An electric vertical take-off and landing aircraft profile-operation-power system combined optimization design method

Abstract

The application provides a joint optimization design method for a profile-operation-power system of an electric vertical take-off and landing aircraft, which defines power system design variables, profile design variables and operation optimization variables of the electric vertical take-off and landing aircraft; establishes a power system mass model, an aircraft profile demand analysis model, a variable-pitch propeller operation performance model and a motor operation performance model; combines power system design and operation control planning of the electric vertical take-off and landing aircraft, realizes joint optimization design of the profile-operation-power system of the electric vertical take-off and landing aircraft, and maximally considers the wide-speed domain operation characteristics of the variable-pitch propeller and the characteristics of huge differences between the hovering and cruising flight stages of the vertical take-off aircraft. Compared with the prior physical system design and the subsequent operation control design, the overall performance of the aircraft is optimized.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, specifically a method for joint optimization design of profile, operation, and power system of an electric vertical takeoff and landing aircraft. Background Technology

[0002] Electric vertical take-off and landing (eVTOL) aircraft, as an emerging mode of air transportation, are gradually becoming one of the key technologies for the development of the low-altitude economy. eVTOL aircraft offer advantages such as vertical take-off and landing, high-efficiency cruise, low noise, and low emissions, making them suitable for urban air travel, emergency medical rescue, and cargo transportation. Therefore, they have attracted significant attention from aviation companies, research institutions, and government departments worldwide.

[0003] However, the optimal design of electric vertical takeoff and landing (VTOL) aircraft is a multidisciplinary problem involving aerodynamics, operational control, propulsion systems, and energy management. In particular, the propulsion system, including electric motors, batteries, and propellers (variable-pitch propellers), has a decisive impact on the overall efficiency, range, and safety of the aircraft. VTOL aircraft propulsion systems operate in two significantly different states: vertical takeoff and level flight cruise. The formulation of this flight profile greatly influences the operational control planning and overall efficiency of the motor-variable-pitch propeller system. Furthermore, the adjustable pitch and speed of the variable-pitch propeller provide a wide operating range, while the design of the electric motor limits the operating range of the propeller.

[0004] Traditional aircraft design methods typically involve phased, system-by-system optimization, neglecting the synergistic effects between different systems and disciplines. This approach often leads to local optima rather than overall optimal performance. With the advancement of electric vertical takeoff and landing (EVTOL) technology, optimizing a single system is no longer sufficient to meet design requirements under multi-objective and multi-constraint conditions. Therefore, there is a need to develop a collaborative optimization design method that integrates the profile, operation, and propulsion systems to best account for the significant differences between the wide-speed-range operation characteristics of variable-pitch propellers and the hovering and cruise phases of VTOL aircraft. This approach aims to achieve optimal overall aircraft performance compared to designing the physical systems first and then the operational control systems.

[0005] This patent proposes a collaborative optimization design method for the profile, operation, and propulsion system of an electric vertical takeoff and landing (eVTOL) aircraft. By constructing a multidisciplinary coupled optimization model, it combines the aircraft's profile design, operational performance optimization, and propulsion system design. This design method can simultaneously consider propulsion system design, operational control, and flight profile formulation, taking into account multidisciplinary constraints to achieve optimal overall performance of the aircraft and guide the design and development of eVTOL aircraft. Summary of the Invention

[0006] To address the problem that traditional aircraft design methods neglect the synergy between different systems and disciplines, a joint optimization design method for the profile, operation, and components of electric vertical takeoff and landing (EVTOL) aircraft is proposed, including the following steps:

[0007] Step (1): Design variables include power system design variables d (including motor design torque Q). 电机-设计 Motor design speed ω 电机-设计 propeller diameter d 螺旋桨 Number of battery packs N 电池组 ) and profile design variables p (including climb rate V) 爬升 Cruise speed V 巡航 descent speed V 下降 Cruise altitude h 巡航 Within the design interval, each design variable is randomly generated with an initial value to complete the initialization of the design variables. The dynamic system design variables are substituted into step (2), and the profile design variables are substituted into step (3).

[0008] Step (2): Based on the input power system design variable d and the power system mass calculation model, calculate the power system mass (including the motor mass M). 电机 Battery quality M 电池 Propeller mass M 螺旋桨 ), obtain the takeoff mass MTOM of the aircraft, and substitute it into step (3); the formula for calculating the mass of the power system is as follows:

[0009] Battery quality model:

[0010] M 电池 =N 电池组 ·M 电池组 (14)

[0011] In the formula M 电池组 This refers to the weight of a single battery pack.

[0012] Motor quality model:

[0013]

[0014] In the formula Q 电机-max SQ represents the maximum torque of the motor. 电机 P is the specific torque of the motor. 电机-max SP is the maximum power of the motor. 电机 This refers to the specific power of the motor.

[0015] Propeller mass model:

[0016]

[0017] Aircraft takeoff mass:

[0018] MTOM = M 电池 +M 电机 +M 螺旋桨 +M 空重 (17)

[0019] In the formula M 空重 It is the empty weight of the aircraft (the remaining weight of the aircraft excluding the power system);

[0020] Step (3): Based on the input profile design variable p, the aircraft takeoff mass MTOM, and the aircraft profile demand analysis model, calculate the takeoff thrust T required by the vertical takeoff and landing aircraft. 起飞 Climbing demand thrust T 爬升 Cruise demand thrust T 巡航 The downward demand push T 下降 , landing demand thrust T 降落 Based on the number of propellers N 螺旋桨 Calculate the thrust T required for takeoff of a single variable-pitch propeller. 起飞-螺旋桨 The propeller's climb thrust T 爬升-螺旋桨 Propeller cruise thrust T 巡航-螺旋桨 The propeller's descent requires thrust T 下降-螺旋桨 The propeller landing requires a thrust T 降落-螺旋桨 Substitute this into step (4); the aircraft profile requirement analysis model is as follows:

[0021]

[0022] In the formula, g is the acceleration due to weight, and S ref C is the reference area of ​​the aircraft. D爬升 C is the drag coefficient of the aircraft during climb. D巡航 C is the drag coefficient of the aircraft during cruise. D下降 C is the drag coefficient of the aircraft during descent. L爬升 C is the lift coefficient of the aircraft during climb. L巡航 C is the lift coefficient of the aircraft during cruise. L下降 γ is the lift coefficient of the aircraft during descent. 爬升 γ is the aircraft's climb angle during climb. 下降 This refers to the aircraft's climb angle during descent;

[0023] Step (4): Based on the input thrust requirements of the variable-pitch propeller for takeoff, climb, cruise, descent, and landing, the variable-pitch propeller operating performance model, and the motor operating performance model, calculate the optimal operating point of the motor and propeller under the flight conditions and required thrust for each flight stage of the aircraft, and obtain the operation optimization variable u of the variable-pitch propeller for each flight stage: takeoff speed ω 螺旋桨-起飞Takeoff pitch angle β 螺旋桨-起飞 , Climb speed ω 螺旋桨-爬升 Climb pitch angle β 螺旋桨-爬升 cruising speed ω 螺旋桨-巡航 Cruise pitch angle β 螺旋桨-巡航 Decreasing speed ω 螺旋桨-下降 descent pitch angle β 螺旋桨-下降 , landing speed ω 螺旋桨-降落 Landing pitch angle β 螺旋桨-降落 ;

[0024] Variable-pitch propeller operating performance model:

[0025]

[0026] In the formula, C T C is the propeller lift coefficient. P Let ξ be the propeller power coefficient, and ξ be the dimensionless radial position of each blade element of the propeller. hub Here, c represents the dimensionless radial position of the propeller hub, and N represents the propeller chord length. blades β is the number of propeller blades. ind To induce the incoming flow angle, β ∞ For the free flow angle, C d C is the airfoil drag coefficient. l The lift coefficient of the blade airfoil;

[0027] The free flow angle β of leaf element at position ξ ∞ With induced inflow angle β ind Calculate by solving the following equation:

[0028]

[0029] In the formula, V ∞ The free flow velocity is equal to the aircraft's flight velocity V during flight, ω. 螺旋桨 φ is the propeller speed, φ is the torsion angle, and β is the propeller rotation speed. 螺旋桨 α is the propeller pitch angle, α is the airfoil angle of attack, and C is the propeller pitch angle. lα φ is the lift coefficient when the airfoil angle of attack is α, c is the airfoil chord length, and φ is the lift coefficient. tip The leaf tip twist angle;

[0030] The operating conditions of the propeller are calculated using the following formula:

[0031]

[0032] In the formula, ρ is the air density, and T 螺旋桨 For propeller thrust, ω 螺旋桨 P is the propeller speed. 螺旋桨 Q is the input power to the propeller.螺旋桨 This refers to the propeller torque;

[0033] Motor operating performance model:

[0034]

[0035] In the formula, a Q a is the maximum torque coefficient of the motor. P a is the maximum power coefficient of the motor. ω ω is the maximum speed coefficient of the motor. 电机 Q is the motor speed. 电机 P is the motor torque. 电机-损失 P represents the power loss of the motor. 电机-输出 P is the mechanical work output by the motor. 电机 Q is the electrical power consumed by the motor. 电机-max P is the maximum torque of the motor. 电机-max ω is the maximum output power of the motor. 螺旋桨-max Where C0, C1, C2, and C3 represent the maximum speed of the motor, and C0, C1, C2, and C3 are constants, expressed as follows:

[0036]

[0037] In the formula, 'a' is the fixed loss coefficient, which is η. 电机-设计 Motor design peak efficiency;

[0038] Assuming the motor shaft and propeller shaft are mechanically directly connected, the operating parameters of the motor and propeller satisfy the following relationship:

[0039]

[0040] Step (5): Calculate the constraints based on the input dynamic system design variables, profile design variables and operation optimization variables, and determine whether the design constraints are met. If the constraints are not met, return to step (1) and re-initialize the parameters; if the constraints are met, proceed to step (6).

[0041] The design constraints are as follows:

[0042]

[0043] In the formula C Lmax f is the maximum lift coefficient of the aircraft. M空重 V is the minimum mass fraction of empty weight. 螺旋桨-tip Ma represents the Mach number at the tip of the propeller blade.

[0044] Step (6): Input the power system design variable d, profile design variable p, and operation optimization variable u into the range calculation model to calculate the range R of the vertical take-off and landing aircraft, and use f(d,p,u)=-R as the fitness function of the genetic algorithm;

[0045] The range calculation model is shown below:

[0046]

[0047] In the formula, R is the range of the vertical takeoff and landing aircraft, and t 爬升-0 t is the start time of the climb. 下降-f V is the descent end time, V is the flight speed, γ is the climb angle, and SE is the descent end time. 电池 For the specific energy of the battery, t 起飞-0 For takeoff start time, t 降落-f P is the landing end time. 电池 It consumes power for the battery.

[0048] Step (7): Input the fitness function value f(d,p,u) obtained in step (6) into the genetic algorithm solver, and repeat steps (1) to (6), and input the difference between the two fitness function values ​​into step (8).

[0049] Step (8): If the difference between the fitness function values ​​input in step (7) is greater than the set tolerance ε, repeat step (1) to step (7); if the difference between the fitness function values ​​is less than the set tolerance ε, proceed to step (9).

[0050] Step (9): Optimization complete. Output the optimized design result Opt(d,p,u), completing the joint optimization design of the profile-operation-power system. Attached Figure Description

[0051] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0052] Figure 1 A flowchart illustrating a method for joint optimization design of profile, operation, and power system of an electric vertical takeoff and landing aircraft, provided in an embodiment of this application. Detailed Implementation

[0053] The following is in conjunction with the appendix Figure 1 The present application will be further described in detail through embodiments. The following embodiments are explanations of the present application, but the present application is not limited to the following embodiments.

[0054] Step (1): Design variables include power system design variables d (including motor design torque Q). 电机-设计 Motor design speed ω 电机-设计 propeller diameter d螺旋桨 Number of battery packs N 电池组 ) and profile design variables p (including climb rate V) 爬升 Cruise speed V 巡航 descent speed V 下降 Cruise altitude h 巡航 Within the design interval, each design variable is randomly initialized to complete the initialization of the design variables. The dynamic system design variables are substituted into step (2), and the profile design variables are substituted into step (3). The table below gives the range of values ​​for the design variables used in this implementation case:

[0055] Design variables symbol unit lower boundary upper boundary Motor design torque <![CDATA[Q 电机-设计 ]]> Nm 50 500 Motor design speed <![CDATA[ω 电机-设计 ]]> rpm 500 2000 propeller diameter <![CDATA[d 螺旋桨 ]]> m 2 3 Number of battery packs <![CDATA[N 电池组 ]]> - 2 8 Climb speed <![CDATA[V 爬升 ]]> m / s 50 100 cruising speed <![CDATA[V 巡航 ]]> m / s 50 100 descent speed <![CDATA[V 下降 ]]> m / s 50 100 cruising altitude <![CDATA[h 巡航 ]]> m 1000 5000

[0056] Step (2): Based on the input power system design variable d and the power system mass calculation model, calculate the power system mass (including the motor mass M). 电机 Battery quality M 电池 Propeller mass M 螺旋桨 ), obtain the takeoff mass MTOM of the aircraft, and substitute it into step (3); the formula for calculating the mass of the power system is as follows:

[0057] Battery quality model:

[0058] M 电池 =N 电池组 ·M 电池组 (27)

[0059] In the formula M 电池组 This refers to the weight of a single battery pack.

[0060] Motor quality model:

[0061]

[0062] In the formula Q 电机-max SQ represents the maximum torque of the motor. 电机 P is the specific torque of the motor. 电机-max SP is the maximum power of the motor. 电机 This refers to the specific power of the motor.

[0063] Propeller mass model:

[0064]

[0065] Aircraft takeoff mass:

[0066] MTOM = M 电池 +M 电机 +M 螺旋桨 +M 空重 (30)

[0067] In the formula M 空重This is the empty weight of the aircraft (excluding the remaining weight of the propulsion system); the table below shows the parameter settings for the mass model in this implementation case:

[0068] parameter symbol unit Value Weight of a single battery pack <![CDATA[M 电池组 ]]> kg 35 Motor specific torque <![CDATA[SQ 电机 ]]> Nm / kg 60 Motor specific power <![CDATA[SP 电机 ]]> kW / kg 3 empty weight of aircraft <![CDATA[M 空重 ]]> kg 160kg

[0069] Step (3): Based on the input profile design variable p, the aircraft takeoff mass MTOM, and the aircraft profile demand analysis model, calculate the takeoff thrust T required by the vertical takeoff and landing aircraft. 起飞 Climbing demand thrust T 爬升 Cruise demand thrust T 巡航 The downward demand push T 下降 , landing demand thrust T 降落 Based on the number of propellers N 螺旋桨 Calculate the thrust T required for takeoff of a single variable-pitch propeller. 起飞-螺旋桨 The propeller's climb thrust T 爬升-螺旋桨 Propeller cruise thrust T 巡航-螺旋桨 The propeller's descent requires thrust T 下降-螺旋桨 The propeller landing requires a thrust T 降落-螺旋桨 Substitute this into step (4); the aircraft profile requirement analysis model is as follows:

[0070]

[0071] In the formula, g is the acceleration due to weight, and S ref C is the reference area of ​​the aircraft. D爬升 C is the drag coefficient of the aircraft during climb. D巡航 C is the drag coefficient of the aircraft during cruise. D下降 C is the drag coefficient of the aircraft during descent. L爬升 C is the lift coefficient of the aircraft during climb. L巡航 C is the lift coefficient of the aircraft during cruise. L下降 γ is the lift coefficient of the aircraft during descent. 爬升 γ is the aircraft's climb angle during climb. 下降 The angle of ascent is the aircraft's climb angle during descent; the table below gives the specific parameters of the aircraft profile requirement analysis model in this implementation case:

[0072] parameter symbol unit Value weight acceleration g <![CDATA[kg·m / s 2 ]]> 9.8 aircraft climb angle during climb <![CDATA[γ 爬升 ]]> deg 3 aircraft climb angle during descent <![CDATA[γ 下降 ]]> deg -3 Aircraft reference area <![CDATA[S ref ]]> <![CDATA[m 2 ]]> 2

[0073] Relationship between lift coefficient and drag coefficient:

[0074] Angle of attack -2 0 2 4 6 8 10 12 14 CL 0.335 0.546 0.759 0.971 1.152 1.341 1.491 1.6066 1.687 CD 0.046 0.053 0.0645 0.080 0.098 0.125 0.154 0.1897 0.236

[0075] Step (4): Based on the input thrust requirements of the variable-pitch propeller for takeoff, climb, cruise, descent, and landing, the variable-pitch propeller operating performance model, and the motor operating performance model, calculate the optimal operating point of the motor and propeller under the flight conditions and required thrust for each flight stage of the aircraft, and obtain the operation optimization variable u of the variable-pitch propeller for each flight stage: takeoff speed ω 螺旋桨-起飞 Takeoff pitch angle β 螺旋桨-起飞 , Climb speed ω 螺旋桨-爬升 Climb pitch angle β 螺旋桨-爬升 cruising speed ω 螺旋桨-巡航 Cruise pitch angle β 螺旋桨-巡航 Decreasing speed ω 螺旋桨-下降 descent pitch angle β 螺旋桨-下降 , landing speed ω 螺旋桨-降落 Landing pitch angle β 螺旋桨-降落 ;

[0076] Variable-pitch propeller operating performance model:

[0077]

[0078] In the formula, C T C is the propeller lift coefficient. P Let ξ be the propeller power coefficient, and ξ be the dimensionless radial position of each blade element of the propeller. hub Here, c represents the dimensionless radial position of the propeller hub, and N represents the propeller chord length. blades β is the number of propeller blades. ind To induce the incoming flow angle, β ∞ For the free flow angle, C d C is the airfoil drag coefficient. l The lift coefficient of the blade airfoil;

[0079] The free flow angle β of leaf element at position ξ ∞ With induced inflow angle β ind Calculate by solving the following equation:

[0080]

[0081] In the formula, V ∞ The free flow velocity is equal to the aircraft's flight velocity V during flight, ω. 螺旋桨 φ is the propeller speed, φ is the torsion angle, and β is the propeller rotation speed. 螺旋桨 α is the propeller pitch angle, α is the airfoil angle of attack, and C is the propeller pitch angle. lα φ is the lift coefficient when the airfoil angle of attack is α, c is the airfoil chord length, and φ is the lift coefficient. tip The leaf tip twist angle;

[0082] The operating conditions of the propeller are calculated using the following formula:

[0083]

[0084] In the formula, ρ is the air density, and T 螺旋桨 For propeller thrust, ω 螺旋桨 P is the propeller speed. 螺旋桨 Q is the input power to the propeller. 螺旋桨 This refers to the propeller torque; the table below provides the specific propeller parameters in this implementation case:

[0085]

[0086]

[0087] Motor operating performance model:

[0088]

[0089] In the formula, a Q a is the maximum torque coefficient of the motor. P a is the maximum power coefficient of the motor. ω ω is the maximum speed coefficient of the motor. 电机 Q is the motor speed. 电机 P is the motor torque. 电机-损失 P represents the power loss of the motor. 电机-输出 P is the mechanical work output by the motor. 电机 Q is the electrical power consumed by the motor. 电机-max P is the maximum torque of the motor. 电机-max ω is the maximum output power of the motor. 螺旋桨-max Where C0, C1, C2, and C3 represent the maximum speed of the motor, and C0, C1, C2, and C3 are constants, expressed as follows:

[0090]

[0091] In the formula, 'a' is the fixed loss coefficient, which is η. 电机-设计 The peak efficiency of the motor design; the table below shows the specific parameters of the motor model in this implementation case:

[0092] parameter symbol unit Value Maximum torque coefficient of motor <![CDATA[a Q ]]> - 2 Maximum power coefficient of motor <![CDATA[a P ]]> - 1.8 Maximum speed coefficient of motor <![CDATA[a ω ]]> - 2 Fixed loss coefficient a - 0.95 Motor design peak efficiency <![CDATA[η 电机-设计 ]]> - 0.94

[0093] Assuming the motor shaft and propeller shaft are mechanically directly connected, the operating parameters of the motor and propeller satisfy the following relationship:

[0094]

[0095] Step (5): Calculate the constraints based on the input dynamic system design variables, profile design variables and operation optimization variables, and determine whether the design constraints are met. If the constraints are not met, return to step (1) and re-initialize the parameters; if the constraints are met, proceed to step (6).

[0096] The design constraints are as follows:

[0097]

[0098] In the formula C Lmax f is the maximum lift coefficient of the aircraft. M空重 V is the minimum mass fraction of empty weight. 螺旋桨-tip Ma represents the Mach number at the propeller tip; the table below provides the specific parameters of the design constraints in this implementation case:

[0099] parameter symbol unit Value Maximum lift coefficient of aircraft <![CDATA[C Lmax ]]> - 1.2 Minimum empty weight mass fraction <![CDATA[f M空重 ]]> - 0.4

[0100] Step (6): Input the power system design variable d, profile design variable p, and operation optimization variable u into the range calculation model to calculate the range R of the vertical take-off and landing aircraft, and use f(d,p,u)=-R as the fitness function of the genetic algorithm;

[0101] The range calculation model is shown below:

[0102]

[0103] In the formula, R is the range of the vertical takeoff and landing aircraft, and t 爬升-0 t is the start time of the climb. 下降-f V is the descent end time, V is the flight speed, γ is the climb angle, and SE is the descent end time. 电池 For the specific energy of the battery, t 起飞-0 For takeoff start time, t 降落-f P is the landing end time. 电池 It consumes power for the battery.

[0104] Step (7): Input the fitness function value f(d,p,u) obtained in step (6) into the genetic algorithm solver, and repeat steps (1) to (6), and input the difference between the two fitness function values ​​into step (8).

[0105] Step (8): If the difference between the fitness function values ​​input in step (7) is greater than the set tolerance ε, repeat step (1) to step (7); if the difference between the fitness function values ​​is less than the set tolerance ε, proceed to step (9).

[0106] Step (9): Optimization complete. Output the optimized design result Opt(d,p,u), completing the joint optimization design of the profile-operation-dynamic system. The specific design results are as follows:

[0107]

[0108]

Claims

1. A method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft, characterized in that, Includes the following steps: Step (1): Design variables include power system design variables d (including motor design torque Q). 电机-设计 Motor design speed ω 电机-设计 propeller diameter d 螺旋桨 Number of battery packs N 电池组 ) and profile design variables p (including climb rate V) 爬升 Cruise speed V 巡航 descent speed V 下降 Cruise altitude h 巡航 Within the design interval, each design variable is randomly generated with an initial value to complete the initialization of the design variables. The dynamic system design variables are substituted into step (2), and the profile design variables are substituted into step (3). Step (2): Based on the input power system design variable d and the power system mass calculation model, calculate the power system mass (including the motor mass M). 电机 Battery quality M 电池 Propeller mass M 螺旋桨 ), obtain the takeoff mass MTOM of the aircraft, and input it into step (3); Step (3): Based on the input profile design variable p, the aircraft takeoff mass MTOM, and the aircraft profile demand analysis model, calculate the takeoff thrust T required by the vertical takeoff and landing aircraft. 起飞 Climbing demand thrust T 爬升 Cruise demand thrust T 巡航 The downward demand push T 下降 , landing demand thrust T 降落 Based on the number of propellers N 螺旋桨 Calculate the thrust T required for takeoff of a single variable-pitch propeller. 起飞-螺旋桨 The propeller's climb thrust T 爬升-螺旋桨 Propeller cruise thrust T 巡航-螺旋桨 The propeller's descent requires thrust T 下降-螺旋桨 The propeller landing requires a thrust T 降落-螺旋桨 Substitute this into step (4); Step (4): Based on the input thrust requirements of the variable-pitch propeller for takeoff, climb, cruise, descent, and landing, the variable-pitch propeller operating performance model, and the motor operating performance model, calculate the optimal operating point of the motor and propeller under the flight conditions and required thrust for each flight stage of the aircraft, and obtain the operation optimization variable u of the variable-pitch propeller for each flight stage: takeoff speed ω 螺旋桨-起飞 Takeoff pitch angle β 螺旋桨-起飞 Climb speed ω 螺旋桨-爬升 Climb pitch angle β 螺旋桨-爬升 Cruise speed ω 螺旋桨-巡航 Cruise pitch angle β 螺旋桨-巡航 Decreasing speed ω 螺旋桨-下降 descent pitch angle β 螺旋桨-下降 , landing speed ω 螺旋桨-降落 Landing pitch angle β 螺旋桨-降落 ; Step (5): Calculate the constraints based on the input dynamic system design variables, profile design variables and operation optimization variables, and determine whether the design constraints are met. If the constraints are not met, return to step (1) and re-initialize the parameters; if the constraints are met, proceed to step (6). Step (6): Input the power system design variable d, profile design variable p, and operation optimization variable u into the range calculation model to calculate the range R of the vertical take-off and landing aircraft, and use f(d,p,u)=-R as the fitness function of the genetic algorithm; Step (7): Input the fitness function value f(d,p,u) obtained in step (6) into the genetic algorithm solver, and repeat steps (1) to (6), and input the difference between the two fitness function values ​​into step (8); Step (8): If the difference between the fitness function values ​​input in step (7) is greater than the set tolerance ε, repeat step (1) to step (7); if the difference between the fitness function values ​​is less than the set tolerance ε, proceed to step (9). Step (9): Optimization complete. Output the optimized design result Opt(d,p,u), completing the joint optimization design of the profile-operation-power system.

2. The method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft according to claim 1, characterized in that... The dynamic system mass calculation model described in step (2) is as follows: Battery quality model: M 电池 =N 电池组 ·M 电池组 (1) In the formula M 电池组 This refers to the weight of a single battery pack. Motor quality model: In the formula Q 电机-max SQ represents the maximum torque of the motor. 电机 P is the specific torque of the motor. 电机-max SP is the maximum power of the motor. 电机 This refers to the specific power of the motor. Propeller mass model: Aircraft takeoff mass: MTOM=M 电池 +M 电机 +M 螺旋桨 +M 空重 (4) In the formula M 空重 It is the empty weight of the aircraft (the remaining weight of the aircraft excluding the power system).

3. The method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft according to claim 1, characterized in that... The aircraft profile requirement analysis model described in step (3) is shown below: In the formula, g is the acceleration due to weight, and S ref C is the reference area of ​​the aircraft. D爬升 C is the drag coefficient of the aircraft during climb. D巡航 C is the drag coefficient of the aircraft during cruise. D下降 C is the drag coefficient of the aircraft during descent. L爬升 C is the lift coefficient of the aircraft during climb. L巡航 C is the lift coefficient of the aircraft during cruise. L下降 γ is the lift coefficient of the aircraft during descent. 爬升 γ is the aircraft's climb angle during climb. 下降 This is the aircraft's climb angle during descent.

4. The method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft according to claim 1, characterized in that... The variable-pitch propeller performance model and the motor performance model mentioned in step (4) are shown below: Variable-pitch propeller operating performance model: In the formula, C T C is the propeller lift coefficient. P Let ξ be the propeller power coefficient, and ξ be the dimensionless radial position of each blade element of the propeller. hub Here, c represents the dimensionless radial position of the propeller hub, and N represents the propeller chord length. blades β is the number of propeller blades. ind To induce the incoming flow angle, β ∞ For the free flow angle, C d C is the airfoil drag coefficient. l The lift coefficient of the blade airfoil; The free flow angle β of leaf element at position ξ ∞ With induced inflow angle β ind Calculate by solving the following equation: In the formula, V ∞ The free flow velocity is equal to the aircraft's flight velocity V during flight, ω. 螺旋桨 φ is the propeller speed, φ is the torsion angle, and β is the propeller rotation speed. 螺旋桨 α is the propeller pitch angle, α is the airfoil angle of attack, and C is the propeller pitch angle. lα φ is the lift coefficient when the airfoil angle of attack is α, c is the airfoil chord length, and φ is the lift coefficient. tip The leaf tip twist angle; The operating conditions of the propeller are calculated using the following formula: In the formula, ρ is the air density, and T 螺旋桨 For propeller thrust, ω 螺旋桨 P is the propeller speed. 螺旋桨 Q is the input power to the propeller. 螺旋桨 This refers to the propeller torque; Motor operating performance model: In the formula, a Q a is the maximum torque coefficient of the motor. P a is the maximum power coefficient of the motor. ω ω is the maximum speed coefficient of the motor. 电机 Q is the motor speed. 电机 P is the motor torque. 电机-损失 P represents the power loss of the motor. 电机-输出 P is the mechanical work output by the motor. 电机 Q is the electrical power consumed by the motor. 电机-max P is the maximum torque of the motor. 电机-max ω is the maximum output power of the motor. 螺旋桨-max Where C0, C1, C2, and C3 represent the maximum speed of the motor, and C0, C1, C2, and C3 are constants, expressed as follows: In the formula, 'a' is the fixed loss coefficient, which is η. 电机-设计 Motor design peak efficiency; Assuming the motor shaft and propeller shaft are mechanically directly connected, the operating parameters of the motor and propeller satisfy the following relationship:

5. The method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft according to claim 1, characterized in that... The design constraints described in step (5) are as follows: In the formula C Lmax f is the maximum lift coefficient of the aircraft. M空重 V is the minimum mass fraction of empty weight. 螺旋桨-tip Ma represents the Mach number at the tip of the propeller blade.

6. The method for joint optimization design of profile, operation, and components of an electric vertical takeoff and landing aircraft according to claim 1, characterized in that... The range calculation model described in step (6) is as follows: In the formula, R is the range of the vertical takeoff and landing aircraft, and t 爬升-0 t is the start time of the climb. 下降-f V is the descent end time, V is the flight speed, γ is the climb angle, and SE is the descent end time. 电池 For the specific energy of the battery, t 起飞-0 For takeoff start time, t 降落-f P is the landing end time. 电池 It consumes power for the battery.

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