Active control strategy, system, equipment and medium for power output of small cold flow rocket

Abstract

The invention belongs to the technical field of small cold-flow rockets, and relates to an active control strategy, system and device for power output of a small cold-flow rocket and a medium. The strategy comprises the following steps: setting a target flight height; in the rising process of the small rocket, the current flight height, the current flight speed, the fluid state of cold flow in a power storage cabin and the fluid state of a nozzle outlet are obtained in real time; according to the obtained fluid state of the cold flow in the power storage cabin and the obtained fluid state of the nozzle outlet, the real-time thrust of the small rocket is obtained through calculation based on the constructed thrust output calculation model; whether the current flight height of the small rocket reaches the target flight height or not is judged, if not, the target flight speed is adjusted in real time according to the current flight height of the small rocket, and a speed control strategy is executed; and if the flight height of the small rocket is larger than or equal to the target flight height, a # imgabs0 # control strategy is adopted, so that the flight height of the small rocket is controlled at the target flight height. The problem that a traditional model control strategy is complex is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of cold flow small rockets, and specifically relates to an active control strategy, system, equipment and medium for the power output of a cold flow small rocket. Background Art

[0002] As the aerospace industry enters a period of rapid development, reusable launch vehicles are constantly being updated, and their core technology lies in how to achieve faster response and more variable vector capability for rocket output thrust control. As a type of liquid launch vehicle, cold flow small rockets can safely and effectively replace liquid fuel combustion powered rockets to test and verify the working capabilities of rocket propulsion systems.

[0003] The traditional thrust control method is to use the Newton-Euler equation to obtain the system dynamics model of the small rocket to describe the movement and attitude of the small rocket, and then formulate the corresponding control strategy based on the system dynamics model. The control strategy based on the model is relatively complex, and due to the modeling error and the sensitivity and delay of the sensor, the control accuracy of the thrust output will be greatly reduced. Summary of the invention

[0004] The purpose of the present invention is to provide an active control strategy, system, equipment and medium for the power output of a cold flow small rocket to solve the problem of complex control strategies of traditional models.

[0005] The present invention is achieved through the following technical solutions: The present invention discloses an active control strategy for power output of a cold flow small rocket, comprising the following steps: S1. Set the target flight altitude; S2. During the ascent of the small rocket, the current flight altitude, flight speed, fluid state of the cold flow inside the power storage cabin, and fluid state of the nozzle outlet of the small rocket are obtained in real time; S3, according to the obtained fluid state of the cold flow inside the power storage cabin and the fluid state at the nozzle outlet, based on the constructed thrust output calculation model, calculate the real-time thrust of the small rocket; Determine whether the current flight altitude of the small rocket has reached the target flight altitude. If it has not reached the target flight altitude, adjust the target flight speed in real time according to the current flight altitude of the small rocket and execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, use The control strategy makes the flight altitude of the small rocket controlled at the target flight altitude; The real-time thrust of the small rocket is required in the control strategy.

[0006] Further, in S3, the thrust output calculation model is modeled according to the cold flow small rocket power output system; The cold flow small rocket power output system comprises a power storage cabin, a pipeline, an electromagnetic valve and a nozzle, and the cold flow is squeezed out of the power storage cabin and sprayed out by the nozzle; The expression of thrust output calculation model is:

[0007] in, Indicates the pressure of the cold flow inside the power storage cabin, represents the flow rate of the cold flow inside the power storage cabin, Indicates the water level of the cold flow inside the power storage compartment; Indicates the fluid pressure at the nozzle outlet. Indicates the flow rate of the fluid at the nozzle outlet. Indicates the fluid water level at the nozzle outlet; represents the density of the fluid, is the acceleration due to gravity, It is the loss along the pipeline; In S2, the fluid state at the nozzle outlet includes the fluid pressure at the nozzle outlet , Fluid flow rate at nozzle outlet and the fluid level at the nozzle outlet ; The fluid state of the cold flow inside the power storage cabin includes the pressure of the cold flow inside the power storage cabin , the flow rate of the cold flow inside the power storage cabin , the water level of the cold flow inside the power storage compartment .

[0008] Further, in S4, the speed control strategy is specifically:

[0009] So that the current height at time t The flight speed of the small rocket is controlled at ; represents the flying speed of the small rocket at time t, represents the target flight speed at time t, It is calculated using the thrust output calculation model.

[0010] The target flight speed is calculated according to the target flight speed calculation model.

[0011] Furthermore, the target flight speed calculation model is specifically as follows: the target flight speed is adjusted in real time according to the current flight altitude of the small rocket, and the expression is:

[0012] in, describe and the relationship between; represents the flight altitude at time t, represents the target flight speed at time t.

[0013] Furthermore, in S3, if the flight altitude of the small rocket is greater than or equal to the target flight altitude, use The control strategy makes the flight altitude of the small rocket controlled at the target flight altitude, specifically: The control target is switched to the ascending height, and the Control strategy, the output thrust is , so that the flight altitude of the small rocket is controlled at the target altitude , at this time the corresponding target flight speed is controlled to 0.

[0014] Furthermore, the output thrust The output thrust model is:

[0015] Thrust output time , For single The number of control cycles; where Duty cycle , , that is, the proportion of the valve opening time in the entire cycle within one cycle.

[0016] further, The control strategy is: in one control cycle Get the real-time gravity G of the small rocket and make the current output thrust =G, and the real-time thrust of the small rocket is calculated through the thrust output calculation model ; Duty Cycle Calculate the valve opening time , , which realizes the control of the thrust of the small rocket, making the output equivalent thrust ; Use multiple times at the same time Cycle control, control time thrust action time is .

[0017] The present invention discloses an active control system for power output of a cold flow small rocket, comprising: Setting module, used to set the target flight altitude; The data acquisition module is used to obtain the current flight altitude, flight speed, fluid state of the cold flow inside the power storage cabin, and fluid state of the nozzle outlet of the small rocket in real time during the small rocket's ascent; A calculation module stores a thrust output calculation model, which is used to calculate the real-time thrust of the small rocket based on the thrust output calculation model according to the acquired fluid state of the cold flow inside the power storage cabin and the fluid state at the nozzle outlet; the calculation module stores a target flight speed calculation model, which adjusts the target flight speed in real time according to the current flight altitude of the small rocket; The judgment module is used to judge whether the current flight altitude of the small rocket reaches the target flight altitude. If the target flight altitude is not reached, the calculation module and the speed control module are started; the calculation module calculates the target flight speed; the speed control module is used to execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, start Control module; Control module, using The control strategy ensures that the flight altitude of the small rocket is controlled at the target flight altitude.

[0018] The present invention discloses a computer device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the processor implements the steps of the active control strategy for the power output of the cold flow small rocket.

[0019] The present invention discloses a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the active control strategy of the power output of the cold flow small rocket are implemented.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention discloses an active control strategy for the power output of a cold flow small rocket. The real-time thrust is calculated according to the fluid state of the power storage cabin and the nozzle outlet, which can accurately understand the current power output of the small rocket. At the same time, it is determined whether the current flight altitude reaches the target flight altitude. If not, the target flight speed is adjusted in real time according to the current flight altitude and the speed control strategy is executed. This is a dynamic adjustment mechanism. When the small rocket is far away from the target flight altitude, the target flight speed can be appropriately increased to speed up the ascent process; when approaching the target flight altitude, the speed can be reduced to approach the target more accurately. This control strategy can effectively prevent the small rocket from flying over or failing to reach the target flight altitude, and realize accurate flight altitude control.

[0021] The constructed thrust output calculation model is used to calculate the real-time thrust according to the fluid state of the cold flow inside the power storage cabin and the fluid state of the nozzle outlet. This enables real-time control of the power output, and when the flight altitude of the small rocket is greater than or equal to the target flight altitude, the DW control strategy is used to control the flight altitude using the real-time thrust. The DW control can achieve the output of any fixed value of the power of the cold flow small rocket without relying on the overall system dynamics model of the small rocket, effectively solving the shortcomings of the cold flow small rocket's power output curve with a large drop, unstable power output, and relatively short action time.

[0022] The present invention is compatible with most rocket control plans. It only needs to obtain the flight plan of the flight speed of the small rocket at different flight altitudes during the ascent. The ascent altitude control and speed control of the cold flow small rocket can be realized through the present invention, which effectively verifies the recyclability of the cold flow small rocket. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the structural diagram of the cold flow small rocket; Among them, 1. fairing; 2. electronic component compartment; 3. electronic components; 4. hull; 5. power storage compartment; 6. pipeline; 7. electromagnetic valve; 8. nozzle; Figure 2 This is the thrust simulation diagram of the fully opened valve of the power system; Figure 3 This is the principle diagram of the active control algorithm; Figure 4 is the thrust output curve; Figure 5 This is the simulation result of DW control speed; Figure 6 Simulation results for DW control height; Figure 7 This is the simulation result of DW control speed (T=0.001s); Figure 8 It is a three-dimensional coordinate system established with the rocket's center of mass as the origin. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention more clear, the following is further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, not all embodiments.

[0025] The components described and shown in the drawings and embodiments of the present invention may be arranged and designed in various configurations. Therefore, the detailed description of the embodiments of the present invention provided in the following drawings is not intended to limit the scope of the claimed invention, but merely represents a selected embodiment of the present invention. Based on the drawings and embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0026] It should be noted that the terms "comprises", "includes" or any other variations are intended to cover non-exclusive inclusion, so that a process, element, method, article or equipment that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to the process, element, method, article or equipment.

[0027] The features and performances of the present invention are further described in detail below in conjunction with the embodiments.

[0028] like Figure 1 As shown, the cold flow small rocket includes: a fairing 1, an electronic component compartment 2 and a hull 4, wherein the electronic component compartment 2 is provided with an electronic component 3, and the hull 4 is provided with a power storage compartment 5, a pipeline 6, an electromagnetic valve 7, and a nozzle 8. Among them, A is the liquid cross section in the power storage compartment 5, which is also the cross section where the high-pressure gas is located, B is the outlet cross section of the power storage compartment 5, C is the valve cross section, and D is the nozzle outlet cross section. The outlet of the power storage compartment 5 is connected to the nozzle 8 through the pipeline 6, and the electromagnetic valve 7 is installed in the pipeline 6.

[0029] From a design perspective, the present invention discloses an active control strategy for the power output of a cold flow small rocket, including the following steps: Step 1: First, model the power output system of the cold flow rocket to obtain the thrust output calculation model; like Figure 1 As shown, the cold flow small rocket power output system consists of a power storage cabin 5, a pipeline 6, an electromagnetic valve 7 and a nozzle 8. The cold flow is squeezed out of the power storage cabin 5 and sprayed out by the nozzle 8 to obtain a high-speed fluid, thereby generating a reaction force as the thrust of the small rocket.

[0030] According to Bernoulli's principle, that is, the law of conservation of fluid mechanical energy, the sum of kinetic energy, gravitational potential energy and pressure potential energy is a constant, as shown in the following formula:

[0031] Among them, pressure , flow rate and water level Indicates the cold flow state inside the power storage compartment 5; Indicates the fluid status at the outlet of nozzle 8; Indicates the density of the fluid; is the acceleration due to gravity; is the loss along pipeline 6, which is a constant value.

[0032] Based on the relationship between pressure and force, the thrust equation of the small rocket, that is, the thrust output calculation model, is obtained, specifically:

[0033] Wherein, A is the outlet area of ​​the nozzle 8.

[0034] Step 2: Establish a small rocket dynamics system to describe its position and velocity changes; like Figure 8 As shown, first, a three-dimensional coordinate system is established with the rocket's center of mass as the origin O (due to the rocket's power loss, the center of mass is a dynamic point), where O1 is the thrust application point.

[0035] Here we only consider The force in the axial direction, combined with Newton's second law, is

[0036] in, is the mass of the small rocket at time t, which is changing; represents the thrust of the small rocket at time t; It represents the resistance encountered by the small rocket during its ascent.

[0037] So we can get the ascent acceleration of the small rocket , ; So we can get the speed and displacement calculation formula of the small rocket:

[0038] in, represents the speed of the small rocket, represents the displacement of the small rocket, and t0 represents the time.

[0039] Step 3: Control target selection and overall control plan Here, the control target of the small rocket during its ascent is the target flight altitude. and target flight speed , among which, the flight altitude control has a higher priority than the flight speed control. Real-time flight altitude and flight speed Real-time feedback is provided by sensors. The overall control scheme is implemented in two stages as shown below: Phase 1: , the real-time altitude of the small rocket did not reach the target flight altitude , the control target is the target flight speed , and the target flight speed Real-time adjustment based on the rocket's flight altitude, the expression is:

[0040] in, describe and some kind of relationship between represents the flight altitude at time t, represents the target flight speed at time t.

[0041] On this basis, the speed control strategy is as follows:

[0042] So that the current height The target flight speed of the small rocket is controlled at .

[0043] Phase 2: , the small rocket reaches the target flight altitude in real time, and the control target switches to the ascending altitude , directly adopt Control strategy, the output thrust is , so that the flight altitude of the small rocket is controlled at the target altitude , the corresponding speed control target is .

[0044] Step 4: Design Control algorithm and Thrust output model The present invention proposes The basic principle of the control algorithm is based on the modulation (Pulse Width Modulation, PWM) principle, also known as the impulse (power) equivalent principle, which is a technology that controls the output power of electronic equipment by adjusting the duty cycle of the signal. The thrust output model of the control algorithm is derived as follows: First, combined with the above, assuming that when the valve is fully open, the thrust output by the nozzle 8 is And keep the constant size for a certain period of time. The single control cycle time of the control algorithm is , the duration of full valve opening in this cycle is , so according to the impulse equivalence principle, The control algorithm output thrust model is:

[0045] The thrust output time , For single The number of control cycles. Duty cycle , , that is, the proportion of the valve opening time in the entire cycle within one cycle.

[0046] In summary, the present invention The control strategy is: in one control cycle Within, with duty cycle Calculate the valve opening time , , which realizes the control of the thrust of the small rocket, making the output equivalent thrust . Use multiple times at the same time Cycle control, control time thrust action time is .

[0047] Combined with the performance of the existing electromagnetic valve 7 and the cold flow power storage cabin 5, the power output system, control system and sensor system of the cold flow small rocket are completed, which can provide closed-loop control of the thrust output.

[0048] In practical application, such as Figure 3 As shown, the present invention discloses an active control strategy for power output of a cold flow small rocket, comprising the following steps: S1. Set the target flight altitude; S2. During the ascent of the small rocket, the current flight altitude, flight speed, fluid state of the cold flow inside the power storage cabin 5, and fluid state of the nozzle 8 outlet of the small rocket are obtained in real time; S3, according to the obtained fluid state of the cold flow inside the power storage cabin 5 and the fluid state at the outlet of the nozzle 8, based on the constructed thrust output calculation model, calculate the real-time thrust of the small rocket; Determine whether the current flight altitude of the small rocket has reached the target flight altitude. If it has not reached the target flight altitude, adjust the target flight speed in real time according to the current flight altitude of the small rocket and execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, use The control strategy makes the flight altitude of the small rocket controlled at the target flight altitude; The real-time thrust of the small rocket is required in the control strategy.

[0049] Verification Example The present invention provides a strategy for active control of power output of a cold flow rocket. Figure 1As shown, the cold flow small rocket includes a fairing 1, a hull 4, a power storage cabin 5, a pipeline 6, an electromagnetic valve 7, a nozzle 8 and other parts.

[0050] According to Bernoulli's principle, the thrust output calculation model of the power system in this embodiment is established:

[0051] in, The thrust generated by the nozzle 8 outlet, using pressure , flow rate and water level Indicates the cold flow state inside the cabin. Indicates the fluid status at the nozzle 8 outlet, represents the density of the fluid, is the acceleration due to gravity, is the loss along pipeline 6.

[0052] Next, the axial (z-axis) motion equation of the small rocket is established based on Newton's laws, as shown below.

[0053]

[0054] in, is the mass of the small rocket, is the acceleration, , are real-time speed and altitude respectively, is the air resistance during ascent.

[0055] In this embodiment, the above-mentioned power system further combines the above-mentioned fluid mechanics equations and Newton's equations, and further combines the fluid continuity equation, pressure conservation equation, etc. to supplement and improve the entire small rocket power model, and uses Matlab software to model. This is not the focus of the present invention, so it will not be repeated.

[0056] The above established dynamic system model can simulate the real-time thrust , the simulation results are shown in Figure 2 The thrust generated by high-pressure water drops rapidly from 600N to 300N within 0.4s and then drops to 0. Therefore, the control of thrust is very limited in time, and even for the main control chip, it is not within the responsive time range. However, due to the structural design conditions and the structural performance of the power cabin, the power output cannot be extended.

[0057] According to the control scheme proposed by the present invention, Figure 3 As shown, the control target of the small rocket during its ascent is the target flight altitude. and target flight speed , real-time flight altitude and flight speed Through real-time feedback from sensors, the control scheme of the small rocket is implemented in two stages, as shown below.

[0058] Phase 1: , the real-time height of the small rocket has not reached the target height, and the control target is the target flight speed , and the target flight speed Can be adjusted in real time according to the rocket's flight altitude:

[0059] in, describe and There is a certain relationship between them. On this basis, the speed control strategy is as follows:

[0060] So that the current height The flight speed of the small rocket is controlled at .

[0061] Phase 2: , the real-time height of the small rocket reaches the target height, and the control target switches to the ascending height , directly adopt Control strategy to keep the rocket's flight altitude at the target altitude , the corresponding speed control target is .

[0062] In summary, no matter which stage, The control strategy is to make the real-time speed of the small rocket Maintain a target value Therefore, this embodiment The control goal of the algorithm is to make in close to The acceleration is zero, so the target thrust can be obtained as:

[0063] in, is the total mass of the small rocket, is the acceleration due to gravity.

[0064] Through the overall control system of the small rocket, real-time gravity can be obtained, and through the thrust output calculation model in this scheme, real-time thrust can be obtained , so we can get in one control cycle Internal, duty cycle , so the valve opening time is With this duty cycle By periodically controlling the electromagnetic valve 7, the actual thrust output of the small rocket can be made equal to its gravity, so as to realize speed control at different stages and further realize the altitude control of the liquid rocket engine.

[0065] In this embodiment, the response time of the electromagnetic valve 7 selected is 0.01s, so The single limit cycle of the control strategy is set to 0.01s. At the same time, in this embodiment, the target height is set to 2m, and the speed of the ascending flight process is set to 1m / s, and the simulation is performed, and the results are as follows.

[0066] Figure 4 The real-time valve thrust output curve of the small rocket rising. It can be seen that the thrust switches back and forth between 0 and the thrust generated by the full opening of the electromagnetic valve 7, and the thrust size of each opening is close to each other and the difference is relatively small. Compared with the simulation curve of the valve fully open in Figure 2, The control effectively extends the thrust output time to 8.5s, and at the same time can control the "equivalent" thrust output to be equal to gravity.

[0067] like Figure 5 As shown, under the output of equivalent thrust, during the ascent phase of the small rocket, the real-time speed is controlled at around 1m / s. Figure 6 This is the flight line height curve of the small rocket. Before reaching the target height of 2m, the small rocket rises at a constant speed and finally hovers at a height of 2m, which effectively verifies the important role of this control algorithm in achieving the recoverability of the cold flow small rocket.

[0068] Finally, when the response time of the electromagnetic valve 7 is faster, that is, a single The shorter the control period, the better the control effect of this algorithm on the thrust size and time. Figure 7 As shown in the figure, setting the single control period to 0.001s can obtain more precise speed control.

[0069] The present invention also discloses an active control system for power output of a cold flow small rocket, comprising: Setting module, used to set the target flight altitude; The data acquisition module is used to obtain the current flight altitude, flight speed, fluid state of the cold flow inside the power storage cabin 5 and the fluid state of the nozzle 8 outlet of the small rocket in real time during the small rocket's ascent; A calculation module stores a thrust output calculation model, which is used to calculate the real-time thrust of the small rocket based on the thrust output calculation model according to the acquired fluid state of the cold flow inside the power storage cabin 5 and the fluid state at the outlet of the nozzle 8; the calculation module stores a target flight speed calculation model, which adjusts the target flight speed in real time according to the current flight altitude of the small rocket; The judgment module is used to judge whether the current flight altitude of the small rocket reaches the target flight altitude. If the target flight altitude is not reached, the calculation module and the speed control module are started; the calculation module calculates the target flight speed; the speed control module is used to execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, start Control module; Control module, using The control strategy ensures that the flight altitude of the small rocket is controlled at the target flight altitude.

[0070] The present invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the active control strategy of the power output of the cold flow small rocket are implemented. The memory may include a memory, such as a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk memory, etc. The processor, the network interface, and the memory are interconnected through an internal bus, and the internal bus may be an industrial standard architecture bus, a peripheral component interconnection standard bus, an extended industrial standard structure bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The memory is used to store programs. Specifically, the program may include a program code, and the program code includes computer operation instructions. The memory may include a memory and a non-volatile memory, and provide instructions and data to the processor.

[0071] The present invention also discloses a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the active control strategy of the power output of the cold flow small rocket are implemented. Specifically, the computer-readable storage medium includes, but is not limited to, for example, a volatile memory and / or a non-volatile memory. The volatile memory may include a random access memory and / or a cache memory, etc. The non-volatile memory may include a read-only memory, a hard disk, a flash memory, an optical disk, a magnetic disk, etc.

[0072] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) containing computer-usable program code.

[0073] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0074] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0075] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An active control strategy for the power output of a cold flow small rocket, characterized in that: The following steps are involved: S1. Set the target flight altitude; S2. During the ascent of the small rocket, the current flight altitude, flight speed, the fluid state of the cold flow inside the power storage cabin (5), and the fluid state at the outlet of the nozzle (8) of the small rocket are obtained in real time; S3, according to the obtained fluid state of the cold flow inside the power storage cabin (5) and the fluid state at the outlet of the nozzle (8), based on the constructed thrust output calculation model, calculate the real-time thrust of the small rocket; Determine whether the current flight altitude of the small rocket has reached the target flight altitude. If it has not reached the target flight altitude, adjust the target flight speed in real time according to the current flight altitude of the small rocket and execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, use The control strategy makes the flight altitude of the small rocket controlled at the target flight altitude; The real-time thrust of the small rocket is required in the control strategy.

2. The active control strategy for power output of a cold flow small rocket according to claim 1 is characterized in that: In S3, the thrust output calculation model is modeled according to the cold flow small rocket power output system; The cold flow small rocket power output system comprises a power storage cabin (5), a pipeline (6), an electromagnetic valve (7) and a nozzle (8), and the cold flow is squeezed out of the power storage cabin (5) and sprayed out from the nozzle (8); The expression of thrust output calculation model is: in, represents the pressure of the cold flow inside the power storage compartment (5), represents the flow rate of the cold flow inside the power storage compartment (5), Indicates the water level of the cold flow inside the power storage compartment (5); Indicates the fluid pressure at the nozzle (8) outlet, represents the fluid flow rate at the outlet of the nozzle (8), Indicates the fluid water level at the outlet of the nozzle (8); represents the density of the fluid, is the acceleration due to gravity, is the loss along the pipeline (6); In S2, the fluid state at the outlet of the nozzle (8) includes the fluid pressure at the outlet of the nozzle (8). , Fluid flow rate at nozzle (8) outlet and the fluid level at the nozzle (8) outlet ; The fluid state of the cold flow inside the power storage cabin (5) includes the pressure of the cold flow inside the power storage cabin (5). , the flow rate of the cold flow inside the power storage compartment (5) , the water level of the cold flow inside the power storage compartment (5) .

3. The active control strategy for power output of a cold flow small rocket according to claim 1 is characterized in that: In S4, the speed control strategy is as follows: So that the current height at time t The flight speed of the small rocket is controlled at ; represents the flying speed of the small rocket at time t, represents the target flight speed at time t, Calculated using the thrust output calculation model; The target flight speed is calculated according to a target flight speed calculation model.

4. The active control strategy for power output of a cold flow small rocket according to claim 3 is characterized in that: The target flight speed calculation model is specifically as follows: the target flight speed is adjusted in real time according to the current flight altitude of the small rocket, and the expression is: in, describe and the relationship between; represents the flight altitude at time t, represents the target flight speed at time t.

5. The active control strategy for power output of a cold flow small rocket according to claim 1 is characterized in that: In S3, if the flight altitude of the small rocket is greater than or equal to the target flight altitude, use The control strategy makes the flight altitude of the small rocket controlled at the target flight altitude, specifically: The control target is switched to the ascending height, and the Control strategy, the output thrust is , so that the flight altitude of the small rocket is controlled at the target altitude , at this time the corresponding target flight speed is controlled to 0.

6. The active control strategy for power output of a cold flow small rocket according to claim 3 or 5, characterized in that: Output thrust The output thrust model is: Thrust output time , For single The number of control cycles; where Duty cycle , , that is, the proportion of the valve opening time in the entire cycle within one cycle.

7. The active control strategy for power output of a cold flow small rocket according to claim 1 is characterized in that: The control strategy is: in one control cycle Get the real-time gravity G of the small rocket and make the current output thrust =G, and the real-time thrust of the small rocket is calculated through the thrust output calculation model ; Duty Cycle Calculate the valve opening time , , which realizes the control of the thrust of the small rocket, making the output equivalent thrust ; Use multiple times at the same time Cycle control, control time thrust action time is .

8. An active control system for the power output of a cold flow small rocket, characterized in that: include: Setting module, used to set the target flight altitude; A data acquisition module is used to acquire the current flight altitude, flight speed, fluid state of the cold flow inside the power storage cabin (5) and fluid state of the nozzle (8) outlet of the small rocket in real time during the small rocket's ascent process; A calculation module, in which a thrust output calculation model is stored, and is used to calculate the real-time thrust of the small rocket based on the thrust output calculation model according to the acquired fluid state of the cold flow inside the power storage cabin (5) and the fluid state at the outlet of the nozzle (8); the calculation module stores a target flight speed calculation model, and adjusts the target flight speed in real time according to the current flight altitude of the small rocket; The judgment module is used to judge whether the current flight altitude of the small rocket reaches the target flight altitude. If the target flight altitude is not reached, the calculation module and the speed control module are started; the calculation module calculates the target flight speed; the speed control module is used to execute the speed control strategy; If the flight altitude of the small rocket is greater than or equal to the target flight altitude, start Control module; Control module, using The control strategy ensures that the flight altitude of the small rocket is controlled at the target flight altitude.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the active control strategy of the power output of the cold flow small rocket as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, the steps of the active control strategy for the power output of the cold flow small rocket as described in any one of claims 1 to 7 are implemented.

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