An engine supercharging system for an unmanned aerial vehicle and its control method

Abstract

The present invention provides a supercharging system for an unmanned aerial vehicle (UAV) engine and its control method, which relates to the technical field of UAV engines. It includes a drive adjustment mechanism, a sensor module, a control module, a rotary motor, and a turbine motor. Among them, the drive adjustment mechanism drives a slider to move through a lead screw, and the slider pushes an eccentric wheel to drive the blade to rotate, realizing synchronous adjustment of the pitch of multiple blades; the sensor module collects the engine speed, ambient air pressure, and engine intake air temperature in real time, and the control module calculates the target pitch and target turbine speed based on conditional equations, and realizes closed-loop control through coordinated driving of the motors. The present invention proposes an adjustment strategy that combines database look-up and load mutation response mechanism, and introduces tolerance control logic to improve system stability. Compared with traditional mechanical supercharging schemes, this system has the advantages of light weight, rapid response, strong plateau adaptability, high energy efficiency ratio, etc., and is suitable for UAV flight missions with long endurance and in complex environments of various types.

Description

Technical Field

[0001] The present invention relates to the technical field of UAV engines, and particularly to a supercharging system for a UAV engine and a control method thereof. Background Art

[0002] In recent years, UAVs have been widely used in tasks such as surveying and mapping, cruising, environmental monitoring, and disaster warning. Especially in complex environments such as plateaus, high altitudes, and oceans, higher requirements are placed on the power systems of UAVs. The intake efficiency of traditional naturally aspirated piston engines drops significantly when the air density decreases. As the flight altitude increases, its power output decays substantially.

[0003] Although turbojet engines have the ability to adapt to plateaus, their fuel consumption is high and the endurance time is short, which is not suitable for long-duration and low-cost mission scenarios. In contrast, piston-type turbocharged engines are widely used in long-endurance UAV missions due to their good fuel economy and compact structure, such as in border patrol, geological exploration, and marine monitoring fields. Optimizing their performance has important application value.

[0004] Existing piston supercharging systems mostly use exhaust gas turbines to drive, and a complex cooling system needs to be designed to cool the high-temperature exhaust gas. At the same time, exhaust gas turbines need to use high heat-resistant alloy materials, with complex structures and high manufacturing costs. In addition, the exhaust gas turbine has a "turbo lag" problem under low-speed working conditions, resulting in delayed acceleration response and poor system stability. For this reason, some solutions introduce an electronic turbocharger to assist in intake. It can work under normal temperature conditions, avoiding the need for high-temperature resistant materials and cooling structures, and the electronic turbocharger has a faster response at low speeds, which is beneficial to achieving linear supercharging adjustment. However, existing electronic turbocharger-assisted intake systems still face certain technical challenges in terms of compact design, flexible control ability of blade angle adjustment, and dynamic response coordination between intake parameters and changes in the flight environment, and it is still difficult to fully meet the continuous power output and efficient adjustment requirements of UAVs in plateau, variable load, and multi-condition missions. Summary of the Invention

[0005] In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a supercharging system for a UAV engine, adopting the following technical solutions:

[0006] A supercharging system for a UAV engine, comprising:

[0007] The drive adjustment mechanism includes a fixed seat disposed at the air inlet of the supercharger. A slider is provided inside the fixed seat, and a lead screw for driving the slider to move back and forth along the axial direction of the fixed seat. An installation cavity is circumferentially provided between the fixed seat and the slider, and a plurality of installation holes are provided at corresponding positions of the fixed seat in the installation cavity. The fixed shaft of the blade is rotatably disposed in the installation hole, and an eccentric wheel is provided in the installation cavity. When the slider moves, it pushes the outer edge of the eccentric wheel to rotate the blade, thereby changing the pitch between adjacent blades;

[0008] The sensor module includes a rotational speed sensor, a barometric pressure sensor, and a temperature sensor, which are respectively used to monitor the engine speed R, the ambient air pressure P, and the engine intake air temperature T;

[0009] The control module is electrically connected to the sensor module, generates a target pitch L tgt and a target turbine speed n tgt , and outputs a control signal to control the rotation of the lead screw through a rotary motor to adjust the pitch between adjacent blades, and controls the rotation of the fixed seat through a turbine to adjust the turbine speed;

[0010] The above target pitch L tgt and the target turbine speed n tgt satisfy the following conditional formula:

[0011] n tgt ·L tgt =f·T·R / P;

[0012] where f is a preset proportionality constant, R is the engine speed, T is the engine intake air temperature, and P is the ambient air pressure;

[0013] Based on the above conditional formula n tgt ·L tgt =f·T·R / P, multiple groups of parameter combinations that meet the conditions are generated, and a target parameter combination is selected from the multiple groups of parameter combinations. The selection methods include:

[0014] In the energy-saving mode, call the pre-stored power consumption database and select the target pitch L tgt with the lowest power consumption and the target turbine speed n tgt parameter combination;

[0015] When the load suddenly changes, keep the target turbine speed n tgt constant and adjust the target pitch L tgt to achieve a quick response;

[0016] The above preset proportionality constant f is defined by the following parameter combination:

[0017] f = P0·b / (T0·a);

[0018] Among them, T0 is 20°C, P0 is the atmospheric pressure at 20°C, a is a combined fixed value of the efficiency of the intake system and mechanical structure parameters, and b is a combined fixed value of the volumetric efficiency of the engine displacement.

[0019] For further improvement, the above-mentioned target turbine speed n tgt has an adjustment range of 1000 rps to 6000 rps. Sampling points are selected at intervals of 500 rps, the pitch corresponding to the corresponding speed is calculated, and the lowest power point of each sampling point is recorded to generate the above-mentioned power consumption database.

[0020] For further improvement, the rotation angle α of the above-mentioned blade ranges from 0 to 60°, and the above-mentioned target pitch L tgt is mapped to the rotation angle α of the above-mentioned blade through the function L = g(α), and the above-mentioned control module calculates the rotation angle α according to the target pitch L tgt

[0021] For further improvement, a sliding groove is provided inside the above-mentioned fixed seat, the above-mentioned slider moves back and forth in the above-mentioned sliding groove, a receiving groove is provided on the outside of the above-mentioned slider, and the above-mentioned sliding groove and the receiving groove enclose the above-mentioned installation cavity; when the above-mentioned slider slides outwards, the inner side wall of the above-mentioned receiving groove pushes the outer edge of the above-mentioned eccentric wheel outwards, and the rotation angle α of the above-mentioned blade increases and the pitch increases; when the above-mentioned slider slides inwards, the outer side wall of the above-mentioned receiving groove pushes the outer edge of the above-mentioned eccentric wheel inwards, and the rotation angle α of the above-mentioned blade decreases and the pitch shortens.

[0022] For further improvement, the outer edge of the above-mentioned eccentric wheel abuts against the upper and lower end faces of the above-mentioned receiving groove respectively.

[0023] For further improvement, the above-mentioned fixed seat is provided with a guiding groove, the above-mentioned slider is provided with a guiding member, and the above-mentioned guiding member passes through the above-mentioned guiding groove to prevent the above-mentioned slider from rotating.

[0024] A control method for a drone engine supercharging system, which is applied to the drone engine supercharging system proposed in any one of the above, includes the following steps:

[0025] S1: The engine speed R, the ambient pressure P, and the engine intake temperature T are obtained in real time through a speed sensor, a pressure sensor, and a temperature sensor;

[0026] S2: Based on the conditional formula n tgt ·L tgt = f·T·R / P, multiple groups of parameter combinations of the target pitch L tgt and the target turbine speed n tgt that meet the conditions are obtained;

[0027] ​S3: Call the pre-stored power consumption database and select the target pitch L with the lowest power consumption tgt and the target turbine speed n tgt Parameter combination;

[0028] S4: The control module drives the rotary motor to move the slider, adjusts the rotation angle α of the blades through the function L= g(α), and further adjusts the pitch between adjacent blades; drives the turbine motor to adjust the turbine speed;

[0029] S5: The control module dynamically calculates the target value V based on the real-time collected engine speed R, ambient air pressure P and engine intake temperature T tgt =f·T·R / P, and the real-time n tgt ·L tgt With the target value V tgt Compare, if the error | n tgt ·L tgt -V tgt ∣If the set tolerance is exceeded, the target pitch L is corrected tgt and the target turbine speed n tgt .

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] First, the present invention forms a driving and adjusting mechanism consisting of a fixed seat, a slider, a screw and an eccentric wheel, forming a structural link in which the slider pushes the eccentric wheel, the eccentric wheel drives the blades to rotate, and then the pitch is changed in a linked manner, thereby realizing synchronous adjustment of the pitch between multiple blades. The structural design is compact, the movement path is short, and the linkage response is rapid. The axial displacement of the eccentric wheel is effectively limited by the cooperation of the slider, the sliding groove and the receiving groove, thereby ensuring the stability and consistency of the blade rotation. It is suitable for UAV engine supercharging systems with limited space and high requirements for response speed. On the premise of ensuring structural reliability, the volume and weight of the supercharging system are reduced, and the overall applicability and environmental adaptability are improved. It is particularly suitable for complex flight scenarios such as plateaus, low temperatures, and low pressures.

[0032] Secondly, the present invention obtains the engine speed R, the ambient air pressure P and the engine intake temperature T in real time through the sensor module, and the control module is based on the conditional formula n tgt ·L tgt =f·T·R / P Dynamically generate target pitch L tgt and the target turbine speed n tgt, an adaptive intelligent control logic centered on the intake condition is constructed. The system provided by the present invention not only supports preferentially selecting the parameter combination with the lowest power consumption through the look-up table method in the energy-saving mode, but also can keep the turbine speed unchanged when the load suddenly changes, and only adjust the pitch to respond quickly to ensure stable intake. Further, the target function mapping L = g(α) is introduced to convert the target pitch into the rotation angle α of the blade, and the slider is driven by the rotating motor to displace as required, realizing the continuity and accuracy of angle control, and greatly improving the fine adjustment ability of the engine intake air volume in the dynamic flight state.

[0033] Thirdly, the present invention introduces a closed-loop feedback mechanism in the control module to compare the target formula value V tgt = f·T·R / P with the product n tgt ·L tgt of the actual turbine parameters in real time, and sets a tolerance to allow errors within a certain range. Only when the tolerance interval is exceeded, the adjustment action is triggered, effectively avoiding the problem of frequent system adjustment caused by small perturbations. This tolerance control strategy improves the stability and anti-interference ability of the system operation, reduces the start-stop frequency of the rotating motor and the turbine motor, prolongs the life of key components, and reduces energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is a schematic diagram of the frame connection of the system in the present invention;

[0036] Figure 2 It is an assembly schematic diagram of the supercharger in the present invention;

[0037] Figure 3 It is a schematic diagram of the structure of the drive adjustment mechanism in the present invention;

[0038] Figure 4 It is an exploded structure schematic diagram of an embodiment of the drive adjustment mechanism in the present invention;

[0039] Figure 5 It is an assembly structure schematic diagram of the fixed seat in the present invention;

[0040] Figure 6 It is a schematic diagram of the structure of the blade in the present invention;

[0041] Figure 7 It is a step flow chart of the control method in the present invention.

[0042] Reference numerals:

[0043] 1 - drive adjustment mechanism; 2 - sensor module; 3 - control module; 4 - turbine motor; 5 - housing;

[0044] 11 - fixed seat; 11a - upper cover; 11b - base; 12 - slider; 13 - lead screw; 14 - blade; 15 - rotary motor;

[0045] 11a - upper cover; 11b - base; 11a1 - second notch; 11b1 - first notch; 111 - mounting hole; 112 - sliding groove; 113 - guiding groove; 114 - mating surface; 121 - receiving groove; 122 - guiding member; 141 - fixed shaft; 142 - eccentric wheel; 143 - limiting platform;

[0046] 21 - rotational speed sensor; 22 - air pressure sensor; 23 - temperature sensor;

[0047] 41 - stator; 42 - rotor;

[0048] 51 - mounting bracket;

[0049] 100 - supercharger. Detailed implementation manner

[0050] For the convenience of those skilled in the art to understand, the structure of the present invention will now be further described in detail with reference to the accompanying drawings in the embodiments:

[0051] In the description of the present invention. The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. The terms "part", "side", "end", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present invention.

[0052] On the one hand, the present invention provides a supercharging system for an unmanned aerial vehicle engine, as Figure 1 shown, including a drive adjustment mechanism 1, a sensor module 2 and a control module 3. As Figure 2 shown in the piston - type turbocharged engine, a supercharger 100 is provided at the air inlet. The drive adjustment mechanism 1 includes a fixed seat 11 provided at the air inlet of the supercharger 100, as Figure 3As shown, a slider 12 is arranged in the fixed seat 11, and a screw 13 that drives the slider 12 to move back and forth along the axial direction of the fixed seat 11, a mounting cavity is arranged around the fixed seat 11 and the slider 12, and the fixed seat 11 is provided with a plurality of mounting holes 111 at corresponding positions of the mounting cavity, a fixed shaft 141 of the blade 14 is rotatably arranged in the mounting hole 111, and an eccentric wheel 142 is arranged in the mounting cavity, when the slider 12 moves, it pushes the outer edge of the eccentric wheel 142 to rotate the blade 14, thereby changing the pitch between adjacent blades 14.

[0053] Through the above design, the pitch of the blade 14 can be precisely adjusted, and the adaptability of the supercharger 100 under different flight altitudes and load changes can be improved. In particular, the air intake volume is increased at high altitudes, the power output of the engine is optimized, the power loss can be effectively reduced, and the continuous flight capability and stability of the UAV aircraft can be improved.

[0054] In a specific embodiment, Figures 1 - 3 As shown, the driving and adjusting mechanism 1 is arranged at the air inlet of the supercharger 100, and the fixing seat 11 is used to fix the blades, and the outer contour is a cylinder, and the blades are arranged around the side of the cylinder. The fixing seat 11 is hollow inside and is sleeved with the above-mentioned slider 12. A sliding groove 112 is opened inside the fixing seat 11, and the slider 12 moves back and forth in the sliding groove 112. For ease of understanding, the air inlet direction of the air inlet is defined as from outside to inside. The slider 12 can slide inward or outward inside the fixing seat 11, and the sliding area is limited to the sliding groove 112.

[0055] In the above embodiment, if Figure 3 and Figure 4 As shown, the housing 5 is also included. The housing 5 is fixed to the engine body, and a mounting bracket 51 is arranged inside the housing. The mounting bracket 51 is fixed with a rotating motor 15 and a turbine motor 4. The output end of the rotating motor 15 is connected to the screw rod 13, and the output end of the turbine motor 4 is connected to the fixing seat 11, which is used to drive the fixing seat 11 to rotate, that is, drive the blades 14 to rotate and enter the wind. As a preferred embodiment, Figure 3 As shown, a mounting bracket 51 is provided at the lower side of the housing 5, and the rotating motor 15 and the turbine motor 4 are fixedly mounted on the mounting bracket 51 in sequence. More specifically, the turbine motor 4 is a brushless motor, including a stator 41 and a rotor 42. The stator 41 is fixedly mounted on the upper surface of the rotating motor 15 body to drive the rotor 42 to rotate. Furthermore, the middle parts of the stator 41 and the rotor 42 are hollowed out to form a clearance channel for allowing the screw rod 13 to pass through. The screw rod 13 passes through the hollowed-out middle area of the rotor 42 and the stator 41 and is connected to the output end of the rotating motor 15. The above-mentioned fixing seat 11 is fixedly mounted on the rotor 42. This structure realizes the combined assembly of the rotating motor 15 and the turbine motor 4, realizes the separate control of the speed adjustment and the pitch adjustment of the blade 14, and also significantly reduces the internal space of the supercharger 100.

[0056] As shown in Figure 3 and Figure 4 As shown, a receiving groove 121 is formed on the outer side of the slider 12, and the sliding groove 112 and the receiving groove 121 enclose to form the above-mentioned installation cavity. When the slider 12 slides outwards, the inner side wall of the receiving groove 121 pushes the outer edge of the eccentric wheel 142 outwards, increasing the rotation angle α of the paddle 14 and increasing the pitch; when the slider 12 slides inwards, the outer side wall of the receiving groove 121 pushes the outer edge of the eccentric wheel 142 inwards, decreasing the rotation angle α of the paddle 14 and shortening the pitch. Preferably, the inner and outer sides of the outer edge of the eccentric wheel 142 are respectively abutted against the inner plate and the outer plate of the receiving groove 121.

[0057] As shown in Figure 3 and Figure 4 As shown, the lead screw 13 is arranged at the centers of the fixed seat 11 and the slider 12. The slider 12 is threadedly connected to the lead screw 13. The fixed seat 11 is provided with a guiding groove 113, and the slider 12 is provided with a guiding member 122. The guiding member 122 passes through the guiding groove 113. This structure is also used to prevent the slider 12 from rotating. Preferably, the guiding grooves 113 are arranged on both the top plate and the bottom plate of the fixed seat 11 along the air inlet direction. Correspondingly, the guiding members 122 are arranged at the top and bottom of the slider 12. The guiding grooves 113 and the guiding members 122 are in the shape of a rectangle or other polygons, which can not only enable the slider 12 to slide along the guiding groove 113, but also limit its rotation around the lead screw 13.

[0058] As shown in Figure 5 As shown, a plurality of fitting surfaces 114 are arranged on the inner side wall of the fixed seat 11, and the eccentric wheel 142 of the paddle 14 fits or abuts against the fitting surfaces 114 to enable it to rotate more smoothly.

[0059] As shown in Figure 4 and Figure 5 As shown, in one embodiment, the fixed seat 11 is composed of a base 11b and an upper cover 11a. The base 11b is provided with a first notch 11b1, and the upper cover 11a is correspondingly provided with a second notch 11a1. When the upper cover 11a covers the base 11b, the first notch 11b1 and the second notch 11a1 fit together to form the above-mentioned installation hole 111. During installation, the slider 12 is placed in the base 11b, the paddle 14 is sequentially placed along the first notch 11b1 of the base 11b, and then the upper cover 11a is covered to complete the assembly of the fixed seat 11, the slider 12 and the paddle 14.

[0060] As shown in Figure 4 and Figure 5As shown in the figure, in one embodiment, ten fitting surfaces 114 are provided on the inner side wall of the sliding groove 112 at equal lengths. Preferably, the fitting surface 114 is a plane, that is, the inner contour of the fixed seat 11 in the front view is a regular decagon. A mounting hole 111 is correspondingly provided on each fitting surface 114. More specifically, both the base 11b and the upper cover 11a are provided with ten fitting surfaces 114. The base 11b is correspondingly provided with a first notch 11b1 on each fitting surface 114. Similarly, the upper cover 11a is correspondingly provided with a second notch 11a1 on each fitting surface 114. A total of ten blades 14 are installed in this embodiment. During installation, the eccentric wheel 142 fits on the fitting surfaces 114 of the base 11b and the upper cover 11a.

[0061] Further, as Figures 3 - 6 shown, a limiting platform 143 is provided on the side of the fixed shaft 141 away from the eccentric wheel 142. The limiting platform 143 and the eccentric wheel 142 respectively abut against the inner and outer sides of the mounting hole 111. In the above embodiment, the fixed shaft 141 of the blade 14 is placed in the first notch 11b1 of the base 11b, and the limiting platform 143 and the eccentric wheel 142 respectively abut against the inner and outer sides of the first notch 11b1 to form a pre-installation. Preferably, a fitting surface 114 corresponding to the inner side surface is provided on the outer side of the fixed seat 11. The outer fitting surface 114 is used to fit the limiting platform 143, and its function is also to make the rotation of the blade 14 smoother and more fluent.

[0062] As Figure 1 shown, the system further includes a sensor module 2. Specifically, it includes a rotational speed sensor 21, an air pressure sensor 22, and a temperature sensor 23, which are respectively used to monitor the engine rotational speed R, the ambient air pressure P, and the engine intake air temperature T. It also includes a control module 3, which is electrically connected to the sensor module 2, generates a target pitch L tgt and a target turbine rotational speed n tgt , and outputs a control signal to control the rotation of the lead screw 13 through the rotary motor 15, adjust the pitch between adjacent blades 14, and adjust the turbine rotational speed through the turbine motor 4. It should be noted and understood uniformly that the parallel distance between adjacent blades 14 is the above-mentioned pitch. When the deflection angle of the blade 14 increases, the pitch increases. When the deflection angle of the blade 14 decreases, the pitch decreases. When the blade 14 (under permitted conditions) is perpendicular to the intake direction, the pitch is zero.

[0063] Further, the target pitch L tgt and the target turbine rotational speed n tgt satisfy the following conditional formula:

[0064] n tgt ·L tgt =f·T·R / P;

[0065] Among them, f is a preset proportional constant, R is the engine speed, T is the engine intake air temperature, and P is the ambient air pressure.

[0066] Based on the conditional formula n tgt ·L tgt = f·T·R / P, generate multiple groups of parameter combinations that meet the conditions, and select the target parameter combination from the multiple groups of parameter combinations. The selection methods include:

[0067] In the energy-saving mode, call the pre-stored power consumption database, and select the target pitch L with the lowest power consumption by looking up the table tgt and the target turbine speed n tgt parameter combination;

[0068] When the load suddenly changes, keep the target turbine speed n tgt constant, and adjust the target pitch L tgt to achieve a fast response.

[0069] The specific derivation of the above conditional formula is as follows:

[0070] Calculate the intake air volume Q of the supercharger 100 IN :

[0071] Q IN = η M ·k·n·L·ρ·f(Re, …);

[0072] Among them, η M is the mechanical efficiency, dimensionless, and its value range is between 0 and 1; k is the proportional constant reflecting the geometric structure of the reaction fan or pump; n is the turbine speed; L is the pitch of the blade 14; ρ is the intake air density; f(Re, …) represents the function related to hydrodynamics, including but not limited to other relevant fluid characteristics such as Reynolds number Re, density, and viscosity. The above mechanical efficiency η M 、proportional constant k and function f(Re, …) are constants that can be measured from experimental data over time. To simplify the calculation, introduce the combined fixed value a = η M ·k·f(Re, …), which reflects the efficiency of the intake system and the mechanical structure parameters. Then the intake air volume Q of the supercharger 100 IN = a·n·L·ρ;

[0073] Calculate the gas consumption Q of the internal combustion engine EXP :

[0074] Q EXP = η V ·ρ·V·R / 2;

[0075] Among them, η Vis the volumetric efficiency, dimensionless, with a value range between 0 and 1; ρ is the intake air density; V is the engine displacement; R is the engine speed. The above volumetric efficiency η V and the engine displacement V are constants that can be measured from time experimental data. Introduce the combined fixed value b = η V ·V / 2, which reflects the volumetric efficiency of the engine displacement, then the air consumption Q EXP = b·ρ·R.

[0076] To enable the drone to achieve the same intake air volume at high altitude as in the case of zero altitude, normal temperature (20°C), and air density ρ0, that is

[0077] a·n·L·ρ = Q IN = Q EXP0 = b·ρ0·R;

[0078] After arrangement, we get: n·L = b·ρ0·R / a·ρ;

[0079] Among them, ρ0 = P0 / (S·T0), ρ = P / (S·T), S is the gas constant of air (unit: J / (kg·K), approximately 287 J / (kg·K)), P is the atmospheric pressure, and T is the engine intake temperature.

[0080] That is, we get n·L = b·P0·T·R / (a·P·T0). Introduce the preset proportional constant

[0081] f = P0·b / (T0·a);

[0082] Among them, T0 is 20°C, and P0 is the atmospheric pressure at 20°C;

[0083] We get n·L = f·T·R / P, that is, the target pitch L tgt and the target turbine speed n tgt satisfy: n tgt ·L tgt = f·T·R / P.

[0084] As an embodiment, the adjustment range of the target turbine speed n tgt is 1000 rps to 6000 rps. Sampling points are selected at intervals of 500 rps, the pitch corresponding to the corresponding speed is calculated, and the lowest power point at each sampling point is recorded to generate a power consumption database.

[0085] As an embodiment, the rotation angle α of the blade 14 ranges from 0 to 60°. The target pitch L tgt and the rotation angle α of the blade 14 are mapped through the function L = g(α), and the control module 3 calculates the rotation angle α according to the target pitch L tgt

[0086] ​The present invention further provides a control method for a supercharging system of a drone engine, which is applied to the above-mentioned drone engine supercharging system, as Figure 7 shown, and includes the following steps:

[0087] S1: Through the rotational speed sensor 21, the air pressure sensor 22, and the temperature sensor 23, the engine rotational speed R, the ambient air pressure P, and the engine intake air temperature T are obtained in real time;

[0088] S2: Based on the conditional formula n·L = f·T·R / P, the target pitch L tgt and the target turbine rotational speed n tgt of multiple groups of parameter combinations are obtained;

[0089] S3: Call the pre-stored power consumption database, and select the target pitch L with the lowest power consumption tgt and the target turbine rotational speed n tgt parameter combination;

[0090] S4: The control module 3 drives the rotary motor 15 to move the slider 12, adjusts the rotation angle α of the blade 14 through the function L = g(α), and further adjusts the pitch between adjacent blades 14; drives the turbine motor 4 to adjust the turbine rotational speed;

[0091] S5: The control module 3 dynamically calculates the target value V target = f·T·R / P based on the engine rotational speed R, the ambient air pressure P, and the engine intake air temperature T collected in real time, and compares the real-time n·L with the target value V target If the error ∣n·L - V target ∣ exceeds the set tolerance, then the target pitch L tgt and the target turbine rotational speed n tgt are corrected.

[0092] In step S3, if a load mutation occurs, the target turbine rotational speed n tgt is kept unchanged, and the target pitch L tgt is adjusted to satisfy the conditional formula n tgt ·L tgt = f·T·R / P.

[0093] Load mutation situations such as when the drone suddenly encounters strong winds or makes an emergency climb / dive, resulting in a sudden increase or decrease in the engine thrust requirement, or when the blade 14 encounters a sudden change in resistance due to wave impact or emergency turning. In a specific embodiment, when the drone in cruise suddenly encounters a vertical gust of wind, resulting in a sudden increase in the fuselage elevation angle, the engine instantaneously increases the thrust to maintain altitude. During this process, the air pressure sensor 22 detects a decrease in the ambient air pressure, and the control module 3 keeps the set target turbine rotational speed n tgt unchanged and immediately increases the pitch L tgt so that n tgt ·L tgt=f·T·R / P, rapid thrust recovery. When the vehicle leaves the wind area or the gust ends, the system detects that the product of the turbine speed n and the pitch L is higher than the tolerance, that is, |n·LV target | If the set tolerance is exceeded, the control module 3 gradually reduces the pitch L and returns to the parameter combination with the lowest power consumption by looking up the table.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An unmanned aerial vehicle engine supercharging system, characterized in that, Comprising: A drive adjustment mechanism (1), including a fixed seat (11) disposed at the air inlet of a supercharger (100), a slider (12) is disposed inside the fixed seat (11), and a lead screw (13) for driving the slider (12) to move back and forth along the axial direction of the fixed seat (11). An installation cavity is circumferentially disposed between the fixed seat (11) and the slider (12), and a plurality of installation holes (111) are disposed at corresponding positions of the fixed seat (11) in the installation cavity. A fixed shaft (141) of a blade (14) of the supercharger (100) is rotatably disposed in the installation holes (111), and an eccentric wheel (142) is disposed in the installation cavity. When the slider (12) moves, the outer edge of the eccentric wheel (142) is pushed, causing the blade (14) to rotate, thereby changing the pitch between adjacent blades (14); A sensor module (2), including a rotational speed sensor (21), a barometric pressure sensor (22), and a temperature sensor (23), which are respectively used to monitor the engine speed R, the ambient air pressure P, and the engine intake air temperature T; A control module (3), electrically connected to the sensor module (2), generates a target pitch L tgt and a target turbine speed n tgt , and outputs a control signal to control the rotation of the lead screw (13) through the rotary motor (15), adjust the pitch between adjacent blades (14), and control the rotation of the fixed seat (11) through the turbine motor (4) to adjust the turbine speed; The target pitch L tgt and the target turbine speed n tgt satisfy the following conditional expression: n tgt ·L tgt = f·T·R / P; Wherein, f is a preset proportionality constant, R is the engine speed, T is the engine intake air temperature, and P is the ambient air pressure; Based on the conditional n tgt ·L tgt = f·T·R / P, generate multiple sets of parameter combinations that meet the conditions, and select a target parameter combination from the multiple sets of parameter combinations. The selection methods include: In the energy-saving mode, a pre-stored power consumption database is called, and the target pitch L with the lowest power consumption is selected by looking up the table. tgt and the target turbine speed n tgt parameter combination; When there is a load mutation, maintain the target turbine speed n tgt constant and adjust the target pitch L tgt to achieve a fast response; The preset proportionality constant f is defined by the following parameter combination: f = P0·b / (T0·a); Wherein, T0 is 20 °C, P0 is the atmospheric pressure at 20 °C, a is a combined fixed value of the efficiency of the intake system and mechanical structure parameters, and b is a combined fixed value of the volumetric efficiency of the engine displacement.

2. The supercharging system for a drone engine according to claim 1, characterized in that, The target turbine speed n tgt has an adjustment range of 1000 rps to 6000 rps. Sampling points are selected at intervals of 500 rps, the pitch at the corresponding speed is calculated, and the lowest power point at each sampling point is recorded to generate the power consumption database.

3. The supercharging system for a drone engine according to claim 2, wherein, The rotation angle α of the paddle blade ranges from 0 to 60°, and the target pitch L tgt is mapped to the rotation angle α of the paddle blade (14) through the function L = g(α). The control module (3) calculates the rotation angle α according to the target pitch L tgt to calculate the rotation angle α.

4. The supercharging system for a drone engine according to claim 1, wherein, A sliding groove (112) is formed inside the fixed seat (11), the slider (12) moves back and forth in the sliding groove (112), a receiving groove (121) is formed on the outer side of the slider (12), and the sliding groove (112) and the receiving groove (121) enclose to form the installation cavity; when the slider (12) slides outwards, the inner side wall of the receiving groove (121) pushes the outer edge of the eccentric wheel (142) outwards, and the rotation angle α of the blade (14) increases and the pitch increases; when the slider (12) slides inwards, the outer side wall of the receiving groove (121) pushes the outer edge of the eccentric wheel (142) inwards, and the rotation angle α of the blade (14) decreases and the pitch shortens.

5. The supercharging system for a drone engine according to claim 4, characterized in that, A limiting platform (143) is disposed on one side of the fixed shaft (141) away from the eccentric wheel (142), and the limiting platform (143) and the eccentric wheel (142) respectively abut against the inner and outer sides of the installation holes (111).

6. The supercharging system for a drone engine according to claim 1, wherein, The fixed seat (11) is provided with a guiding groove (113), the slider (12) is provided with a guiding member (122), and the guiding member (122) passes through the guiding groove (113) to prevent the slider (12) from rotating.

7. A control method for a supercharging system of a drone engine, which is applied to the supercharging system of a drone engine according to any one of claims 1-6, characterized in that, Including the following steps: S1: Through the rotational speed sensor (21), the barometric pressure sensor (22), and the temperature sensor (23), the engine speed R, the ambient air pressure P, and the engine intake air temperature T are obtained in real time; S2: Based on conditional expression n tgt ·L tgt = f·T·R / P to obtain the target pitch L that meets the conditions tgt and the target turbine speed n tgt for multiple groups of parameter combinations; S3: Call the pre-stored power consumption database and select the target pitch L with the lowest power consumption tgt and the target turbine speed n tgt parameter combination; S4: The control module (3) drives the rotary motor (15) to move the slider, adjusts the rotation angle α of the blade (14) through the function L = g(α), and further adjusts the pitch between adjacent blades (14); drives the turbine motor (4) to adjust the turbine speed; S5: The control module dynamically calculates the target value V based on the engine speed R, ambient air pressure P, and engine intake air temperature T collected in real time tgt = f·T·R / P, and compares the real-time n tgt ·L tgt with the target value V tgt If the error ∣n tgt ·L tgt - V tgt ∣ exceeds the set tolerance, the target pitch L tgt and the target turbine speed n tgt .

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