Energy Generation and Management System for a Hydrogen Hybrid Aircraft with Combined Heat, Power and Hydrogen Energy

Abstract

The present invention discloses an energy generation and management system for a hydrogen energy hybrid aircraft with power, heat, and electricity coupling, comprising: an air supply system, an aviation kerosene supply system, a water supply system, an electrical system, a reformer, a fuel cell, and a combustion chamber; an air intake in the air supply system is connected to a compressor, and after passing through a heat exchanger, it is connected to the fuel cell and the combustion chamber; an oil pump in the aviation kerosene supply system is connected to the combustion chamber and the reformer after passing through a heat exchanger; a water pump in the water supply system is connected to the reformer through a heat exchanger; the anode of the fuel cell is connected to the reformer, and the cathode is connected to the heat exchanger; the combustion chamber is connected to the fuel cell and is connected to a turbine and a generator through the reformer; both the generator and the fuel cell are connected to the electrical system. The present invention realizes precise regulation of system energy generation and management through power distribution and coupled calculations of the heat and mass system and electrical characteristics, and efficient collaborative management of flow rate, thermal energy, power, and electrical energy.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft energy generation and management, and particularly relates to an energy generation and management system for a hydrogen energy hybrid aircraft with work-thermal-electric coupling. Background Art

[0002] With the development of aircraft electrification and the progress of electronic device integration technology, the electrical power demand of aircraft has increased exponentially. Currently, electrical energy on aircraft is mainly obtained in two ways: one is to generate electricity by driving a generator with an engine, and the other is to supply power using a power battery. The former has low power generation efficiency and increases the load on the engine, while the latter is limited by the energy density of the power battery and is difficult to meet the high energy requirements of aviation applications. Therefore, developing an aviation power generation system with high efficiency and high energy density has become an urgent problem to be solved.

[0003] As an energy conversion device that directly converts chemical energy into electrical energy, hydrogen fuel cells have the advantages of high efficiency and low emissions, and are considered the fourth-generation power generation technology after thermal power, hydropower, and nuclear power. Among them, solid oxide fuel cells (SOFCs) have received extensive attention due to their high operating temperature (700°C - 1000°C), fuel flexibility, and high power generation efficiency. In addition, gas turbines (GTs) have the characteristics of high power density and fast response, and are one of the main forms of aircraft engines. By adopting an SOFC-GT hybrid system and using the high-temperature exhaust gas of the SOFC to drive the GT to work, the cascaded utilization of energy is realized, which has significant efficiency advantages.

[0004] Currently, the research on SOFC-GT hybrid systems mainly focuses on improving power output and system efficiency, emphasizing improving the performance of components such as SOFCs and GTs, and optimizing the energy generation system architecture to enhance the overall performance of the system. Traditional aircraft energy management systems usually design the power system (power transmission, transformation, and distribution) and the hybrid energy generation system separately, resulting in the power system being unable to fully utilize the energy generated by the hybrid energy generation system, or the hybrid energy generation system being unable to meet the requirements of the power system, lacking comprehensive coordination of energy generation and management, resulting in low energy utilization efficiency and high system complexity, and unable to achieve global optimization management of the system. Summary of the Invention

[0005] The main object of the present invention is to provide an energy generation and management system for a hydrogen energy hybrid aircraft with work-thermal-electric coupling. Through the coupling calculation of power distribution, heat and mass systems, and electrical characteristics, and the efficient coordinated management of flow rate, thermal energy, power, and electrical energy, precise control of the generation and management of system energy is achieved.

[0006] The object of the present invention is achieved through the following technical solutions:

[0007] A power-thermoelectric-coupled hydrogen hybrid aircraft energy generation and management system, characterized by comprising: an air supply system, an aviation kerosene supply system, a water supply system, an electric power system, a reformer, a fuel cell, and a combustion chamber; the intake duct in the air supply system is connected to a compressor, and after passing through an air-high temperature exhaust gas heat exchanger, it is connected to the fuel cell and the combustion chamber; the oil pump in the aviation kerosene supply system is connected to the combustion chamber and the reformer after passing through an aviation kerosene-high temperature exhaust gas heat exchanger; the water pump in the water supply system is connected to the reformer through a water-high temperature exhaust gas heat exchanger; the fuel cell is connected to the reformer and the air-high temperature exhaust gas heat exchanger; the combustion chamber is connected to the fuel cell and is connected to a turbine and a generator through the reformer; both the generator and the fuel cell are connected to the electric power system.

[0008] Further, the 230V AC main busbar in the electric power system is connected to the generator. One part directly supplies the 230V AC load, and the other part converts the 230V alternating current into 115V alternating current through an AC-AC converter and is connected to the 115V AC busbar; the first DC-DC converter is connected to the fuel cell. One part supplies the 270V DC main busbar, one part supplies the 270V DC load, one part is connected to the 28V DC busbar through the second DC-DC converter to supply the 28V DC load, and the other part is connected to the 115V AC busbar to provide stable electric energy for the 115V AC load, as well as the water pump and the oil pump.

[0009] Further, in the air supply system, the intake duct is the air input end of the system, which inhales air from the outside. After being compressed by the compressor, it enters the air-high temperature exhaust gas heat exchanger through a pipeline. The air passing through the heat exchanger enters the cathode of the fuel cell and the combustion chamber respectively to provide the oxygen required for the reaction.

[0010] In the aviation kerosene supply system, the oil pump diverts the aviation kerosene to the combustion chamber and the reformer to ensure that the flow rate and pressure of the aviation kerosene meet the combustion and reforming requirements.

[0011] In the water supply system, the water pump is responsible for preheating the water through the water-high temperature exhaust gas heat exchanger and supplying it to the reformer. The water-carbon ratio is set at 3:1 to ensure the progress of the reforming reaction.

[0012] The reformer adopts the steam reforming process to convert aviation kerosene into a multi-component mixed gas rich in hydrogen and carbon monoxide for use by the SOFC.

[0013] As the core component of a hybrid power system, in a solid oxide fuel cell (SOFC), the cathode receives the input from air, and the anode receives the input of a mixed gas (mainly composed of hydrogen and carbon monoxide) from the reformer outlet. An electrochemical reaction occurs to generate electric power. The combustion chamber further burns the high-temperature exhaust gas generated by the SOFC and aviation kerosene to produce high-temperature and high-pressure exhaust gas, which drives the turbine to expand and do work, and then drives the generator to generate electricity. The output current of the generator is incorporated into the system to provide additional power support for the system.

[0014] In the present invention, by adjusting the value of the load in the power system, the electric power demand under different flight conditions can be simulated. The change in the electric power load affects the power demand of the power system, which is then fed back to the hybrid power system, causing dynamic adjustments to the output power, working fluid flow rate, heat transfer, and power demand of the pump in the SOFC-GT hybrid power system. Furthermore, the dynamic change in the electric power demand of the auxiliary components is transmitted to the total load demand. Through such cyclic iteration, the system continuously adjusts itself until the initial electric power load demand is met, and finally the system stability is achieved.

[0015] The present invention has the following beneficial effects:

[0016] In the present invention, through the coupled calculation of multiple physical fields of work-heat-electricity, the efficient integrated management of power, thermal energy, and electric energy is achieved. According to the changing power demands of the aircraft at different flight stages, the SOFC-GT hybrid power system can automatically adjust its operating parameters according to the change in electric power demand, adapt to different flight conditions, ensure the matching of energy supply and demand, reduce energy waste, and the closed-loop feedback mechanism enables the system to quickly respond to changes and maintain stable operation. Description of the Drawings

[0017] Figure 1 It is a structural block diagram of an energy generation and management system for a hydrogen energy hybrid aircraft with work-heat-electricity coupling.

[0018] Markings in the figure: 1 - air intake, 2 - compressor, 3 - air-high temperature exhaust gas heat exchanger, 4 - fuel cell, 5 - combustion chamber, 6 - reformer, 7 - turbine, 8 - aviation kerosene-high temperature exhaust gas heat exchanger, 9 - water-high temperature exhaust gas heat exchanger, 10 - oil pump, 11 - water pump, 12 - generator, 13 - first DC-DC converter, 14 - 230V AC main busbar, 15 - 230V AC load, 16 - AC-AC converter, 17 - 270V DC main busbar, 18 - second DC-DC converter, 19 - 28V DC busbar, 20 - 28V DC load, 21 - 270V DC load, 22 - DC-AC converter, 23 - 115V AC busbar, 24 - 115V AC load. Detailed Embodiments

[0019] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following detailed description of the specific embodiments of the present invention will be given in conjunction with the accompanying drawings. The specific operating steps of the method are as follows:

[0020] As Figure 1 shown, an energy generation and management system for a power-thermal-electricity coupled hydrogen energy hybrid aircraft. The system realizes the precise regulation of the generation and management of system energy through the coupling calculation of power distribution, heat and mass systems, and electrical characteristics, and the efficient collaborative management of flow, heat energy, power, and electrical energy. It mainly consists of an electrical system and an SOFC-GT hybrid system, where the SOFC-GT hybrid system can be specifically divided into an air supply system, an aviation kerosene supply system, and a water supply system.

[0021] Among them: In the air supply system, the intake duct 1 is the air input end of the system, which sucks in air from the outside. After being compressed by the compressor 2, it enters the air-high temperature exhaust gas heat exchanger 3 through a pipeline. The air passing through the heat exchanger enters the cathode of the fuel cell 4 and the combustion chamber 5 respectively, providing the oxygen required for the reaction.

[0022] In the aviation kerosene supply system, the oil pump 10 diverts the aviation kerosene to the combustion chamber 5 and the reformer 6 to ensure that the flow rate and pressure of the aviation kerosene meet the combustion and reforming requirements. After the combustion chamber 5 burns the fuel cell exhaust gas and aviation kerosene, high-temperature and high-pressure exhaust gas is generated. First, the exhaust gas passes through the reformer 6 to provide the necessary heat for the steam reforming reaction to promote the generation of hydrogen. Subsequently, the exhaust gas passes through three heat exchangers: the aviation kerosene-high temperature exhaust gas heat exchanger 8, the water-high temperature exhaust gas heat exchanger 9, and the air-high temperature exhaust gas heat exchanger 3 in sequence; the aviation kerosene-high temperature exhaust gas heat exchanger 8 is used to preheat the aviation kerosene entering the reformer, improve the evaporation efficiency of the fuel, and reduce the starting temperature of the reformer; the water-high temperature exhaust gas heat exchanger 9 is used to preheat the water entering the reformer to ensure that the water rises to a certain temperature before entering the reformer, improving the reforming reaction rate; the air-high temperature exhaust gas heat exchanger 3 is used to preheat the air entering the fuel cell and the combustion chamber, increasing the temperature of the oxygen supply.

[0023] In the water supply system, the water pump 11 is responsible for preheating the water through the water-high temperature exhaust gas heat exchanger 9 and supplying it to the reformer 6, with the water-carbon ratio set at 3:1. Under high-load operation or low-load conditions of the system, due to different hydrogen demands, the demands for aviation kerosene and water in the reforming reaction change. By controlling the power of the water pump 11 and the oil pump 10, the rotation speeds of the water pump 11 and the oil pump 10 are adjusted, and at the same time, the flow rates of water and aviation kerosene are increased or decreased. During the adjustment process, the water-carbon ratio of the reforming reaction is always maintained at 3:1 to ensure the progress of the reforming reaction.

[0024] The reformer 6 adopts the steam reforming process to convert aviation kerosene into a multi-component mixed gas rich in hydrogen and carbon monoxide for use by the SOFC 4.

[0025] As the core component of the hybrid power system, the cathode of the SOFC 4 receives the input from the air, and the anode receives the input of the mixed gas (mainly composed of hydrogen and carbon monoxide) from the reformer outlet to carry out an electrochemical reaction to generate electric energy. The combustion chamber 5 further combusts the high-temperature exhaust gas generated by the SOFC and the aviation kerosene to generate high-temperature and high-pressure tail gas, which drives the turbine 7 to expand and do work, and then drives the generator to generate electricity. The turbine 7 expands and does work by using the high-temperature and high-pressure tail gas, which is converted into mechanical energy and is mainly used to drive the generator 12 to generate electricity for the power system; at the same time, the turbine 7 also drives the compressor 2 to operate through mechanical connection to compress the air entering the air supply system to ensure the oxygen supply required by the fuel cell 4 and the combustion chamber 5. The output current of the generator is incorporated into the system to provide additional power support for the system. The compressor 2 and the generator 12 are driven by the turbine 7 to operate, and the compressor 2, the generator 12 and the turbine 7 are of a coaxial structure (represented by a thick black line in the figure), forming an integrated structure of turbine-compressor-generator. The turbine 7 not only drives the compressor 2 to compress the air, but also drives the generator 12 to generate electricity at the same time, ensuring the coordination between the air supply and the electricity generation, and improving the overall mechanical efficiency and compactness.

[0026] The loads in the power system are connected to different busbars to utilize the electric energy generated in the SOFC-GT hybrid power system. Each load is connected to the corresponding voltage level to ensure stable power supply. The electric energy generated by the turbogenerator is connected to the 230V AC main busbar 14. A part of it is directly supplied to the 230V AC load 15, and the other part converts the 230V alternating current into 115V alternating current through the AC-AC converter 16 and is connected to the 115V AC busbar 23 to supply various electrical equipment. The electric energy generated by the fuel cell in the system is supplied to the 270V DC main busbar 17 through the first DC-DC converter 13. A part of it meets the demand of the 270V DC load 21, a part is connected to the 28V DC busbar 19 through the second DC-DC converter 18 to supply the 28V DC load 20, and the other part is connected to the 115V AC busbar 23 through the DC-AC converter 22 to provide stable electric energy for the 115V AC load 24 and the water pump and oil pump.

[0027] During the takeoff phase of the aircraft, the power demand is high. By increasing the value of the 230V AC load 15 in the power system, a high power demand is simulated. After the power system detects the increased load, it feeds back the demand information to the SOFC 4 and the generator 12 in the hybrid power system. The hybrid power system then makes adjustments. By adjusting the values of different types of loads in the power system, the electric power demands of the aircraft under different flight conditions are simulated, and the dynamic adjustment of the output power, working fluid flow rate, heat transfer, and pump power demand of the fuel cell 4 and the generator 12 is achieved to match the electric power demand. The system continuously monitors the difference between the actual output electric power and the demanded electric power, and performs closed-loop control to ensure the stability of the power supply and the efficient operation of the system.

[0028] The control system adjusts the output of the oil pump 10 to increase the supply of aviation kerosene to the reformer 6 and increase the production of hydrogen-rich fuel. At the same time, the operation of the water pump 11 is adjusted to ensure that the steam supply meets the requirements of the reforming reaction. In addition, the operating parameters of the compressor 2 are adjusted to change the air flow rate and supply it to the SOFC cathode. On the one hand, it meets the electrochemical reactions inside the SOFC, and on the other hand, the excess air can ensure that the SOFC maintains a constant operating temperature and guarantees a stable output of electric energy.

[0029] In the combustion chamber 5, the supply of aviation kerosene is increased to intensify the combustion process and generate more high-temperature and high-pressure gas. The operating parameters of the turbine 7 are adjusted to increase the mechanical work output and drive the generator to generate more alternating current.

[0030] With the increase in the supply of fuel and air, the working fluid flow rate (aviation kerosene, air, water, etc.) in the system also increases accordingly. The working loads of the oil pump 10, the water pump 11, and the compressor 2 increase, and their mechanical power and electric power demands also increase. The power system needs to provide additional electric energy support for these auxiliary devices.

[0031] The new electric power demand is further adjusted. After multiple cycle iterations, the system gradually reaches a new equilibrium state. At this time, the output powers of the SOFC and the GT meet the high power demands during the takeoff phase, the working fluid flow rate and the heat transfer process are stable, and the power demand of the pump matches the power supply capacity of the power system. The system achieves stable operation and meets the initially set electric power demand.

[0032] Through the coordinated operation of the air supply system, aviation kerosene supply system, and water supply system, the present invention ensures the stable operation of the reformer, fuel cell, and combustion chamber. The electric energy generated by the fuel cell and turbine generator is distributed to each power busbar of the system as needed through different converters, ensuring stable power supply for each component of the aircraft. By adjusting the load in the power system, the electric power demand under different flight conditions can be simulated. The change in the electric power load affects the power demand of the power system, which is fed back to the SOFC-GT hybrid power system, causing dynamic adjustments to the output power, working fluid flow rate, heat transfer, and power demand of the pump of the SOFC and GT, resulting in changes in the electric power demand of the auxiliary components and further affecting the total load of the power system. Through such cyclic iteration, the system continuously self-adjusts until the initially set load demand is met, ultimately achieving the stable operation of the system and forming an adaptive closed-loop control mechanism. Throughout the process, the system realizes precise regulation of energy generation and management through the power-heat-electricity coupling calculation and coordinated management of the power system and the SOFC-GT hybrid power system.

[0033] The above description is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be regarded as the protection scope of the present invention.

Claims

1. A power-thermal-electric coupled hydrogen hybrid aircraft energy generation and management system, characterized in that: include: An air supply system, an aviation kerosene supply system, a water supply system, an electric power system, a reformer, a fuel cell and a combustion chamber; the air inlet (1) in the air supply system is connected to the compressor (2), and is connected to the fuel cell (4) and the combustion chamber (5) through an air-high temperature exhaust gas heat exchanger (3); the oil pump (10) in the aviation kerosene supply system is connected to the combustion chamber (5) and the reformer (6) through an aviation kerosene-high temperature exhaust gas heat exchanger (8); the water pump (11) in the water supply system is connected to the reformer (6) through a water-high temperature exhaust gas heat exchanger (9); the fuel cell (4) is connected to the reformer (6) and the air-high temperature exhaust gas heat exchanger (3); the combustion chamber (5) is connected to the fuel cell (4), and is connected to the turbine (7) and the generator (12) through the reformer (6); the generator (12) and the fuel cell (4) are both connected to the electric power system; A 230V AC main bus (14) in the power system is connected to a generator (12), a part of which is directly supplied to a 230V AC load (15), and another part of which is converted into 115V AC power through an AC-AC converter (16) and connected to a 115V AC bus (23); a first DC-DC converter (13) is connected to a fuel cell (4), a part of which is supplied to a 270V DC main bus (17), a part of which is supplied to a 270V DC load (21), a part of which is connected to a 28V DC bus (19) through a second DC-DC converter (18) and supplied to a 28V DC load (20), and another part of which is connected to a 115V AC bus (23) through a DC-AC converter (22) to provide stable electric energy for a 115V AC load (24) and a water pump and an oil pump; The high-temperature and high-pressure exhaust gas at the outlet of the combustion chamber (5) first passes through a reformer (6) to supply the heat required for the reforming reaction, and the high-temperature exhaust gas is heat-recovered by using an aviation kerosene-high-temperature exhaust gas heat exchanger (8), a water-high-temperature exhaust gas heat exchanger (9) and an air-high-temperature exhaust gas heat exchanger (3) to preheat the aviation kerosene, water and air entering the reformer (6) and the fuel cell (4).

2. The power-thermal-electric coupled hydrogen hybrid aircraft energy generation and management system according to claim 1, characterized in that: The water-to-carbon ratio of the steam reforming reaction in the reformer (6) is 3:1, and the material ratio of the reforming reaction is adjusted by controlling the flow rates of the water pump (11) and the oil pump (10).

3. The power-thermal-electric coupled hydrogen hybrid aircraft energy generation and management system according to claim 1, characterized in that: The compressor (2), the generator (12) and the turbine (7) are coaxial structures, and the mechanical energy generated by the expansion work of the turbine (7) drives the generator (12) and drives the compressor (2) to operate at the same time.

4. The power-thermal-electric coupled hydrogen hybrid aircraft energy generation and management system according to claim 1, characterized in that: The load value in the power supply system is adjusted to simulate the power demand under different flight conditions, and the output power, working fluid flow, heat transfer and pump power demand of the fuel cell (4) and the turbine generator (12) are dynamically adjusted. The power demand is met through cyclic iteration to achieve stable operation.

5. The power-thermal-electric coupled hydrogen hybrid aircraft energy generation and management system according to claim 1, characterized in that: The amount of aviation kerosene supplied to the combustion chamber (5) is dynamically adjusted according to the power demand, the output power of the turbine (7) is optimized, and the energy balance of the system is met.

6. The power-thermal-electric coupled hydrogen-power hybrid aircraft energy generation and management system according to claim 1, characterized in that: The compressor (2) and the generator (12) are driven by the turbine (7) to form a turbine-compressor-generator integrated structure.

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