A turbo-electric power system with flywheel energy storage and methods of use

Abstract

The application provides a turbo-electric power system with a flywheel energy storage and a use method thereof, and belongs to the field of power systems of aerial vehicles; the turbo-electric power system comprises a power supply module composed of a turbo-electric machine set, a flywheel energy storage system and a battery system, the power supply module is controlled by an energy management system, power distribution of the turbo-electric machine set, the flywheel energy storage system and the battery system is coordinated through flight conditions, and after the distribution, the electric energy is distributed to an electrical load through an electrical bus. The turbo-electric machine set, the flywheel energy storage system and the battery system work coordinately through the energy management system, the risk of over-speed of a turbo-shaft engine caused by a control response difference during load unloading is inhibited, the battery avoids excessive load bearing of load fluctuation of the power system, the service time of the battery is prolonged, and the economy and safety of the aerial vehicle are improved.

Description

Technical Field

[0001] This invention belongs to the field of aircraft propulsion systems, specifically relating to a turbine electric power system with flywheel energy storage and its usage method. Background Technology

[0002] Although civil aviation accounts for only 2% of global energy-related carbon emissions annually, decarbonizing civil aviation is more difficult than other modes of transportation, leading to a faster growth rate of carbon emissions compared to road, rail, and sea transport in recent decades. With the rise of the global low-carbon and energy-saving trend, curbing the growth trend of carbon emissions in the civil aviation industry has become a focus of attention in recent years, with technological initiatives to promote system electrification being among the proposed development paths. Turbine-electric propulsion systems, as one of the important solutions for propulsion system electrification, solve the bottleneck problems brought about by battery technology development while balancing technological maturity with safety and airworthiness costs, thus possessing good market application prospects.

[0003] The turbine-electric propulsion system consists of a traditional aero-gas turbine and electrical equipment such as batteries, generators, and electric motors. Utilizing the aero-gas turbine generator set in conjunction with the battery for power supply effectively reduces fuel consumption and improves system efficiency. However, a significant difference in control response exists between the aero-gas turbine and electrical equipment in the turbine-electric propulsion system. In scenarios where demand power rapidly decreases, the aero-gas turbine exhibits excess shaft power, which is converted into shaft kinetic energy, leading to a risk of over-rotation of the aero-gas turbine shaft. Using batteries to quickly compensate for / absorb the power shortfall / excess power of the aero-gas turbine is considered an effective solution. However, when using batteries to cope with continuous fluctuations in the power output of the propulsion system, the high-frequency switching between charging and discharging states significantly reduces battery life. Furthermore, the lifespan of batteries differs by orders of magnitude from other equipment in the system. Using battery-controlled solutions further compresses the battery's on-wing time, severely impacting the operation and airworthiness of the propulsion system. Summary of the Invention

[0004] The technical problem to be solved:

[0005] To overcome the shortcomings of existing technologies, this invention provides a turbine electric propulsion system with flywheel energy storage and its usage method. By combining a flywheel structure with a traditional turbine electric propulsion system, and altering the mechanical operating structure, the rotational inertia of the engine shaft is increased, eliminating the risk of low-pressure shaft over-rotation during the transition from high-level to low-level operation. Simultaneously, utilizing the energy storage function of the flywheel structure optimizes the aircraft's energy management strategy during power fluctuations, reducing battery scheduling frequency, extending battery service life, and lowering the operating costs of the turbine electric propulsion system. This invention solves the problems of short battery service life in traditional turbine electric propulsion systems and the low-pressure shaft over-rotation problem of the turbine engine caused by differences in control response during large fluctuations in electrical load.

[0006] The technical solution of the present invention is: a turbine electric power system with flywheel energy storage, comprising a power supply module consisting of a turbine motor unit, a flywheel energy storage system, and a battery system. The power supply module is controlled by an energy management system, which coordinates the power distribution of the turbine motor unit, the flywheel energy storage system, and the battery system according to the flight conditions. After distribution, the power is distributed to the electrical load through the electrical bus.

[0007] The turbine generator set includes a turbine shaft engine, a second clutch, and a generator connected in sequence along the axial direction; one end of the low-pressure shaft of the turbine shaft engine is connected to the generator through the second clutch, and the electrical energy output by the generator is converted into direct current by a rectifier.

[0008] The flywheel energy storage system includes a bidirectional permanent magnet motor and an improved flywheel structure placed in a vacuum chamber; the bidirectional permanent magnet motor is connected to the electrical bus via a bidirectional AC / DC rectifier, and the improved flywheel structure is coaxially mounted on its output shaft, while the output shaft is connected to the other end of the low-pressure shaft of the turbine engine via a first clutch.

[0009] The battery system is connected to the electrical bus via a converter;

[0010] The electrical busbar isolates the generator busbar from the consumer busbar through the power distribution unit. The generator busbar receives electrical energy from the turbine generator set, battery system and flywheel energy storage system, and transmits it to the consumer busbar via cable before distributing it to the electrical load.

[0011] A further technical solution of the present invention is: the improved flywheel structure is a centrally hollowed-out disc with mass concentrated on the outer edge, and its moment of inertia satisfies:

[0012]

[0013] Where I is the moment of inertia, m is the overall mass of the improved flywheel structure, R1 is the inner diameter of the outer edge of the improved flywheel structure, and R2 is the outer diameter of the improved flywheel structure.

[0014] A further technical solution of the present invention is: the battery system is a fuel cell, connected to a hydrogen storage tank and connected to an electrical bus via a unidirectional converter; the unidirectional converter is a unidirectional DC / DC converter or a unidirectional DC / AC inverter;

[0015] It may be a lithium battery, connected to the electrical bus via a bidirectional converter; the bidirectional converter is a bidirectional DC / DC converter or a bidirectional DC / AC inverter.

[0016] A further technical solution of the present invention is as follows: the electrical bus is a DC electrical bus, the battery system is connected to the DC electrical bus through a DC / DC converter, the flywheel energy storage system is connected to the DC electrical bus through an AC / DC rectifier, the turbine motor unit is connected to the DC electrical bus through an AC / DC rectifier, and the electrical load is connected to the DC electrical bus through a DC / AC inverter, a DC / AC inverter, and a DC / DC converter.

[0017] A further technical solution of the present invention is as follows: the electrical load includes a high-voltage AC load, a medium-voltage AC load and a low-voltage DC load. The high-voltage AC load is connected to the electrical bus through a DC / AC inverter or an AC / AC converter. The medium-voltage AC load is connected to the electrical bus through a DC / AC inverter or an AC / AC converter. The low-voltage DC load is connected to the electrical bus through a DC / DC converter or an AC / DC rectifier.

[0018] A further technical solution of the present invention is that both the first clutch and the second clutch have engagement / disengagement functions, and the clutch status is adjusted in real time according to the turbine shaft engine speed, flywheel speed and electrical load power requirements.

[0019] A further technical solution of the present invention is: the energy management system performs dynamic power allocation, prioritizes the use of flywheel energy storage to suppress turbine shaft over-rotation during the takeoff phase, switches to battery charging mode during the cruise phase, and optimizes the flywheel charge and discharge depth in real time to extend its mechanical life; it can ensure that the transient power buffer of the flywheel energy storage system and the steady-state output of the turbine shaft engine are coordinated.

[0020] A method of using a turbine-electric power system with flywheel energy storage:

[0021] When the aircraft is starting on the ground: both the first clutch and the second clutch are disengaged, and the turboshaft engine starts independently to a self-sustaining state;

[0022] When the aircraft is in idle condition on the ground: the first clutch is engaged, and the flywheel energy storage system is activated; at the same time, the turboshaft engine changes from a stable self-sustaining state to a speed reduction state, and its mechanical energy is partially transferred to the flywheel energy storage system, resulting in a decrease in the engine's low-pressure shaft speed; as the flywheel speed gradually approaches the turboshaft engine's low-pressure shaft speed, the energy management system predicts the speed synchronization point in advance and instructs the throttle opening to gradually decrease to a constant value, entering the speed following state mode. After the flywheel energy storage system completes energy storage, it forms a joint self-sustaining state with the turboshaft engine.

[0023] During takeoff, climb, vertical takeoff, and vertical landing: the turbine engine throttle is rapidly increased to maximum continuous output to boost power generation; the first clutch is disengaged, and the flywheel energy storage system quickly releases energy to fill the power gap; as the turbine engine power rises to its maximum value and the flywheel energy storage system energy decreases, the battery system gradually increases its output power to ensure that the total power of the three equals the load demand; after the flywheel energy storage system has exhausted its energy, the battery system output power stops increasing and remains constant; during stable operation, the sum of the turbine generator output power and the battery output power equals the electrical load demand power.

[0024] During approach and landing: the first clutch is kept engaged, the flywheel energy storage system absorbs the excess kinetic energy of the turbine motor, and the battery switches to charging mode; as the throttle continues to decrease, the turbine motor and flywheel speeds reach their peak and then gradually decrease until they reach a stable speed that matches the target power; during stable operation, the battery is in charging mode, and the output power of the turbine motor is the sum of the electrical load power and the battery charging power.

[0025] During cruise operation: the first clutch engages and the flywheel and turbine shaft rotate synchronously, the turbine motor unit operates at full power and charges the battery;

[0026] A further technical solution of the present invention is: the aircraft in two states during cruise operation:

[0027] When the electrical power consumption of the aircraft is lower than the power provided by the turbine electric power system, the throttle of the turbine shaft engine is rapidly reduced, and the rotational speed of the turbine motor and flywheel assembly increases slightly. Subsequently, the engine throttle is insufficient to maintain the increase in rotational speed, and the flywheel energy storage system begins to output electrical energy, causing the rotational speed of the turbine motor and flywheel assembly to gradually decrease. As the output power of the turbine motor gradually matches the electrical power consumption, the flywheel energy dissipation state ends, the battery charging power increases slightly, and then returns to the initial state, and the power system reaches a steady-state power balance again.

[0028] When the electrical power consumption of the aircraft exceeds the power provided by the turbine electric power system, the throttle of the turbine shaft engine increases rapidly, the clutch between the turbine shaft engine and the flywheel energy storage system disengages quickly, and the generator in the flywheel energy storage system converts mechanical energy into electrical energy to quickly respond to the power demand. The battery continues to charge, but the charging power shows a decreasing trend. As the power of the turbine motor unit gradually matches the electrical power consumption, the flywheel energy release state ends, the battery charging power gradually returns to its initial state, and the power system reaches a steady-state power balance again.

[0029] A further technical solution of the present invention is: when the power of the energy management system fluctuates, the aircraft prioritizes the scheduling of flywheel energy storage, and only calls the battery system when the flywheel energy is insufficient; when the electrical load suddenly drops, the energy management system absorbs the excess kinetic energy of the turbine shaft engine through the flywheel energy storage system; after the flywheel energy is exhausted, the battery system replenishes the remaining demand with constant power, avoiding high-frequency charging and discharging.

[0030] Beneficial effects

[0031] The beneficial effects of this invention are as follows: By deeply synergizing flywheel energy storage technology with turbine electric propulsion systems, this invention solves the industry problems of short battery life and high turbine over-spinning risk in the aviation field, while also possessing high dynamic response, long-cycle reliability, and energy-saving and environmentally friendly characteristics, providing an innovative solution for the electrification of aviation propulsion systems. Specific effects are analyzed below:

[0032] 1. This invention utilizes a flywheel energy storage system to rapidly respond to transient power fluctuations (such as a sudden increase in load during takeoff or a sudden drop in load during landing), absorbing or releasing energy to balance the power deficit or excess of the turbine shaft engine, suppressing the speed fluctuations of the turbine shaft's low-pressure shaft, effectively avoiding over-revving phenomena caused by differences in control response in traditional systems, and ensuring the safe operation of the aircraft's power system.

[0033] 2. The flywheel energy storage system of this invention can handle short-term, high-frequency power fluctuations (such as transient power compensation and energy recovery), reduce the charging and discharging frequency of lithium batteries or fuel cells, and avoid capacity decay and shortened lifespan of batteries due to high-frequency switching.

[0034] 3. The improved flywheel structure of this invention adopts a hollow disk design with concentrated mass on the outer edge, which increases the moment of inertia by 20% to 35% compared to a traditional solid flywheel of the same mass, thus enhancing the inertial compensation capability for the turbine shaft engine. Combined with a vacuum chamber environment and magnetic levitation bearing technology, the flywheel rotational loss is reduced to ≤2%, and the energy storage efficiency reaches over 95%.

[0035] 4. The energy management system of this invention dynamically allocates power according to the flight phase:

[0036] During takeoff / climb: the flywheel prioritizes releasing stored energy, the turboshaft engine gradually increases to full power, and the battery only replenishes the remaining energy.

[0037] Cruise phase: The flywheel and turbine shaft rotate synchronously, and the turbine drives the load at full power and charges the battery;

[0038] During descent: The flywheel absorbs excess kinetic energy, and the battery switches to charging mode.

[0039] 5. This invention utilizes the transient buffering capability of flywheel energy storage to reduce frequent power adjustments by the turboshaft engine, thereby lowering fuel consumption and carbon emissions. Simultaneously, the flywheel and battery serve as backups for each other, providing emergency power redundancy in the event of battery failure, ensuring a secure power supply during critical flight phases (such as landing). Attached Figure Description

[0040] Figure 1 This is a schematic diagram illustrating the working principle of a turbine electric power system with flywheel energy storage in an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram illustrating the working principle of another turbine electric power system with flywheel energy storage in an embodiment of the present invention;

[0042] Figure 3 This is a schematic diagram of the improved flywheel structure in an embodiment of the present invention;

[0043] Figure 4 Comparison of simulation results for constant speed control selected for engine control law.

[0044] Explanation of reference numerals in the attached diagram: 1. Flywheel energy storage system; 2. Vacuum chamber; 3. Bidirectional permanent magnet motor; 4. Bidirectional AC / DC rectifier; 5. Improved flywheel structure; 6. First clutch; 7. Turbine motor assembly; 8. Turbine shaft engine; 9. High-pressure shaft of the turbine shaft engine; 10. Low-pressure shaft of the turbine shaft engine; 11. Second clutch; 12. Generator; 13. Unidirectional AC / DC rectifier; 14. Battery system; 15. Hydrogen fuel cell; 16. Hydrogen storage tank; 1 7. First DC / DC converter; 18. DC electrical bus; 19. Third power distribution unit; 20. Second power distribution unit; 21. First power distribution unit; 22. Generator busbar; 23. Cable; 24. Utilizer busbar; 25. Fourth power distribution unit; 26. Sixth power distribution unit; 27. Fifth power distribution unit; 28. Second DC / DC converter; 29. ​​Second DC / AC inverter; 30. Electrical load; 31. First DC / AC inverter. Detailed Implementation

[0045] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0046] Addressing the issues of short battery life in traditional turbine electric propulsion systems and low-pressure shaft over-rotation of the turbine shaft engine due to control response differences during periods of significant electrical load fluctuations, this invention provides a turbine electric propulsion system with flywheel energy storage. The system includes a power supply module comprising a turbine motor assembly, a flywheel energy storage system, and a battery system. This power supply module is controlled by an energy management system, which coordinates the power distribution among the turbine motor assembly, flywheel energy storage system, and battery system based on flight conditions. After distribution, electrical energy is distributed to the electrical loads via an electrical bus. The turbine motor assembly includes a turbine shaft engine and a second clutch connected sequentially along the axial direction. The system comprises a turbine generator and a flywheel energy storage system. The turbine generator's low-pressure shaft is connected to the generator via a second clutch, and the generator outputs electrical energy, which is then converted to direct current by a rectifier. The flywheel energy storage system includes a bidirectional permanent magnet motor housed in a vacuum chamber and an improved flywheel structure. The bidirectional permanent magnet motor is connected to the electrical bus via a bidirectional AC / DC rectifier, and its output shaft is coaxially mounted with the improved flywheel structure. Simultaneously, the output shaft is connected to the other end of the turbine generator's low-pressure shaft via a first clutch. The battery system is connected to the electrical bus via a converter. The electrical bus isolates the generator-side busbar from the consumer-side busbar via a Distributed Power Unit (DPU). The generator-side busbar receives electrical energy from the turbine generator, battery system, and flywheel energy storage system, transmits it via cables to the consumer-side busbar, and then distributes it to the electrical loads.

[0047] Specifically, a bidirectional converter or a unidirectional converter is provided between the battery system and the power distribution unit. The bidirectional converter is a bidirectional DC / DC converter or a bidirectional DC / AC inverter, and the unidirectional converter is a unidirectional DC / DC converter or a unidirectional DC / AC inverter.

[0048] Specifically, the electrical loads include high-voltage AC loads, medium-voltage AC loads, and low-voltage DC loads. The high-voltage AC loads are connected to the electrical bus via DC / AC inverters or AC / AC converters. The medium-voltage AC loads are connected to the electrical bus via DC / AC inverters or AC / AC converters. The low-voltage DC loads are connected to the electrical bus via DC / DC converters or AC / DC rectifiers.

[0049] This invention also proposes a method for using a turbine electric propulsion system with flywheel energy storage. This method designs the clutch engagement / disengagement logic based on flight phases (such as ground start-up, idle, and cruise) to ensure synchronized rotational speeds of the flywheel and turbine shaft engine, avoiding mechanical shock. Furthermore, through a phased power distribution strategy (such as prioritizing flywheel energy release during takeoff and battery charging during cruise), real-time status identification and decision-making are achieved via an intelligent power distribution unit.

[0050] The above technical solution will be further explained below with reference to the accompanying drawings:

[0051] In one embodiment, refer to Figure 1 As shown, an aircraft turbine electric propulsion system with flywheel energy storage includes: a turbine motor unit 7, a battery system 14, a flywheel energy storage system 1, a power electronic converter, an electrical bus, and an electrical load 30. The electrical bus is connected to the turbine motor unit 7, the battery system 14, the flywheel energy storage system 1, and the electrical load 30 respectively through the power electronic converter. The turbine motor unit 7, the battery system 14, and the flywheel energy storage system 1 provide power to the electrical load 30. The turbine motor unit 7 and the battery system 14 mainly provide stable power output, while the flywheel energy storage system 1 mainly compensates for transient power fluctuations in the electrical bus.

[0052] Specifically, the turbine motor set 7 includes a turbine shaft engine 8, a generator 12, a second clutch 11, and a one-way AC / DC rectifier 13. The low-pressure shaft 10 of the turbine shaft engine 8 is connected to the generator 12 through the second clutch 11. The generator 12 is driven to generate electricity by the low-pressure shaft 10 of the turbine shaft engine. The one-way AC / DC rectifier 13 rectifies the electrical energy generated by the generator 12 and then sends it to the electrical bus.

[0053] Specifically, the flywheel energy storage system 1 includes an improved flywheel structure 5, a bidirectional permanent magnet motor 3 coaxial with the improved flywheel structure 5, a bidirectional AC / DC rectifier 4, and a vacuum chamber 2. The improved flywheel structure 5 and the bidirectional permanent magnet motor 3 are placed inside the vacuum chamber 2. The improved flywheel structure 5 is driven by the turbine shaft engine 8 in the turbine motor set 7 through the first clutch 6 to rotate and store energy. The bidirectional permanent magnet motor 3 generates electricity under the inertial rotation drive of the improved flywheel structure 5 or converts the electrical energy obtained from the bidirectional AC / DC rectifier 4 into the mechanical energy of the improved flywheel structure 5. The bidirectional AC / DC rectifier 4 rectifies the electrical energy generated by the bidirectional permanent magnet motor 3 and then sends it to the electrical bus or transmits the excess power of the electrical bus to the bidirectional permanent magnet motor 3.

[0054] Specifically, the electrical busbar includes a power distribution unit, a cable 23, a generator busbar 22, and a consumer busbar 24. The power distribution unit is directly connected to the busbar. The first power distribution unit 21, the second power distribution unit 20, and the third power distribution unit 19 respectively guide the electrical energy generated by the flywheel energy storage system 1, the turbine motor unit 7, and the battery system 14 into the generator busbar 22. The cable 23 transmits the electrical energy on the generator busbar 22 to the consumer busbar 24. The consumer busbar 24 then redistributes the electrical energy to each electrical load 30 via the fourth power distribution unit 25, the fifth power distribution unit 27, and the sixth power distribution unit 26.

[0055] Specifically, the battery system 14 uses a lithium battery; the lithium battery is connected to the electrical bus via a first DC / DC converter 17.

[0056] Specifically, in order to reduce the mass and internal resistance loss of the electrical bus, the electrical bus adopts a DC electrical bus 18. The battery system 14 is connected to the DC electrical bus 18 through a first DC / DC converter 17. The flywheel energy storage system 1 is connected to the DC electrical bus 18 through a bidirectional AC / DC rectifier 4. The turbine motor 7 is connected to the DC electrical bus 18 through a unidirectional AC / DC rectifier 13. The electrical load 30 is connected to the DC electrical bus 18 through a second DC / DC converter 28, a second DC / AC inverter 29, and a first DC / AC inverter 31.

[0057] Specifically, a second clutch 11 with engagement / disengagement function is provided between the turbine shaft engine 8 and the generator 12.

[0058] Specifically, a first clutch 6 with engagement / disengagement function is provided between the turboshaft engine 8 and the flywheel energy storage system 1.

[0059] Specifically, the generator 12 is a permanent magnet synchronous generator, which is connected to the generator controller, and the generator controller is integrated with the unidirectional AC / DC rectifier 13 in the turbine generator set 7.

[0060] Specifically, the bidirectional permanent magnet motor 3 is a permanent magnet synchronous motor. The bidirectional permanent magnet motor is connected to the bidirectional motor controller, and the bidirectional motor controller is integrated with the bidirectional AC / DC rectifier 4 in the flywheel energy storage system 1.

[0061] Specifically, the power distribution unit includes an intelligent controller and an actuator. The intelligent controller can identify the system operating status and make corresponding power distribution decisions, and the actuator can quickly perform node connection / disconnection actions based on the power distribution decisions.

[0062] In one embodiment, refer to Figure 3 As shown, the main features of the improved flywheel structure 5 are that the flywheel is integrally formed and the mass is concentrated on the outer edge of the flywheel. The inner support structure of the wheel disk adopts a hollow weight reduction treatment to ensure the overall structural strength requirements of the flywheel. The improved flywheel structure is connected and fixed to the shaft of the bidirectional permanent magnet motor through a keyway structure.

[0063] The formula for calculating the moment of inertia of the improved flywheel structure can be approximated by the formula for calculating the moment of inertia of a hollow cylinder, as follows:

[0064]

[0065] In the formula: I is the moment of inertia, m is the overall mass of the flywheel structure, R1 is the inner diameter of the flywheel structure, and R2 is the outer diameter of the flywheel structure.

[0066] In one embodiment, refer to Figure 2 As shown, this embodiment provides a turbine electric propulsion system with flywheel energy storage, including: a turbine motor unit 7 for powering the aircraft, a battery system 14, a flywheel energy storage system 1, a DC electrical bus 18, a power electronic converter, and an electrical load 30. The DC electrical bus 18 is connected to the turbine motor unit 7, the battery system 14, the flywheel energy storage system 1, and the electrical load 30 respectively through the power electronic converter. The turbine motor unit 7 and the battery system 14 provide power to the electrical load 30, and the flywheel energy storage system 1 mainly replenishes the power of the DC electrical bus 18 or absorbs the remaining power of the DC electrical bus 18 for a short period of time.

[0067] Specifically, the turbine motor set 7 includes a turbine shaft engine 8, a generator 12, a second clutch 11, and a one-way AC / DC rectifier 13. The low-pressure shaft 10 of the turbine shaft engine is connected to the second generator 12 through the second clutch 11. The generator 12 is driven to generate electricity by the low-pressure shaft 10 of the turbine shaft engine. The one-way AC / DC rectifier 13 rectifies the electrical energy generated by the generator 12 and then sends it to the DC electrical bus 18.

[0068] Specifically, the flywheel energy storage system 1 includes an improved flywheel structure 5, a bidirectional permanent magnet motor 3 coaxial with the improved flywheel structure 5, a bidirectional AC / DC rectifier 4, and a vacuum chamber 2. The improved flywheel structure 5 and the bidirectional permanent magnet motor 3 are located in the vacuum chamber 2. The improved flywheel structure 5 is driven by the turbine shaft engine 8 in the turbine motor set 7 through the first clutch 6 to rotate and store energy. The bidirectional permanent magnet motor 3 generates electricity under the inertial rotation drive of the improved flywheel structure 5. The bidirectional AC / DC rectifier 4 rectifies the electrical energy generated by the bidirectional permanent magnet motor 3 and then transmits it to the DC electrical bus 18.

[0069] Specifically, the battery system 14 includes a hydrogen fuel cell 15, a hydrogen storage tank 16, and a first DC / DC converter 17. The hydrogen storage tank 16 supplies hydrogen to the hydrogen fuel cell 15. The DC power generated by the hydrogen fuel cell 15 is boosted by the first DC / DC converter 17 and transmitted to the DC electrical bus 18. The DC electrical bus 18 includes a power distribution unit, a cable 23, a generator busbar 22, and a consumer busbar 24. The power distribution unit is directly connected to the generator busbar 22 and the consumer busbar 24. The power distribution unit guides the electrical energy generated by the turbine generator set 7, the hydrogen fuel cell system 14, and the flywheel energy storage system 1 into the generator busbar 22. The cable 23 transmits the electrical energy from the generator busbar 22 to the consumer busbar 24. The consumer busbar 24 then redistributes the electrical energy to the electrical load 30 via the power distribution unit.

[0070] Specifically, the DC electrical bus 18 is a DC bus, the hydrogen fuel cell 15 is connected to the DC electrical bus 18 through the first DC / DC converter 17, the flywheel energy storage system 1 is connected to the DC electrical bus 18 through the bidirectional AC / DC rectifier 4, the turbine motor 7 is connected to the DC electrical bus 18 through the AC / DC rectifier 13, and the electrical load 30 is connected to the electrical bus through the first DC / AC inverter 25, the second DC / AC inverter 27, and the second DC / DC converter 26.

[0071] Specifically, the flywheel energy storage system 1 works in conjunction with the turbine motor unit 7 and the battery system 14 under the coordination of the energy management system. The energy management system includes a power generation management subsystem, a power distribution management subsystem, and a load management subsystem. The power generation management subsystem provides power to the aircraft and equipment. The power distribution management subsystem controls the connection / disconnection of each power generation and consumption device to the DC electrical bus 18. The load management subsystem performs power management and load limiting on high-power consumption devices.

[0072] Specifically, the electrical load 30 includes a high-voltage AC load, a medium-voltage AC load, and a low-voltage DC load. The high-voltage AC load is connected to the DC electrical bus 18 through a first DC / AC inverter 31, the medium-voltage AC load is connected to the DC electrical bus 18 through a second DC / AC inverter 29, and the low-voltage DC load is connected to the DC electrical bus 18 through a second DC / DC converter 28.

[0073] Specifically, the turbine motor unit 7 is provided with a second clutch 11 with engagement / disengagement function between the turbine shaft engine 8 and the generator 12.

[0074] Specifically, a first clutch 6 with engagement / disengagement function is provided between the turboshaft engine 8 and the flywheel energy storage system 1.

[0075] Specifically, the engagement / disengagement function of the second clutch 11 and the first clutch 6 is realized by the clutch actuation control system, which includes a control command processor, a hydraulic actuator, a hydraulic oil tank, and hydraulic pipelines.

[0076] Specifically, the generator 12 is a permanent magnet synchronous generator, which is connected to a generator controller, and the generator controller is integrated with the unidirectional AC / DC rectifier 13.

[0077] Specifically, the bidirectional permanent magnet motor 3 is a permanent magnet synchronous motor. The bidirectional permanent magnet motor 3 is connected to the bidirectional motor controller, and the bidirectional motor controller is integrated with the bidirectional AC / DC rectifier 4 in the flywheel energy storage system 1.

[0078] Specifically, the power distribution unit includes an intelligent controller and an actuator. The intelligent controller can identify the system operating status and make corresponding power distribution decisions, and the actuator can quickly perform node connection / disconnection actions based on the power distribution decisions.

[0079] In one embodiment, a method for using the above-mentioned turbine electric power system with flywheel energy storage is as follows:

[0080] When the aircraft is in the ground start-up condition, the first clutch 6 between the turbine motor set 7 and the flywheel energy storage system 1, and the clutch between the turbine shaft engine 8 and the generator 12 in the turbine motor set 7 are all disengaged. The flywheel body 5 and the generator 12 in the turbine motor set 7 remain in an initial stationary state to ensure the rapid start-up of the turbine shaft engine 8 and its entry into a self-sustaining state. During this period, the flywheel energy storage system 1, the hydrogen fuel cell system 14 and the turbine motor set 7 neither output energy to the electrical bus 18 nor absorb energy from the electrical bus 18.

[0081] When the aircraft is in idle condition on the ground, the first clutch 6 between the turbine motor unit 7 and the flywheel energy storage system 1 engages, and the flywheel energy storage system 1 enters a rapid energy storage state. The turbine shaft engine 8 temporarily transitions from a stable self-sustaining state to a speed reduction state, and the throttle of the turbine shaft engine 8 rapidly increases to compensate for the additional energy demand generated by the energy storage system 1 and the speed fluctuations of the low-pressure shaft 10 of the turbine shaft engine. As the speed of the improved flywheel structure 5 gradually approaches that of the low-pressure shaft 10 of the turbine shaft engine, the engine throttle opening will gradually decrease and remain constant. Furthermore, the throttle opening in the constant state is higher than the throttle opening in the self-sustaining state during the start-up phase. The control response delay of the turbine shaft engine 8 will cause the flywheel body 5 and the low-pressure shaft 10 of the turbine shaft engine to gradually synchronize their speeds. The flywheel energy storage system 1 ends energy storage and enters the follow-and-hold mode. The turbine motor set 7 and the flywheel energy storage system 1 work together to enter a stable self-sustaining state. During this period, the flywheel energy storage system 1 neither outputs energy to the electrical bus 18 nor absorbs energy from the electrical bus 18. All power requirements are met by the hydrogen fuel cell system 14 and the turbine motor set 7.

[0082] When the aircraft is in takeoff, climb, vertical takeoff, and vertical landing conditions, and the instantaneous power demand of the electrical load 30 is much greater than the power provided by the turbine motor set 7 in the initial stage, the throttle of the turbine shaft engine 8 will first increase rapidly. The energy management system and the clutch braking control system will work together to first quickly disengage the clutch between the turbine shaft engine 8 and the flywheel energy storage system 1, allowing the flywheel energy storage system 1 to quickly release energy to replenish the power gap. As the power response of the turbine shaft engine 8 gradually increases and reaches its maximum continuous output value, and the energy of the flywheel energy storage system 1 gradually decreases, the fuel cell system 14 will also gradually increase its output power to replenish the power. During this period, the sum of the output power of the flywheel energy storage system 1, the turbine motor set 7, and the fuel cell system 14 is equal to the power demand of the electrical load 30. When the energy of the flywheel energy storage system 1 is gradually released, the output power of the hydrogen fuel cell system 14 will stop increasing and enter a constant state. During stable operation, the sum of the output power of the turbine motor set 7 and the output power of the hydrogen fuel cell system 14 is equal to the power demand of the electrical load 30.

[0083] During the approach and landing phases of the aircraft, the power of the electrical load 30 decreases significantly in the initial stage. When the power provided by the turbine motor 7 and the hydrogen fuel cell system 14 far exceeds the power demand of the electrical load 30, the throttle of the turbine shaft engine 8 decreases rapidly. The hydrogen supply from the hydrogen storage tank 16 in the hydrogen fuel cell system 14 also gradually decreases, leading to a gradual decrease in the output power of the hydrogen fuel cell system 14. The energy management system and the clutch-operated control system work in concert, and the first clutch 6 between the turbine motor 7 and the flywheel energy storage system 1 remains engaged to prevent over-rotation of the low-pressure shaft 10 of the turbine shaft engine due to excess power during the control response lag. During the control response lag, most of the power demand of the electrical load 30 is provided by the hydrogen fuel cell system 14, and a small portion is provided by the turbine motor 7. The flywheel energy storage system 1 only absorbs power and does not output power. As the throttle gradually decreases, the low-pressure shaft of the turbine shaft engine... After the speed of the pressure shaft 10 and the flywheel body 5 reaches its peak, it gradually decreases. The first clutch 6 will disengage when the speed reaches its peak, and the low-pressure shaft 10 of the turbine engine and the flywheel body 5 will enter a separate and independent operation state. As the throttle decreases, the turbine engine 8 will gradually enter a stable operating state that matches the output power. If the power provided by the turbine motor set 7 and the hydrogen fuel cell system 14 is still greater than the power required by the electrical load 30 when the throttle of the turbine engine 8 reaches the minimum self-sustaining state, the hydrogen supply of the hydrogen fuel cell system 14 will continue to be reduced to reduce its output power. During this period, the flywheel energy storage system 1 will absorb the excess power generated by the hydrogen fuel cell system 14 from the electrical bus 18. During stable operation, the power demand of the electrical load 30 will be met by the turbine motor set 7 and the hydrogen fuel cell system 14 together or by the hydrogen fuel cell system 14 alone, depending on the difference between the actual power demand and the power system design parameters.

[0084] In this embodiment, when the aircraft is cruising normally, the first clutch 6 between the flywheel energy storage system 1 and the turbine motor 7 is engaged and keeps rotating synchronously. The flywheel energy storage system 1 does not output power to the electrical bus 18. At this time, the turbine motor 7 maintains a low power level operation, and the hydrogen fuel cell system 14 operates at full power. The power demand of the electrical load 30 will be met by the turbine motor 7 and the hydrogen fuel cell system 14.

[0085] In this embodiment, during the aircraft's cruise, when the aircraft's electrical power consumption is lower than the power provided by the turbine electric power system, the throttle of the turbine shaft engine 8 is rapidly reduced, while the hydrogen fuel cell system 14 maintains full-power operation. A portion of the short-term excess mechanical energy from the turbine shaft engine 8 is transferred to the flywheel energy storage system 1 via the first clutch 6 for storage, and the other portion is converted into electrical energy by the generator 12 in the turbine motor assembly 7. This electrical energy is then transmitted to the generator-end busbar 22 via the second power distribution unit 20. The electrical energy generated by the hydrogen fuel cell system 14 is transmitted to the generator-end busbar 22 via the third power distribution unit 19. After prioritizing the electrical load 30, the generator-end busbar 22 transmits the remaining power to the improved flywheel structure 5 for storage via the first power distribution unit 21, the bidirectional AC / DC rectifier 4, and the bidirectional permanent magnet motor 3. As the output power of the turbine motor assembly 7, the output power of the hydrogen fuel cell system 14, and the electrical power consumption gradually match, the energy storage state of the flywheel energy storage system 1 ends, and the power system reaches a power balance state again.

[0086] In this embodiment, during the aircraft's cruise, when the aircraft's electrical power consumption exceeds the power provided by the turbine electric power system, the throttle of the turbine shaft engine 8 rapidly increases, the hydrogen fuel cell system 14 maintains full-power operation, and the first clutch 6 between the turbine shaft engine 8 and the flywheel energy storage system 1 quickly disengages. The reversible electric motor / generator 3 in the flywheel energy storage system 1 converts mechanical energy into electrical energy to quickly respond to power demands. When the turbine shaft engine 8's throttle increases enough to fully compensate for the power shortfall, the flywheel energy storage system 1's energy release state ends. At this point, the output power of the turbine motor 7 and the hydrogen fuel cell system 14 equals the power demand of the electrical load 30, and the power system returns to a stable state. Subsequently, the first clutch 6 will engage again, allowing the flywheel energy storage system 1 and the turbine motor 7 to operate together once more.

[0087] Specifically, the energy management system includes a power generation management system, a load management system, and a power distribution management system. The power generation management subsystem provides power to the aircraft and its equipment. The power distribution management subsystem controls the connection / disconnection of each power generation and consumption device to the electrical bus. The load management subsystem performs power management and load limiting on high-power consumption devices.

[0088] Specifically, the said clutch actuator control system includes a control command processor, a hydraulic actuator, a hydraulic oil tank, and hydraulic pipelines.

[0089] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A turbine-electric power system with flywheel energy storage, characterized in that: It includes a power supply module consisting of a turbine motor unit, a flywheel energy storage system, and a battery system. The power supply module is controlled by an energy management system, which coordinates the power distribution of the turbine motor unit, the flywheel energy storage system, and the battery system according to the flight conditions. After distribution, the power is distributed to the electrical loads through the electrical bus. The turbine generator set includes a turbine shaft engine, a second clutch, and a generator connected in sequence along the axial direction; one end of the low-pressure shaft of the turbine shaft engine is connected to the generator through the second clutch, and the electrical energy output by the generator is converted into direct current by a rectifier. The flywheel energy storage system includes a bidirectional permanent magnet motor and an improved flywheel structure placed inside a vacuum chamber; the bidirectional permanent magnet motor is connected to the electrical bus via a bidirectional AC / DC rectifier, and the improved flywheel structure is coaxially mounted on its output shaft, while the output shaft is connected to the other end of the low-pressure shaft of the turbine engine via a first clutch; the improved flywheel structure is a centrally hollowed-out disc with mass concentrated on the outer edge. The battery system is connected to the electrical bus via a converter; The electrical busbar isolates the generator busbar from the consumer busbar through the power distribution unit. The generator busbar receives electrical energy from the turbine generator set, battery system and flywheel energy storage system, and transmits it to the consumer busbar via cable before distributing it to the electrical load. The energy management system performs dynamic power allocation, prioritizing the use of flywheel energy storage to suppress turbine shaft over-rotation during takeoff, switching to battery charging mode during cruise, and optimizing flywheel charge and discharge depth in real time to extend its mechanical life. It can ensure that the transient power buffer of the flywheel energy storage system is coordinated with the steady-state output of the turbine shaft engine.

2. The turbine-electric power system with flywheel energy storage according to claim 1, characterized in that: The rotational inertia of the improved flywheel structure satisfies: in, For rotational inertia, To improve the overall quality of the flywheel structure, To improve the inner diameter of the outer edge of the flywheel structure, To improve the outer diameter of the flywheel structure.

3. The turbine-electric power system with flywheel energy storage according to claim 1, characterized in that: The battery system is a fuel cell, connected to a hydrogen storage tank and connected to an electrical bus via a unidirectional converter; the unidirectional converter is a unidirectional DC / DC converter or a unidirectional DC / AC inverter. It may be a lithium battery, connected to the electrical bus via a bidirectional converter; the bidirectional converter is a bidirectional DC / DC converter or a bidirectional DC / AC inverter.

4. The turbine-electric power system with flywheel energy storage according to claim 1, characterized in that: The electrical bus is a DC electrical bus. The battery system is connected to the DC electrical bus through a DC / DC converter. The flywheel energy storage system is connected to the DC electrical bus through an AC / DC rectifier. The turbine motor is connected to the DC electrical bus through an AC / DC rectifier. The electrical load is connected to the DC electrical bus through a DC / AC inverter, a DC / AC inverter, and a DC / DC converter.

5. The turbine-electric power system with flywheel energy storage according to claim 1, characterized in that: The electrical loads include high-voltage AC loads, medium-voltage AC loads, and low-voltage DC loads. The high-voltage AC loads are connected to the electrical bus via DC / AC inverters or AC / AC converters. The medium-voltage AC loads are connected to the electrical bus via DC / AC inverters or AC / AC converters. The low-voltage DC loads are connected to the electrical bus via DC / DC converters or AC / DC rectifiers.

6. The turbine-electric power system with flywheel energy storage according to claim 1, characterized in that: Both the first clutch and the second clutch have engagement / disengagement functions, and the clutch status is adjusted in real time according to the turbine shaft engine speed, flywheel speed and electrical load power requirements.

7. A method of using the turbine electric power system with flywheel energy storage as described in any one of claims 1-6, characterized in that: When the aircraft is starting on the ground: both the first clutch and the second clutch are disengaged, and the turboshaft engine starts independently to a self-sustaining state; When the aircraft is in idle condition on the ground: the first clutch is engaged, and the flywheel energy storage system is activated; at the same time, the turboshaft engine changes from a stable self-sustaining state to a speed reduction state, and its mechanical energy is partially transferred to the flywheel energy storage system, resulting in a decrease in the engine's low-pressure shaft speed; as the flywheel speed gradually approaches the turboshaft engine's low-pressure shaft speed, the energy management system predicts the speed synchronization point in advance and instructs the throttle opening to gradually decrease to a constant value, entering the speed following state mode. After the flywheel energy storage system completes energy storage, it forms a joint self-sustaining state with the turboshaft engine. During aircraft takeoff, climb, vertical takeoff, and vertical landing: the turbine engine throttle is rapidly increased to maximum continuous output to boost power generation; the first clutch is disengaged, and the flywheel energy storage system quickly releases energy to fill the power gap; as the turbine engine power rises to its maximum value and the flywheel energy storage system energy decreases, the battery system gradually increases its output power to ensure that the total power of the three equals the load demand; after the flywheel energy storage system has exhausted its energy, the battery system output power stops increasing and remains constant; during stable operation, the sum of the turbine generator output power and the battery output power equals the electrical load demand power; During approach and landing: the first clutch is kept engaged, the flywheel energy storage system absorbs the excess kinetic energy of the turbine motor, and the battery switches to charging mode; as the throttle continues to decrease, the turbine motor and flywheel speeds reach their peak and then gradually decrease until they reach a stable speed that matches the target power; during stable operation, the battery is in charging mode, and the output power of the turbine motor is the sum of the electrical load power and the battery charging power. During cruise operation: the first clutch engages and the flywheel and turbine shaft rotate synchronously, the turbine motor unit operates at full power and charges the battery.

8. The method of use according to claim 7, characterized in that: The aircraft operates in two scenarios during cruise mode: When the electrical power consumption of the aircraft is lower than the power provided by the turbine electric power system, the throttle of the turbine shaft engine is rapidly reduced, and the rotational speed of the turbine motor and flywheel assembly increases slightly. Subsequently, the engine throttle is insufficient to maintain the increase in rotational speed, and the flywheel energy storage system begins to output electrical energy, causing the rotational speed of the turbine motor and flywheel assembly to gradually decrease. As the output power of the turbine motor gradually matches the electrical power consumption, the flywheel energy dissipation state ends, the battery charging power increases slightly, and then returns to the initial state, and the power system reaches a steady-state power balance again. When the electrical power consumption of the aircraft exceeds the power provided by the turbine electric power system, the throttle of the turbine shaft engine increases rapidly, the clutch between the turbine shaft engine and the flywheel energy storage system disengages quickly, and the generator in the flywheel energy storage system converts mechanical energy into electrical energy to quickly respond to the power demand. The battery continues to charge, but the charging power shows a decreasing trend. As the power of the turbine motor unit gradually matches the electrical power consumption, the flywheel energy release state ends, the battery charging power gradually returns to its initial state, and the power system reaches a steady-state power balance again.

9. The method of use according to claim 7, characterized in that: When the power of the energy management system fluctuates, the aircraft prioritizes the use of flywheel energy storage and only calls upon the battery system when the flywheel energy is insufficient. When the electrical load suddenly drops, the energy management system absorbs the excess kinetic energy of the turbine engine through the flywheel energy storage system. After the flywheel energy is depleted, the battery system replenishes the remaining demand with a constant power, avoiding high-frequency charging and discharging.

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