Hydrogen energy aircraft endurance time estimation method

Abstract

This invention discloses a method for estimating the flight time of a hydrogen-powered aircraft, belonging to the field of energy management technology. The method includes the following steps: S1, calculating the available hydrogen mass in the hydrogen storage tank at the initial moment of flight; S2, calculating the available hydrogen mass in the hydrogen storage tank at the current moment; S3, calculating the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period; S4, obtaining a hydrogen energy conversion efficiency dataset; S5, finding the target hydrogen energy conversion efficiency corresponding to the target power requirement; S6, calculating the remaining flight time of the aircraft based on the available hydrogen mass in the hydrogen storage tank at the current moment, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the remaining available power of the lithium battery at the current moment, and the target power requirement. This invention fully considers the influence of hydrogen temperature, hydrogen pressure, and hydrogen compressibility factor within the hydrogen storage tank, making the calculation of the hydrogen mass in the storage tank more accurate, thereby improving the accuracy of subsequent calculations of hydrogen consumption rate and remaining flight time.

Description

Technical Field

[0001] This invention relates to the field of energy management technology, and in particular to a method for estimating the flight time of a hydrogen-powered aircraft. Background Technology

[0002] With energy transition and environmental protection requirements, the aviation industry is gradually moving towards green and electric directions. New energy forms such as hydrogen energy, lithium batteries, and solar energy are beginning to be used as energy sources to drive various airborne electrical equipment. Among them, hydrogen energy, as a highly efficient and clean secondary energy source, is a strong candidate for future aviation energy. In particular, using hydrogen fuel cells to directly generate electricity to drive motors instead of traditional aviation fuel can effectively improve aircraft flight efficiency and reduce pollution and noise. A hydrogen fuel cell is a power generation device that directly converts the chemical energy of hydrogen into electrical energy through an electrochemical reaction.

[0003] Currently, aircraft powered primarily by hydrogen energy have received considerable research attention, particularly with significant advancements in energy conversion technologies utilizing high-pressure gaseous hydrogen storage combined with hydrogen fuel cells. However, due to factors such as storage methods, operating environments, measurement challenges, and energy system weight requirements, established methods for measuring fuel quantity and consumption rates in traditional aviation fuels cannot be applied to hydrogen-powered aircraft. While hydrogen energy and hydrogen fuel cell technology are widely used in automobiles, and considerable research has been conducted on online hydrogen consumption rates and driving range for hydrogen fuel cell vehicles, with corresponding methods developed, there are currently no mature and reliable methods for calculating hydrogen consumption rates, flight time, and driving range for hydrogen-powered aircraft.

[0004] The current estimates of the remaining hydrogen volume in hydrogen storage tanks and the hydrogen consumption rate for hydrogen-powered aircraft are inaccurate. The hydrogen energy conversion efficiency has not been calculated and corrected, and the contribution of lithium battery energy to the range has not been considered, resulting in a large deviation in the estimated range.

[0005] Chinese patent document CN106324511A, published on January 11, 2017, discloses a method for estimating the flight time of a hydrogen fuel cell drone. The specific steps are as follows:

[0006] Step 1: The drone is equipped with an air tank. During the drone's stable flight, the pressure of the air tank on the drone and the known capacity of the air tank are collected to calculate the remaining energy of the air tank.

[0007] Step 2: Based on the remaining energy in the gas tank and the energy conversion efficiency of the proton exchange membrane hydrogen fuel cell, the usable energy of the drone can be obtained.

[0008] Step 3: During the drone's flight, collect the output current and voltage values ​​of the hydrogen fuel cell at various times, and calculate the average discharge current and average discharge voltage during the drone's flight.

[0009] Step 4: Calculate the average output power of the UAV during flight based on the average current and voltage data;

[0010] Step 5: Based on the average output power of the hydrogen fuel cell drone and the available energy of the drone, the remaining flight time of the drone during the real-time flight mission is obtained.

[0011] The patent document discloses a method for estimating the flight time of hydrogen fuel cell drones. This method estimates the drone's flight time in real time by taking into account the gas tank pressure and a series of other actual measured values, thus significantly improving the reliability, practicality, and safety of the drone equipment. However, because the remaining energy estimation only considers the gas tank pressure and does not take into account the effects of temperature and hydrogen compressibility factor, the estimated remaining flight time is inaccurate. Summary of the Invention

[0012] To overcome the shortcomings of the prior art, this invention provides a method for estimating the flight time of hydrogen-powered aircraft. This invention fully considers the effects of hydrogen temperature, hydrogen pressure, and hydrogen compressibility factor in the hydrogen storage tank, making the calculation of hydrogen mass in the storage tank more accurate, thereby improving the accuracy of subsequent hydrogen consumption rate and remaining flight time calculation.

[0013] This invention is achieved through the following technical solution:

[0014] A method for estimating the range of a hydrogen-powered aircraft includes the following steps:

[0015] S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight.

[0016] S2. Obtain the remaining usable power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment;

[0017] S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period;

[0018] S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset.

[0019] S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0020] S6. Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0021] In S1, the hydrogen storage tank at the initial moment of flight can be calculated using the hydrogen mass via Equation 1;

[0022] Formula 1;

[0023] in, The mass of hydrogen available in the hydrogen storage tank at the initial moment of flight. m The molar mass of hydrogen gas is... V This refers to the volume of the hydrogen storage tank. R Let be the ideal gas constant. The pressure of the hydrogen storage tank at the initial moment of flight. The temperature of the hydrogen storage tank at the initial moment of flight. for and Hydrogen compressibility under certain conditions The minimum usable pressure for the hydrogen storage tank. The minimum usable pressure and temperature allowed for the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0024] In S2, the hydrogen storage tank at the current moment can be calculated using the hydrogen mass via Equation 2;

[0025] Formula 2;

[0026] in, This represents the current mass of hydrogen available in the hydrogen storage tank. The current pressure of the hydrogen storage tank. The current temperature of the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0027] In S3, the average hydrogen consumption rate during flight is calculated using Equation 3;

[0028] Formula 3;

[0029] in, This represents the average hydrogen consumption rate during flight. For the current moment, This is the initial moment of flight.

[0030] In S3, the hydrogen consumption rate in the current calculation cycle is calculated using Equation 4;

[0031] Equation 4;

[0032] in, This represents the hydrogen consumption rate during the current calculation period. This is the end time of the previous cycle. This represents the mass of hydrogen available in the hydrogen storage tank at the end of the previous cycle.

[0033] In S4, the average hydrogen energy conversion efficiency during flight is calculated using Equation 5;

[0034] Formula 5;

[0035] in, This represents the average hydrogen energy conversion efficiency during flight. This represents the average output power of the hydrogen fuel cell during flight. It has a low calorific value, which is due to hydrogen.

[0036] In S4, the hydrogen energy conversion efficiency within the current calculation cycle is calculated using Equation 6;

[0037] Formula 6;

[0038] in, This represents the hydrogen energy conversion efficiency within the current calculation cycle. This represents the average output power of the hydrogen fuel cell during the current cycle.

[0039] In S5, the target power requirement refers to the target power output by the aircraft based on the power consumption of all current airborne mission loads to meet the current flight mission phase.

[0040] In S6, the remaining flight time of the aircraft is calculated using Equation 7;

[0041] Formula 7;

[0042] in, D This refers to the remaining flight time of the aircraft. The target hydrogen energy conversion efficiency This represents the remaining usable charge of the lithium battery at the current moment. The target power requirement.

[0043] In step S5, finding the target hydrogen energy conversion efficiency corresponding to the target power demand refers to finding it by fitting a hydrogen energy conversion efficiency dataset and then searching based on the fitted curve.

[0044] The beneficial effects of this invention are mainly reflected in the following aspects:

[0045] 1. Compared with the prior art, the present invention fully considers the influence of hydrogen temperature, hydrogen pressure and hydrogen compressibility factor in the hydrogen storage tank, making the calculation of hydrogen mass in the hydrogen storage tank more accurate, thereby improving the accuracy of subsequent hydrogen consumption rate and remaining driving time calculation.

[0046] 2. This invention achieves dynamic updates and continuous corrections to the hydrogen consumption rate by calculating the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period, as well as the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation period. It also considers the energy replenishment and consumption of lithium batteries, enabling the calculation of aircraft range to be dynamically updated with high accuracy.

[0047] 3. This invention eliminates the need for an additional hydrogen fuel flow measurement device; instead, it directly calculates the hydrogen consumption rate, thereby reducing aircraft weight and improving flight time.

[0048] 4. This invention, by combining average energy consumption calculation and segmented energy consumption calculation, can adapt to flight time calculation under different power requirements of the aircraft in steady state and dynamic conditions, improve the versatility of the calculation model, and has the ability to adapt to complex flight conditions.

[0049] 5. Compared with the static hydrogen energy conversion efficiency data of the prior art, the present invention finds the target hydrogen energy conversion efficiency corresponding to the target required power by searching the hydrogen energy conversion efficiency dataset, and obtains dynamic hydrogen energy conversion efficiency data, which can ensure real-time performance and accuracy.

[0050] 6. This invention, based on the comprehensive utilization of hydrogen energy and lithium battery energy, and the real-time calculation of remaining flight time linked with the target power demand, can effectively improve energy utilization efficiency and contribute to the improvement of flight time. Attached Figure Description

[0051] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments:

[0052] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0053] Example 1

[0054] See Figure 1 A method for estimating the range of a hydrogen-powered aircraft includes the following steps:

[0055] S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight.

[0056] S2. Obtain the remaining available power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment;

[0057] S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period;

[0058] S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset.

[0059] S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0060] S6. Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0061] This embodiment is the most basic implementation method. Compared with the prior art, it fully considers the effects of hydrogen temperature, hydrogen pressure and hydrogen compressibility factor in the hydrogen storage tank, making the calculation of hydrogen mass in the hydrogen storage tank more accurate, thereby improving the accuracy of subsequent hydrogen consumption rate and remaining driving time calculation.

[0062] Example 2

[0063] See Figure 1 A method for estimating the range of a hydrogen-powered aircraft includes the following steps:

[0064] S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight.

[0065] S2. Obtain the remaining available power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment;

[0066] S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period;

[0067] S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset.

[0068] S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0069] S6. Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0070] In S1, the hydrogen storage tank at the initial moment of flight can be calculated using the hydrogen mass via Equation 1;

[0071] Formula 1;

[0072] in, The mass of hydrogen available in the hydrogen storage tank at the initial moment of flight. m The molar mass of hydrogen gas is... V This refers to the volume of the hydrogen storage tank. R Let be the ideal gas constant. The pressure of the hydrogen storage tank at the initial moment of flight. The temperature of the hydrogen storage tank at the initial moment of flight. for and Hydrogen compressibility factor under certain conditions The minimum usable pressure for the hydrogen storage tank. The minimum usable pressure and temperature allowed for the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0073] In S2, the hydrogen storage tank at the current moment can be calculated using the hydrogen mass via Equation 2;

[0074] Formula 2;

[0075] in, This represents the current mass of hydrogen available in the hydrogen storage tank. The current pressure of the hydrogen storage tank. The current temperature of the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0076] This embodiment is a preferred implementation. By calculating the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation cycle, as well as the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle, dynamic updates are achieved, and the hydrogen consumption rate is continuously corrected. Energy conversion calculations and verifications are performed using hydrogen fuel cell data and hydrogen storage tank data, and the energy replenishment and consumption of lithium batteries are taken into account, so that the aircraft's flight time calculation can be dynamically updated and has high accuracy.

[0077] Example 3

[0078] See Figure 1 A method for estimating the range of a hydrogen-powered aircraft includes the following steps:

[0079] S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight.

[0080] S2. Obtain the remaining available power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment;

[0081] S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period;

[0082] S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset.

[0083] S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0084] S6. Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0085] In S1, the hydrogen storage tank at the initial moment of flight can be calculated using the hydrogen mass via Equation 1;

[0086] Formula 1;

[0087] in, The mass of hydrogen available in the hydrogen storage tank at the initial moment of flight. m The molar mass of hydrogen gas is... V This refers to the volume of the hydrogen storage tank. R Let be the ideal gas constant. The pressure of the hydrogen storage tank at the initial moment of flight. The temperature of the hydrogen storage tank at the initial moment of flight. for and Hydrogen compressibility under certain conditions The minimum usable pressure for the hydrogen storage tank. The minimum usable pressure and temperature allowed for the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0088] In S2, the hydrogen storage tank at the current moment can be calculated using the hydrogen mass via Equation 2;

[0089] Formula 2;

[0090] in, This represents the current mass of hydrogen available in the hydrogen storage tank. The current pressure of the hydrogen storage tank. The current temperature of the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0091] In S3, the average hydrogen consumption rate during flight is calculated using Equation 3;

[0092] Formula 3;

[0093] in, This represents the average hydrogen consumption rate during flight. For the current moment, This is the initial moment of flight.

[0094] In S3, the hydrogen consumption rate in the current calculation cycle is calculated using Equation 4;

[0095] Equation 4;

[0096] in, This represents the hydrogen consumption rate during the current calculation period. This is the end time of the previous cycle. This represents the mass of hydrogen available in the hydrogen storage tank at the end of the previous cycle.

[0097] This embodiment is another preferred implementation method. It does not require the installation of an additional hydrogen fuel flow measurement device, but directly calculates the hydrogen consumption rate, thereby reducing the aircraft weight and improving the aircraft's flight time.

[0098] Example 4

[0099] See Figure 1 A method for estimating the range of a hydrogen-powered aircraft includes the following steps:

[0100] S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight.

[0101] S2. Obtain the remaining usable power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment;

[0102] S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period;

[0103] S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset.

[0104] S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0105] S6. Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0106] In S1, the hydrogen storage tank at the initial moment of flight can be calculated using the hydrogen mass via Equation 1;

[0107] Formula 1;

[0108] in, The mass of hydrogen available in the hydrogen storage tank at the initial moment of flight. m The molar mass of hydrogen gas is... V This refers to the volume of the hydrogen storage tank. R Let be the ideal gas constant. The pressure of the hydrogen storage tank at the initial moment of flight. The temperature of the hydrogen storage tank at the initial moment of flight. for and Hydrogen compressibility factor under certain conditions The minimum usable pressure for the hydrogen storage tank. The minimum usable pressure and temperature allowed for the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0109] In S2, the hydrogen storage tank at the current moment can be calculated using the hydrogen mass via Equation 2;

[0110] Formula 2;

[0111] in, This represents the current mass of hydrogen available in the hydrogen storage tank. The current pressure of the hydrogen storage tank. The current temperature of the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

[0112] In S3, the average hydrogen consumption rate during flight is calculated using Equation 3;

[0113] Formula 3;

[0114] in, This represents the average hydrogen consumption rate during flight. For the current moment, This is the initial moment of flight.

[0115] In S3, the hydrogen consumption rate in the current calculation cycle is calculated using Equation 4;

[0116] Equation 4;

[0117] in, This represents the hydrogen consumption rate during the current calculation period. This is the end time of the previous cycle. This represents the mass of hydrogen available in the hydrogen storage tank at the end of the previous cycle.

[0118] In S4, the average hydrogen energy conversion efficiency during flight is calculated using Equation 5;

[0119] Formula 5;

[0120] in, This represents the average hydrogen energy conversion efficiency during flight. This represents the average output power of the hydrogen fuel cell during flight. It has a low calorific value, which is due to hydrogen.

[0121] In S4, the hydrogen energy conversion efficiency within the current calculation cycle is calculated using Equation 6;

[0122] Formula 6;

[0123] in, This represents the hydrogen energy conversion efficiency within the current calculation cycle. This represents the average output power of the hydrogen fuel cell during the current cycle.

[0124] In S5, the target power requirement refers to the target power output by the aircraft based on the power consumption of all current airborne mission loads to meet the current flight mission phase.

[0125] In S6, the remaining flight time of the aircraft is calculated using Equation 7;

[0126] Formula 7;

[0127] in, D This refers to the remaining flight time of the aircraft. The target hydrogen energy conversion efficiency. This represents the remaining usable charge of the lithium battery at the current moment. The target power requirement.

[0128] In step S5, finding the target hydrogen energy conversion efficiency corresponding to the target power demand refers to finding it by fitting a hydrogen energy conversion efficiency dataset and then searching based on the fitted curve.

[0129] This embodiment is the optimal implementation method. By combining average energy consumption calculation and segmented energy consumption calculation, it can adapt to flight time calculation under different power requirements of the aircraft in steady state and dynamic states, improve the versatility of the calculation model, and has the ability to adapt to complex flight conditions.

[0130] Compared to existing static hydrogen energy conversion efficiency data, this invention uses a hydrogen energy conversion efficiency dataset to find the target hydrogen energy conversion efficiency corresponding to the target required power, thus obtaining dynamic hydrogen energy conversion efficiency data, which ensures real-time performance and accuracy.

[0131] By integrating hydrogen energy and lithium battery energy, and linking the real-time calculated remaining flight time with the target power demand, energy utilization efficiency can be effectively improved, which helps to increase flight time.

[0132] The invention will now be illustrated with specific examples:

[0133] Step S01: Obtain the remaining usable lithium battery power at the initial moment of flight and calculate the initial flight time.

[0134] The initial available hydrogen mass in the hydrogen storage tank is determined using the aircraft's takeoff time as the initial moment. The remaining available power of the lithium battery is obtained through the lithium battery power calculation unit. The initial available hydrogen mass in the hydrogen storage tank is calculated using the formula... The calculation yielded that, m The molar mass of hydrogen is 2.016 g / mol. V This refers to the volumetric pressure of the hydrogen storage tank, in L (liters). R The gas constant is 0.008314 MPa·L / (mol·K); the applicable range of P is 0.1 MPa-100 MPa; temperature T Its applicable range is 220K-500K; compressibility factor Z Calculated according to Appendix A.6 of GB / T 35178;

[0135] Step S02: Obtain the remaining usable capacity of the lithium battery at the current moment, and calculate the hydrogen storage capacity at the current moment.

[0136] The mass of hydrogen available in the tank; the calculation method and applicable scope of SO1 in the same step;

[0137] Step S03: Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate during the current calculation period.

[0138] Gas consumption rate, through and Calculate the hydrogen consumption rate, with the unit being g / h, and the calculation time period can range from minutes to hours;

[0139] Step S04: Calculate the average hydrogen energy conversion efficiency during flight and the efficiency within the current calculation period.

[0140] The hydrogen energy conversion efficiency, the hydrogen energy conversion efficiency is determined by and

[0141] The calculation yielded, where The average output power of the hydrogen fuel cell over a period of time can be calculated from the average value of the product of the output current and voltage of the hydrogen fuel cell over a period of time, and the unit is W; The lower calorific value of hydrogen is 33.33 W·h / g.

[0142] Step S05: By using the target power required for the next stage of flight output by the aircraft, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4.

[0143] Step S06: Calculate the remaining flight time of the aircraft based on the current available hydrogen mass in the hydrogen storage tank, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the current remaining available power of the lithium battery, and the target power requirement.

[0144] pass Calculate the aircraft's remaining flight time;

[0145] in, D This refers to the remaining flight time of the aircraft. The target hydrogen energy conversion efficiency. This represents the remaining usable charge of the lithium battery at the current moment. The target power requirement.

Claims

1. A method for estimating the range of a hydrogen-powered aircraft, characterized in that, Includes the following steps: S1. Obtain the remaining available power of the lithium battery at the initial moment of flight and calculate the available hydrogen mass in the hydrogen storage tank at the initial moment of flight. S2. Obtain the remaining available power of the lithium battery at the current moment, and calculate the available hydrogen mass in the hydrogen storage tank at the current moment; S3. Calculate the average hydrogen consumption rate during flight and the hydrogen consumption rate within the current calculation period; S4. Calculate the average hydrogen energy conversion efficiency during flight and the hydrogen energy conversion efficiency within the current calculation cycle to obtain the hydrogen energy conversion efficiency dataset. S5. By outputting the target power required for the next stage of flight during the flight, the target hydrogen energy conversion efficiency corresponding to the target power is found using the hydrogen energy conversion efficiency dataset obtained in S4. S6. Calculate the remaining flight time of the aircraft based on the available hydrogen mass in the hydrogen storage tank at the current moment, the lower calorific value of hydrogen, the target hydrogen energy conversion efficiency, the remaining available power of the lithium battery at the current moment, and the target power requirement. In S5, the target required power refers to the target power output by the aircraft based on the power consumption of all current airborne mission loads to meet the current flight mission phase. In step S5, finding the target hydrogen energy conversion efficiency corresponding to the target power demand refers to finding it by fitting a hydrogen energy conversion efficiency dataset and searching based on the fitted curve. In S6, the remaining flight time of the aircraft is calculated using Equation 7; Formula 7; in, D This refers to the remaining flight time of the aircraft. This represents the current mass of hydrogen available in the hydrogen storage tank. Hydrogen has a low calorific value. The target hydrogen energy conversion efficiency This represents the remaining usable charge of the lithium battery at the current moment. The target power requirement.

2. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 1, characterized in that: In S1, the hydrogen storage tank at the initial moment of flight can be calculated using the hydrogen mass via Equation 1; Formula 1; in, The mass of hydrogen available in the hydrogen storage tank at the initial moment of flight. m The molar mass of hydrogen gas is... V This refers to the volume of the hydrogen storage tank. R Let be the ideal gas constant. The pressure of the hydrogen storage tank at the initial moment of flight. The temperature of the hydrogen storage tank at the initial moment of flight. for and Hydrogen compressibility under certain conditions The minimum usable pressure for the hydrogen storage tank. The minimum usable pressure and temperature allowed for the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

3. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 2, characterized in that: In S2, the hydrogen storage tank at the current moment can be calculated using the hydrogen mass via Equation 2; Formula 2; in, This represents the current mass of hydrogen available in the hydrogen storage tank. The current pressure of the hydrogen storage tank. The current temperature of the hydrogen storage tank. for and Hydrogen compressibility factor under certain conditions.

4. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 3, characterized in that: In S3, the average hydrogen consumption rate during flight is calculated using Equation 3; Formula 3; in, This represents the average hydrogen consumption rate during flight. For the current moment, This is the initial moment of flight.

5. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 4, characterized in that: In S3, the hydrogen consumption rate in the current calculation cycle is calculated using Equation 4; Equation 4; in, This represents the hydrogen consumption rate during the current calculation period. This is the end time of the previous cycle. This represents the mass of hydrogen available in the hydrogen storage tank at the end of the previous cycle.

6. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 5, characterized in that: In S4, the average hydrogen energy conversion efficiency during flight is calculated using Equation 5; Formula 5; in, This represents the average hydrogen energy conversion efficiency during flight. This represents the average output power of the hydrogen fuel cell during flight. It has a low calorific value, which is due to hydrogen.

7. The method for estimating the flight time of a hydrogen-powered aircraft according to claim 6, characterized in that: In S4, the hydrogen energy conversion efficiency within the current calculation cycle is calculated using Equation 6; Formula 6; in, This represents the hydrogen energy conversion efficiency within the current calculation cycle. This represents the average output power of the hydrogen fuel cell during the current cycle.

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