Hydrogen hybrid propulsion system low-compensation heat management method for maintaining efficient work of electric components

Abstract

The invention discloses a hydrogen hybrid propulsion system low-compensation heat management method for keeping efficient work of electric components, which uses liquid hydrogen as a terminal heat sink, and aims at solving the problem that the efficiency of the electric components such as a motor and a fuel cell is sensitive to temperature according to respective optimal working temperature intervals. Meanwhile, actual heat production states and flight mission profile changes of the electric components are considered, a heat energy dump peak shifting utilization strategy and thermal response flow control strategy cooperation mechanism is constructed, the flow of an intermediate cooling working medium is dynamically adjusted, and stage heat storage and release are implemented, so that the electric components maintain efficient operation in the whole mission process, excessive heat exchange of the system is avoided, and the service life of the system is prolonged. Therefore, the overall efficiency is improved and the fuel consumption is reduced. According to the efficient energy management method for the aviation hydrogen hybrid propulsion system, the structural weight of thermal management and compensation of the cooling capacity are effectively reduced, and the efficient energy management method for the aviation hydrogen hybrid propulsion system is efficient.

Description

Technical Field

[0001] This invention belongs to the field of aircraft thermal management technology, and particularly relates to a low-compensation thermal management method for a hydrogen hybrid propulsion system that maintains the efficient operation of electrical components. Background Technology

[0002] Hydrogen, as a clean energy carrier, has great potential for application in aircraft propulsion systems. It can not only serve as a zero-carbon emission fuel, but also as a highly efficient heat sink.

[0003] In hybrid-electric propulsion aircraft, electrical equipment is distributed across the wings or fuselage, resulting in a more complex spatial distribution of heat loads and placing higher demands on the thermal management system. Furthermore, the power requirements, heat loads, and environmental conditions vary significantly across different flight phases, increasing the need for a combination of thermal management and flight profile analysis.

[0004] Existing thermal management methods for aerospace hybrid propulsion systems primarily focus on preventing overheating of electrical components or meeting safe temperature limits, neglecting the significant temperature-dependent efficiency changes of these components. This leads to the motors and fuel cells operating outside their optimal temperature ranges for extended periods, resulting in decreased system efficiency. Furthermore, to meet peak operating temperature demands, traditional methods often rely on increasing heat exchanger capacity or introducing redundant cooling loops, increasing structural weight and energy consumption. Therefore, there is an urgent need for a thermal management method that can proactively maintain the operating temperature of electrical components within their efficient range across multiple flight phases while avoiding excessive cooling capacity configuration. Summary of the Invention

[0005] To address the issues of temperature sensitivity in the efficiency of electrical components such as motors and fuel cells in aviation hydrogen hybrid propulsion systems, and the significant changes in heat load during flight missions, the present invention aims to provide a low-compensation thermal management method for hydrogen hybrid propulsion systems that maintains efficient operation of electrical components. Instead of focusing solely on "preventing overheating," this method centers on controlling the efficient operating temperature range of electrical components and introduces a water storage tank as a heat energy transfer unit. This tank transfers excess heat generated during the high power demand phase of takeoff and climb, and then releases it in an orderly manner during the cruise phase, achieving peak utilization of heat between different flight phases.

[0006] The objective of this invention is achieved through the following technical solution: A low-compensation thermal management method for a hydrogen-hybrid propulsion system that maintains efficient operation of electrical components is characterized by using liquid hydrogen as a terminal heat sink, including a thermal energy storage peak utilization strategy and a thermal response flow control strategy. The thermal energy storage and peak utilization strategy introduces a water tank as a thermal energy storage unit to dynamically adjust the storage and release of heat at different stages of the flight mission. During takeoff and climb, the thermal load of electrical components is high, while the heat dissipation capacity of the terminal heat sink is limited. The heat is stored in the water tank and waits to be released gradually during the cruise phase, avoiding the need for excessive configuration of the cooling system. The thermal response flow control strategy ensures that the temperature of the electrical components remains within the high-efficiency range by precisely adjusting the heat exchange flow between the electrical components and the water storage tank. When the temperature of the electrical components is too high, the flow rate of the cooling medium is increased to transfer excess heat to the water storage tank; when the temperature is too low, the flow rate is reduced to avoid overcooling and ensure stable equipment temperature.

[0007] Furthermore, during the implementation of the thermal energy transfer and peak utilization strategy, the system divides the flight phase according to the flight mission profile and pre-sets the effective heat capacity range of the water storage tank. During takeoff and climb, the propulsion system outputs higher power, and the heat generated by the electrical components increases significantly. When the instantaneous heat dissipation capacity of the terminal heat sink is insufficient to completely dissipate the generated heat, the system maintains the normal heat exchange state between the electrical components and the intermediate cooling circuit, introduces the excess heat carried by the intermediate cooling medium into the water tank, exchanges heat with the water, and stores it in the sensible heat of the water, completing the staged heat storage process. During this stage, the water tank acts as a heat storage unit to absorb the heat that cannot be dissipated in time under peak operating conditions, preventing the temperature of the electrical components from deviating from their efficient operating temperature range. After entering the cruise phase, the system power demand decreases, the heat generation level of electrical components drops significantly, the terminal heat sink has sufficient heat dissipation capacity, and the control system gradually adjusts the heat exchange state between the water storage tank and the terminal heat sink, so that the heat stored in the water is released through the intermediate cooling circuit and discharged from the system, completing the heat release process. By sequentially scheduling heat storage and release as described above, heat can be transferred in an orderly manner between different flight phases, avoiding over-configuration of the cooling system due to short-term high heat loads.

[0008] Furthermore, the thermal response flow control strategy is used to adjust the temperature of electrical components in real time during different flight phases, thereby achieving dynamic control of the flow rate of the intermediate cooling medium; the flow rate is continuously adjusted under different operating conditions based on the internal temperature of the electrical components and the inlet temperature of the intermediate cooling medium. When the heat generated by the electrical components is approximately equal to the heat carried away by the intermediate cooling medium, the system is in thermal equilibrium, maintaining the current flow rate and keeping the temperature of the electrical components stable within the high-efficiency operating temperature range. When the heat generated by the electrical components exceeds the heat carrying capacity of the intermediate cooling medium, causing the equipment temperature to rise, the control system increases the flow rate of the intermediate cooling medium to improve the instantaneous heat dissipation capacity and transfer the excess heat to the subsequent circuit or water tank in time to suppress the temperature from continuing to rise. When the heat generated by the electrical components is less than the heat removed by the intermediate cooling medium, causing the equipment temperature to drop or even become overcooled, the control system reduces the flow rate of the intermediate cooling medium accordingly, reduces the heat dissipation intensity, and prevents the temperature of the electrical components from deviating from the efficient operating range.

[0009] At the control execution level, the thermal response flow control strategy is limited to the equipment startup phase; When the temperature gradually rises during the initial operation of the equipment, and the internal temperature of the electrical components or the inlet temperature of the intermediate cooling medium does not reach the preset activation threshold, the intermediate cooling circuit maintains a low flow rate to reduce unnecessary cooling. Once the temperature reaches the activation threshold, the pump starts and outputs the set initial flow rate, allowing the intermediate cooling circuit to gradually establish a stable heat exchange capacity. By setting the activation threshold and initial flow rate appropriately, the flow rate ramp-up process is matched with the equipment's heat generation process, thereby reducing the temperature overshoot and enabling electrical components to quickly enter and stabilize within the high-efficiency operating temperature range.

[0010] A low-compensation thermal management method for a hydrogen-hybrid propulsion system that maintains efficient operation of electrical components includes the following steps: Temperature monitoring and analysis: Continuously monitor the operating temperature of electrical components to ensure they are maintained within the optimal operating range; Real-time flow adjustment: The flow rate of the intermediate cooling medium is dynamically adjusted according to temperature changes to achieve thermal response regulation; Phased thermal energy storage and release: Excess heat is stored in a water tank during high heat load phases and then released during low heat load phases to reduce the need for excessive cooling configurations. Continuous optimization of equipment operating status: Adjust the operating mode of the thermal management system according to different stages of the flight mission to ensure that electrical components are always in a high-efficiency operating state.

[0011] This invention is based on a multi-heat sink-multi-loop thermal management system architecture for an aviation hydrogen hybrid propulsion system, using liquid hydrogen as the terminal heat sink, and formulates a thermal energy transfer management method for low-compensation thermal management of hydrogen hybrid propulsion systems to maintain the efficient operation of electrical components.

[0012] The thermal response flow control strategy not only ensures the efficiency of electrical components during operation, but also avoids energy waste due to overcooling.

[0013] The thermal energy storage and peak utilization strategy introduces a water storage tank as a thermal energy storage unit to dynamically adjust the storage and release of heat at different stages of the flight mission.

[0014] Because the electrical components operate within their efficient operating temperature range for most of the time, efficiency losses due to overcooling or overheating are avoided. This reduces the need for additional power and heat exchange capacity at the system level, achieving the goal of low-compensation thermal management. Low compensation means avoiding the need for additional heat exchange capacity or power to cope with short-term high heat loads, while still meeting the efficient operating temperature requirements of the electrical components. This reduces system weight, structural complexity, and fuel consumption.

[0015] The beneficial effects of this invention are: This invention directly targets the efficient operating temperature range of electrical components. Through the synergistic effect of thermal response flow control and heat peak-shifting strategies, it ensures that key electrical components such as motors and fuel cells operate within their efficient range throughout the entire flight mission, effectively suppressing efficiency degradation caused by temperature deviations. Compared to traditional thermal management methods that only meet safety temperature requirements, this invention reduces efficiency losses in electrical components, lowers peak heat dissipation demands, and reduces overall system energy compensation without significantly increasing heat exchange capacity or system weight. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the thermal management cooling circuit of the present invention.

[0017] Figure 2 This is a schematic diagram of a thermal response flow control strategy. Detailed Implementation

[0018] A low-compensation thermal management method for a hydrogen-hybrid propulsion system that maintains efficient operation of electrical components is proposed. Based on a multi-heat sink-multi-loop thermal management system architecture for liquid hydrogen, this method comprehensively considers the real-time heat dissipation requirements of electrical components, airborne layout, and the power and heat load characteristics that change with the flight mission profile throughout the mission. It forms a synergistic approach combining a thermal response flow control strategy and a thermal energy storage and peak-shifting utilization strategy. This method directly controls the efficient operating temperature range of the electrical components. By dynamically adjusting the flow rate of the intermediate cooling medium and introducing it into the water tank for phased heat storage and release, the method ensures that the electrical components operate stably within the efficient temperature range throughout the mission. Simultaneously, it recovers excess waste heat from the system to preheat the liquid hydrogen, improving energy utilization efficiency.

[0019] Based on the aforementioned system architecture and control objectives, the management method of this invention, in its specific implementation, uses thermal response flow control strategy and thermal energy storage peak utilization strategy as two complementary core components. These are used to achieve stable control of the operating temperature of electrical components during the flight phase and reasonable allocation of heat load between different flight phases, thereby continuously maintaining the electrical components in the high-efficiency operating temperature range. Figure 1 This is a schematic diagram of the thermal management cooling circuit of the present invention, illustrating the system architecture of the thermal energy transfer and flow control strategy, including the heat exchange path between electrical components, water storage tank and cooling circuit.

[0020] The thermal energy storage and peak utilization strategy introduces a water tank as a thermal energy storage unit to dynamically adjust the storage and release of heat at different stages of the flight mission. During takeoff and climb, the thermal load of electrical components is high, while the heat dissipation capacity of the terminal heat sink is limited. The heat is stored in the water tank and waits to be released gradually during the cruise phase, avoiding the need for excessive configuration of the cooling system. The thermal response flow control strategy ensures that the temperature of the electrical components remains within the high-efficiency range by precisely adjusting the heat exchange flow between the electrical components and the water storage tank. When the temperature of the electrical components is too high, the flow rate of the cooling medium is increased to transfer excess heat to the water storage tank; when the temperature is too low, the flow rate is reduced to avoid overcooling and ensure stable equipment temperature.

[0021] During the implementation of the thermal energy transfer and peak utilization strategy, the system divides the flight phase according to the flight mission profile and pre-sets the effective heat capacity range of the water storage tank.

[0022] During takeoff and climb, the propulsion system outputs higher power, leading to a significant increase in heat generation from electrical components. When the immediate heat dissipation capacity of the terminal heat sink is insufficient to completely dissipate the generated heat, the system does not compensate by increasing the terminal heat exchange capacity or adding cooling loops. Instead, it maintains normal heat exchange between the electrical components and the intermediate cooling loop, introducing excess heat carried by the intermediate cooling medium into the water storage tank. This heat exchange occurs with the water and is stored in the sensible heat of the water, completing a phased heat storage process. During this phase, the water storage tank acts as a temporary heat storage unit, absorbing heat that cannot be dissipated in time under peak operating conditions, thereby preventing the temperature of the electrical components from deviating from their efficient operating temperature range.

[0023] Once the cruise phase begins, system power demands decrease, heat generation from electrical components drops significantly, and the terminal heat sink has sufficient heat dissipation capacity. The control system gradually adjusts the heat exchange state between the water tank and the terminal heat sink, allowing the heat stored in the water to be released through the intermediate cooling loop and discharged from the system, completing the heat release process. Through the sequential scheduling of heat storage and release described above, orderly heat transfer between different flight phases is achieved, avoiding over-configuration of the cooling system due to short-term high heat loads.

[0024] Figure 2 This is a schematic diagram of a thermal response flow control strategy. It details how heat is transferred by adjusting the flow rate of the cooling medium when the temperature of an electrical component exceeds its high-efficiency range, ensuring that the component operates within its high-efficiency range.

[0025] The thermal response flow control strategy is used to adjust the temperature of electrical components in real time during different flight phases. Its core lies in the dynamic control of the intercooler flow rate. This strategy uses the internal temperature of the electrical components and the inlet temperature of the intercooler as control criteria to continuously adjust the flow rate under different operating conditions. When the heat generated by the electrical components is approximately equal to the heat removed by the intercooler, the system is in thermal equilibrium, maintaining the current flow rate to keep the electrical component temperature stable within the high-efficiency operating temperature range. When the heat generated by the electrical components exceeds the heat-carrying capacity of the intercooler, causing the equipment temperature to rise, the control system increases the intercooler flow rate to improve instantaneous heat dissipation capacity, transferring excess heat to subsequent circuits or the water tank in a timely manner to suppress further temperature increases. When the heat generated by the electrical components is less than the heat removed by the intercooler, causing the equipment temperature to drop or even become overcooled, the control system correspondingly reduces the intercooler flow rate to decrease heat dissipation intensity and prevent the electrical component temperature from deviating from the high-efficiency operating range.

[0026] At the control execution level, the thermal response flow control strategy further limits the operation during the equipment startup phase. When the temperature gradually rises during the initial operation of the equipment, and the internal temperature of the electrical components or the inlet temperature of the intermediate cooling medium has not reached the preset activation threshold, the intermediate cooling circuit maintains a low flow rate to reduce unnecessary cooling.

[0027] Once the temperature reaches the activation threshold, the pump starts and outputs the set initial flow rate, allowing the intermediate cooling circuit to gradually establish a stable heat exchange capacity. Given that there is some heat accumulation inside the equipment during the startup phase, the temperature may continue to rise for a short period. By appropriately setting the activation threshold and initial flow rate, the flow rate ramp-up process is matched with the equipment's heat generation process, thereby reducing temperature overshoot and enabling the electrical components to quickly enter and stabilize within their efficient operating temperature range.

[0028] The specific steps of the low-compensation thermal management method for a hydrogen-hybrid propulsion system that maintains efficient operation of electrical components according to the present invention are as follows: Temperature monitoring and analysis: Continuously monitor the operating temperature of electrical components to ensure they are maintained within the optimal operating range; Real-time flow adjustment: The flow rate of the intermediate cooling medium is dynamically adjusted according to temperature changes to achieve thermal response regulation; Phased thermal energy storage and release: Excess heat is stored in a water tank during high heat load phases and then released during low heat load phases to reduce the need for excessive cooling configurations. Continuous optimization of equipment operating status: Adjust the operating mode of the thermal management system according to different stages of the flight mission to ensure that electrical components are always in a high-efficiency operating state.

[0029] The strategy of peak utilization of thermal energy storage is applied to the cooling circuit of fuel cells. Fuel cells have high heat dissipation requirements, and the cooling capacity of the terminal heat sink is more easily limited during takeoff and climb. By scheduling heat storage and heat release in stages, the fuel cell can be more effectively ensured to always operate within the target temperature range.

[0030] This invention reduces efficiency losses in electrical components, lowers peak heat dissipation requirements, and reduces overall system energy compensation without significantly increasing heat exchange capacity or system weight. Simulation results show that, under the same flight mission conditions, the hydrogen-hybrid propulsion system using this invention exhibits significantly reduced fuel consumption and improved overall system energy utilization efficiency. See Table 1: Table 1

[0031] In summary, the low-compensation thermal management method for hydrogen hybrid propulsion systems that maintains efficient operation of electrical components in this invention addresses the phased changes in heat dissipation and power requirements of electrical components under flight mission profiles. It rationally allocates multiple heat sinks and coordinates thermal response flow control and peak utilization strategies for thermal energy storage to achieve stable maintenance of electrical component temperatures within the high-efficiency range. Simultaneously, it recovers and utilizes system waste heat to preheat liquid hydrogen, thereby improving system energy utilization efficiency and reducing energy compensation without increasing overcooling capacity. This solves the problems of complex spatial distribution of electrical components, high thermal management requirements, and reduced efficiency of electrical components in aviation hydrogen hybrid propulsion systems.

Claims

1. A method for low-compensated thermal management of a hydrogen hybrid propulsion system that maintains the efficient operation of electrical components, characterized in that, The liquid hydrogen is used as a terminal heat sink, including a thermal energy dump peak-shaving strategy and a thermal response flow control strategy; The thermal energy dump peak-shaving strategy introduces a water storage tank as a thermal energy dump unit to dynamically adjust the storage and release of heat at different stages of the flight mission. During the take-off and climbing stages, the thermal load of the electrical components is high, and the heat is stored in the water tank due to the limited heat dissipation capacity of the terminal heat sink. The heat is gradually released during the cruising stage to avoid the need for excessive cooling system configuration. The thermal response flow control strategy precisely adjusts the heat exchange flow between the electrical components and the water storage tank to ensure that the temperature of the electrical components is always within the high-efficiency interval. When the temperature of the electrical components is too high, the flow of the cooling working medium is increased to transfer the excess heat to the water storage tank. When the temperature is too low, the flow is reduced to avoid overcooling and ensure the stability of the equipment temperature.

2. The method of claim 1, wherein the hydrogen hybrid propulsion system low- accommodation thermal management method maintains the high efficiency of the electrical components, and During the implementation of the thermal energy dump peak-shaving strategy, the system divides the flight stages according to the flight mission profile and pre-sets the effective heat capacity range of the water storage tank. During the take-off and climbing stages, the output power of the propulsion system is high, and the heat generated by the electrical components increases significantly. When the instantaneous heat dissipation capacity of the terminal heat sink is insufficient to completely remove the generated heat, the system maintains the normal heat exchange state between the electrical components and the intermediate cooling circuit, and the excess heat carried by the intermediate cooling working medium is introduced into the water storage tank to exchange heat with the water and store it in the sensible heat of the water, completing the phase heat storage process. The water storage tank acts as a temporary heat storage unit during this stage to absorb the heat that cannot be timely removed under peak conditions, preventing the temperature of the electrical components from deviating from its high-efficiency operating temperature interval. After entering the cruising stage, the system power demand decreases, and the heat generation level of the electrical components decreases significantly. The terminal heat sink has sufficient heat dissipation capacity, and the control system gradually adjusts the heat exchange state between the water storage tank and the terminal heat sink to release the heat stored in the water body through the intermediate cooling circuit and remove it from the system, completing the heat release process. Through the above sequential scheduling of heat storage and heat release, the orderly transfer of heat between different flight stages is achieved, avoiding the need for excessive cooling system configuration due to short-term high thermal load.

3. The method of claim 2, wherein the hydrogen hybrid propulsion system low- accommodation thermal management method maintains the high efficiency of the electrical components, and wherein the hydrogen hybrid propulsion system low- accommodation thermal management method is characterized by, The thermal response flow control strategy is used to adjust the temperature of the electrical components in real time during different flight stages, and to dynamically control the flow of the intermediate cooling working medium. The internal temperature of the electrical components and the inlet temperature of the intermediate cooling working medium are used as control bases to continuously adjust the flow under different operating conditions. When the heat generated by the electrical components is equal to the heat carried away by the intermediate cooling working medium, the system is in a state of thermal equilibrium, maintaining the current flow unchanged to stabilize the temperature of the electrical components within the high-efficiency operating temperature interval. When the heat generated by the electrical components is greater than the heat carrying capacity of the intermediate cooling working medium, causing the equipment temperature to rise, the control system increases the flow of the intermediate cooling working medium to increase the instantaneous heat dissipation capacity and timely transfer the excess heat to the subsequent circuit or the water storage tank to prevent the temperature from continuing to rise. When the heat generated by the electrical components is less than the heat carried away by the intermediate cooling working medium, causing the equipment temperature to drop or even appear overcooling trend, the control system correspondingly reduces the flow of the intermediate cooling working medium to reduce the heat dissipation intensity and avoid the temperature of the electrical components deviating from the high-efficiency operating interval.

4. The method of claim 3, wherein the hydrogen hybrid propulsion system low- accommodation thermal management method maintains the high efficiency of the electrical components, and At the control execution level, the thermal response flow control strategy is limited to the equipment start-up stage. When the device's initial temperature gradually increases, and the internal temperature of the electrical components or the inlet temperature of the intermediate cooling working medium does not reach the preset activation threshold, the intermediate cooling circuit maintains a lower flow rate to reduce unnecessary cooling. When the temperature reaches the activation threshold, the pump starts and outputs a set initial flow rate, allowing the intermediate cooling circuit to gradually establish stable heat exchange capacity. By reasonably setting the activation threshold and initial flow rate, the flow rate climbing process is matched with the device's heat production process, thereby reducing the temperature overshoot amplitude and allowing the electrical components to enter and stabilize in the high-efficiency working temperature range as soon as possible.

5. The method of claim 1, wherein the hydrogen hybrid propulsion system low- accommodation thermal management method maintains the high efficiency of the electrical components, and wherein the hydrogen hybrid propulsion system low- accommodation thermal management method is characterized by, The method includes the following steps: Temperature monitoring and analysis: continuously monitor the operating temperature of the electrical components to ensure they remain within the optimal working range; Real-time flow adjustment: dynamically adjust the flow rate of the intermediate cooling working medium based on temperature changes to achieve thermal response regulation; Phase heat energy storage and release: use the water storage tank to store excess heat during high heat load stages and release it during low heat load stages to reduce the need for excessive cooling configurations; Continuous optimization of device working state: adjust the working mode of the thermal management system according to different stages of the flight mission to ensure that the electrical components are always in an efficient working state.

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