20°C to -40°C). In extremely cold weather, the hybrid electric system needs to be preheated before takeoff before the engine starts. The preheating principle is shown in Figure 8 . At this time, the third valve 15, the fourth valve 16, the sixth valve 24, and the second valve 8 are opened, and the eighth valve 28, the seventh valve 27, the fifth valve 23, and the first valve 7 are closed.

[0041] In low-temperature weather, the power reserve of the engine increases significantly, and the power provided by the power battery 9 decreases significantly. Even the power battery 9 can work without discharging. The cooling requirements of the engine 20, generator 19, power battery 9, electronic control unit 17, and motor 18 are all reduced. Among them, the power battery 9 may also need to be appropriately heated (depending on the deviation between the power battery temperature and the thermal management target temperature. For example, when the power battery temperature is below 10°C, the power battery is heated). In low-temperature weather, the air inflow capacity is very strong, and the fuel internal circulation flow rate and air inflow flow rate can be further adjusted downward (depending on the lubricating oil temperature, motor / electronic control unit temperature, and fuel temperature. The adjustment measures are different in different situations. For example, when the motor temperature is below 60°C, and the inlet fuel temperature of the aeroengine is below 10°C, and the lubricating oil and electronic control unit temperatures are normal, the fuel internal circulation flow rate of the motor cooling flow path can be increased, and the air inflow flow rate of the motor cooling flow path can be decreased, so as to maintain both the motor temperature and the fuel inlet temperature in a suitable range).

[0042] The thermal management strategy for the above situation is as Figure 4 shown. At this time, the seventh valve 27, eighth valve 28, fifth valve 23, and valve 8 are closed, and the third valve 15, fourth valve 16, sixth valve 24, and first valve 7 are opened. The suitable operating temperature of the power battery 9 is generally below 40 degrees Celsius. Since the exhaust gas temperature of the engine is relatively high, usually around 300 to 600 degrees Celsius, it cannot be directly used to heat the power battery 9. It needs to be mixed with the air inflow to a suitable temperature before it can be used for battery heating. The air inflow cooling system and the fuel cooling system cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The engine is cooled through the air inflow cooling system; the power battery 9 controls cooling or heating according to the flight condition and temperature threshold. If the power battery 9 needs cooling, it is cooled by the air inflow cooling system. If the power battery needs heating, it is heated by the power battery heating system to ensure that the power battery 9 is always at a suitable operating temperature.

[0043] In a preferred embodiment of the present application, the step S2 specifically further includes the steps of: S23. If the current flight state is the first half of the cruise, control the air inflow cooling system and the fuel cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The engine body is cooled through the air inflow cooling system; the power battery 9 controls cooling or heating according to the flight condition and temperature threshold. If the power battery 9 needs cooling, control the air inflow cooling system to cool it. If the power battery needs heating, control the power battery heating system to heat it; the air circulation cooling system selects to cool the lubricating oil system 3, generator 19, motor 18, electronic control unit 17, engine body, and power battery 9 according to the flight condition requirements; S24. When the current flight state is the second half of the cruise, control the air inflow cooling system, fuel cooling system, and air cycle cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The power battery 9 selects the evaporation cycle cooling system, air cycle cooling system, or air inflow cooling system for cooling according to the ambient temperature and engine operating state.

[0044] This embodiment mainly relates to the thermal management control during the cruise phase, where: Step S23 mainly targets the thermal management in the first half of the cruise. When the aircraft is cruising in the air, the power consumption is generally small. The power battery 9, as an energy storage component, adjusts the operating state of the engine, and the charge and discharge current is small. The cooling requirements of the engine, generator 19, power battery 9, electronic control unit 17, and motor 18 are all reduced.

[0045] The thermal management strategy for the above situation in the first half of the cruise is as follows: Since the cooling capacity of the air inflow is usually strong, combined with the fuel internal circulation cooling, it can meet the cooling requirements of the lubricating oil system 3, motor 18, generator 19, and electronic control unit 17. At this time, the charge and discharge environment of the power battery 9 is relatively mild, and the thermal management strategy needs to be selected according to the temperature of the power battery 9. If the power battery 9 does not work for a long time, the cooling of the power battery 9 should be stopped, and if the temperature is too low, the power battery 9 needs to be heated. If the power battery 9 has a sharp temperature rise due to high-power charge and discharge at some times, the power battery 9 should be cooled at this time. If the power battery 9 needs to be cooled, it is cooled by the air inflow cooling system, and if the power battery 9 needs to be heated, it is heated by the power battery heating system. The specific cooling method can be selected according to the needs Figures 3 to 7 of the type in.

[0046] Step S24 mainly targets the thermal management in the second half of the cruise. In the second half of the flight (including the aircraft landing process), the fuel of the aircraft is continuously consumed, and the fuel available for cooling the motor and electronic control unit 17 is continuously reduced. At the same time, the temperature of the fuel tank 1 continuously rises during the fuel cooling process, which makes the cooling capacity of the fuel continuously decline. In situations such as aircraft landing and takeoff again, emergency, and acceleration, the motor and electronic control unit 17 may generate a large amount of heat, so the demand for cooling the motor and electronic control unit 17 exists for a long time. Especially in summer when the temperature is high, relying solely on air inflow and fuel cooling in the second half of the flight may not be able to meet the cooling requirements of the motor 18, generator 19, and electronic control unit 17.

[0047] The thermal management strategy for the above situation in the second half of the cruise is as Figure 5 shown. At this time, the eighth valve 28, fourth valve 16, and fifth valve 23 are opened, and the seventh valve 27, third valve 15, sixth valve 24, second valve 8, and first valve 7 are closed.

[0048] For example, in the second half of the summer cruise, evaporative cycle cooling and air cycle cooling are introduced. The incoming air cooling system, fuel cooling system, and air cycle cooling system together cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17. The engine body is cooled by the incoming air cooling system and air cycle cooling system, and the power battery 9 is cooled by selecting the evaporative cycle cooling system.

[0049] Considering that the engine may operate at a low power state during low-altitude cruise, the engine usually needs to discharge a large amount of gas to prevent surge. These gases can be collected and used for air cycle cooling, thereby improving the overall cooling efficiency of the system.

[0050] In a preferred embodiment of the present application, the step S2 specifically further includes the steps of: S25. If the current flight state is that the engine power is limited, control the incoming air cooling system and fuel cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together. The engine body is cooled by the incoming air cooling system, and the power battery 9 is cooled by one or more of the incoming air cooling system, air cycle cooling system, and phase change material cooling; S26. If the current flight state is that the battery power is limited, turn off the air cycle cooling system and evaporative cycle cooling system, control the incoming air cooling system and fuel cooling system to cool the lubricating oil system 3, generator 19, motor 18, and electronic control unit 17 together, and the power battery 9 and the engine body are cooled by the incoming air cooling system.

[0051] This embodiment mainly relates to the thermal management control in special emergency states, where: Step S25 mainly aims at the thermal management when the engine power is limited. In some cases, the engine may have an in-air failure and can only be used with reduced power. At this time, the power battery 9 needs to discharge at a high power within a short time during the descent, and the total power of the motor may slightly decrease and safely descend within a short time. In this case, the heat dissipation and cooling requirements of the power battery 9 increase significantly, the cooling requirements of the motor and electronic control unit 17 remain relatively unchanged, and the power that the entire power system can provide decreases significantly.

[0052] A thermal management strategy for the above situation of engine power limitation is as follows: The generator 19, the motor 18, and the electronic control unit 17 are cooled by the fuel and air flow. The cooling of the power battery 9 can be selected from one or several of the air flow cooling, air circulation cooling, and paraffin phase change material cooling. The possible cooling combinations include but are not limited to the following methods: When the ambient temperature is very low (below 10°C), only air flow cooling is required; when the ambient temperature is relatively high (above 30°C), air circulation cooling and paraffin phase change cooling are required (the principle is shown in Figure 6 ), and the paraffin phase change material is arranged around the power battery 9; when the ambient temperature is moderate (10°C - 30°C), air flow cooling and air circulation cooling are used.

[0053] Such as Figure 6 shown, when the ambient temperature is relatively high, the cooling method of the power battery 9 is as follows: The eighth valve 28, the third valve 15, the sixth valve 24, and the second valve 8 are closed, and the seventh valve 27, the fourth valve 16, the fifth valve 23, and the first valve 7 are opened. The power battery 9 uses air circulation cooling and paraffin phase change cooling.

[0054] In this situation of engine power limitation, a relatively large amount of compressed gas still needs to be discharged to prevent surging, and this compressed gas can be used for air circulation cooling.

[0055] Step S26 is mainly for the thermal management of battery power limitation. In another special case, a part of the power battery 9 fails (to ensure safety, the power battery 9 is designed so that if a part breaks, the other parts can still be used). The high-power use of the remaining part of the power battery 9 is also limited. In this case, the cooling demand of the power battery 9 weakens, and the cooling capacity of the motor and the electronic control unit 17 remains relatively unchanged. At this time, the engine needs to operate at a high power state, and the aircraft power demand is relatively large, and air circulation cooling and evaporation cycle cooling are not provided.

[0056] The thermal management strategy for the above situation of battery power limitation is as Figure 7 shown. The seventh valve 27, the eighth valve 28, the fifth valve 23, the sixth valve 24, and the second valve 8 are closed, and the first valve 7, the third valve 15, and the fourth valve 16 are opened. The air flow cooling system and the fuel cooling system together cool the lubricating oil system 3, the generator 19, the motor 18, and the electronic control unit 17. The power battery 9 and the engine body are cooled by the air flow cooling system.

[0057] The existing invention adopts an open-loop cooling mode, and this open-loop cooling mode has poor cooling performance when the ambient temperature is relatively high. The battery compartment cooling of the present invention includes two forms: closed-loop and open-loop. When the ambient temperature is relatively high, closed-loop evaporation cycle cooling is adopted; when the ambient temperature is relatively low, open-air cooling is adopted, so that the battery compartment can always obtain better cooling efficiency.

[0058] During cruising of the existing invention, the engine usually operates at a low power state. The engine usually needs to discharge a large amount of gas to prevent surging, which results in energy waste. The present invention introduces a cooling turbine and air cycle cooling to improve the overall cooling efficiency of the system.

[0059] The existing solution does not consider the thermal management in special emergency situations. The present invention has developed a special thermal management strategy for two emergency situations: engine power limitation and battery limitation, further improving the applicability of thermal management.

[0060] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0061] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A thermal management system for a hybrid electric power cabin of an aircraft, characterized in that: The invention comprises an air flow cooling system, a fuel cooling system, an air circulation cooling system, an evaporative circulation cooling system, a power battery heating system and an electronic control unit (17), wherein the air flow cooling system, the fuel cooling system, the air circulation cooling system, the evaporative circulation cooling system, the power battery heating system and the electronic control unit are control-connected, wherein: The air flow cooling system is connected to the power battery (9), the generator (19), the motor (18), the electronic control unit (17) and the engine body for cooling; the fuel cooling system is connected to the generator (19), the motor (18), the electronic control unit (17) and the lubricating oil system (3) for cooling; the air circulation cooling system is connected to the power battery (9), the lubricating oil system (3), the generator (19), the motor (18), the electronic control unit (17) and the engine body for cooling; the evaporative circulation cooling system is connected to the power battery (9) for cooling; the power battery heating system is connected to the power battery (9) and the engine body for heating, and the electronic control unit is used to control the air flow cooling system, the fuel cooling system, the air circulation cooling system, the evaporative circulation cooling system and the power battery heating system according to the current flight stage of the aircraft and the ambient temperature state to perform comprehensive thermal management on the power battery (9), the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17) and the engine body in the hybrid power cabin.

2. The aircraft hybrid electric power cabin thermal management system according to claim 1, characterized in that: The air flow cooling system comprises an air intake (11), a third valve (15), a fourth valve (16), a cooling air flow confluence port (6), and a circulating fan (22) connected by pipelines. The air intake (11) diverts part of the air flow behind the propeller through the pipeline to the power battery (9) through the third valve (15), diverts part of the air flow through the fourth valve (16) to the generator (19), the motor (18) and the electronic control unit (17), and diverts part of the air flow to the lubricating oil system (3) and the cold end (21) of the engine for cooling before confluence with the cooling air flow confluence port (6) to be transported to the hot end (20) of the engine and the engine. The incoming air from the cold end (21) is mixed to cool the engine body together, and then the cooling air flow is discharged from the power compartment together with the combustion gas in the engine body by the hot end (20) of the engine and the circulating fan (22); the fuel cooling system comprises a fuel pump (4), a fuel tank (1), and a first radiator (2) connected by pipelines; the fuel pump (4) diverts the fuel in the fuel tank (1) through pipelines to the generator (19), the motor (18), the electronic control unit (17), and the lubricating oil system (3); the fuel after cooling is returned to the fuel tank (1) after heat exchange in the first radiator (2), and the fuel in the lubricating oil system (3) is cooled. The oil enters the engine body for combustion and work; the air circulation cooling system comprises a fifth valve (23), a third radiator (25), a cooling turbine (26), an eighth valve (28), and a seventh valve (27) connected by pipelines, and the compressed gas in the engine body is sequentially introduced into the air inlet (11) through the eighth valve (28) after passing through the compressor rear air inlet, the fifth valve (23), the third radiator (25), and the cooling turbine (26), and a part of the compressed gas in the engine body is introduced into the air inlet (11) together with the air inlet cooling system to cool the power battery (9), the lubricating oil system (3), the generator (19), the motor (18), the electronic control unit (17), and the engine body. The other part is introduced into the power battery through the seventh valve (27) to cool the power battery, and the cooled air is merged into the cooling air flow confluence port (6), and the cooling air flow confluence port (6) conveys the air flow to the hot end (20) of the engine, and then the hot end (20) of the engine and the circulating fan (22) discharge the cooling air flow together with the combustion gas in the engine body out of the power compartment; the evaporative cycle cooling system comprises a compressor (14), a second radiator (13), an expansion valve (12), and an evaporative cooling device (10) which are sequentially connected to form a closed cycle, and the evaporative cooling device (10) is used to cool the power battery (9);The power battery heating system comprises a sixth valve (24) and a first valve (7) connected by a pipeline. A portion of the high-temperature gas discharged from the hot end (20) of the engine is introduced into the power battery (9) through the sixth valve (24) and the pipeline to heat the power battery (9). The heated gas is merged into the cooling air flow confluence port (6) through the first valve (7). The cooling air flow confluence port (6) conveys the air flow to the hot end (20) of the engine. Subsequently, the cooling air flow is discharged from the power compartment together with the combustion gas in the engine body by the hot end (20) of the engine and the circulating fan (22).

3. The aircraft hybrid electric power cabin thermal management system according to claim 2, characterized in that: The second radiator (13) is a condensing radiator.

4. The aircraft hybrid electric power cabin thermal management system according to claim 2, characterized in that: The power battery heating system also includes a heating device (5), one end of the heating device (5) is connected to the power battery (9) via a second valve (8), and the other end is connected to the cooling air flow confluence port (6).

5. The aircraft hybrid electric power cabin thermal management system according to claim 4, characterized in that: The heating device (5) is a PCT heating device.

6. The aircraft hybrid electric power cabin thermal management system according to claim 2, characterized in that: Phase change material is arranged around the power battery (9).

7. A control method for a thermal management system of an aircraft hybrid electric power cabin according to any one of claims 1 to 6, characterized in that: Includes steps: S1. Acquire the current flight status and ambient temperature status of the aircraft, wherein the flight status includes the take-off phase, the flight cruise phase, and the special emergency state, wherein the flight cruise phase includes the first half of the cruise and the second half of the cruise, and the special emergency state includes engine power limitation and battery power limitation; the ambient temperature status includes high temperature weather and low temperature weather; S2. According to the current flight stage of the aircraft and the ambient temperature state, the air flow cooling system, the fuel cooling system, the air circulation cooling system, the evaporative circulation cooling system, and the power battery heating system are controlled accordingly to perform comprehensive thermal management on the power battery (9), the lubricating oil system (3), the generator (19), the motor (18), the electronic control unit (17), and the engine body in the hybrid power cabin.

8. The control method according to claim 7, characterized in that: The step S2 specifically includes the following steps: S21. If the current flight state and the ambient temperature state are at the high temperature weather take-off stage, the air flow cooling system and the fuel cooling system are controlled to cool the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17) together, the engine body is cooled by the air flow cooling system, and the power battery (9) is cooled by the evaporative cycle cooling system; S22. If the current flight state and the ambient temperature state are at the low-temperature takeoff stage, the air flow cooling system and the fuel cooling system are controlled to cool the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17), and the engine body is cooled by the air flow cooling system; the power battery (9) is controlled to be cooled or heated according to the flight conditions and the temperature threshold. If the power battery (9) needs to be cooled, the air flow cooling system is controlled to cool it; if the power battery (9) needs to be heated, the power battery heating system is controlled to heat it.

9. The control method according to claim 8, characterized in that: The step S2 further comprises the steps of: S23, if the current flight state is the first half of the cruise, the air flow cooling system and the fuel cooling system are controlled to cool the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17), and the engine body is cooled by the air flow cooling system; the power battery (9) is controlled to be cooled or heated according to the flight conditions and the temperature threshold, if the power battery (9) needs to be cooled, the air flow cooling system is controlled to cool it, and if the power battery needs to be heated, the power battery heating system is controlled to heat it; the air circulation cooling system is selected to cool the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17), the engine body and the power battery (9) according to the flight conditions; S24. If the current flight state is the second half of the cruise, the air flow cooling system, the fuel cooling system, and the air circulation cooling system are controlled to cool the lubricating oil system (3), the generator (19), the motor (18), and the electronic control unit (17). The power battery (9) is cooled by the evaporative circulation cooling system, the air circulation cooling system, or the air flow cooling system according to the ambient temperature and the engine working state.

10. The control method according to claim 8, characterized in that: The step S2 further comprises the steps of: S25. If the current flight state is that the engine power is limited, the air flow cooling system and the fuel cooling system are controlled to cool the lubricating oil system (3), the generator (19), the motor (18) and the electronic control unit (17) together, the engine body is cooled by the air flow cooling system, and the power battery (9) is cooled by one or more cooling methods selected from the group consisting of the air flow cooling system, the air circulation cooling system and the phase change material cooling; S26. If the current flight state is that the battery power is limited, the air circulation cooling system and the evaporative circulation cooling system are turned off, and the air flow cooling system and the fuel cooling system are controlled to cool the lubricating oil system (3), the generator (19), the electric motor (18) and the electronic control unit (17) together, and the power battery (9) and the engine body are cooled by the air flow cooling system.

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