Wide-range high-precision piezoelectric cold-gas variable thrust module and multi-mode cooperative control method

Abstract

The present application relates to the technical field of spacecraft, and particularly relates to a wide-range high-precision piezoelectric cold-gas variable thrust module and a multi-mode cooperative control method. The piezoelectric cold-gas variable thrust module comprises a piezoelectric proportional valve, a nozzle throat throttling unit, a sensor group, a shell assembly and a module controller. The module controller is configured to selectively control the piezoelectric proportional valve in an open loop, a flow closed loop, a displacement closed loop or a displacement-flow double closed loop working mode according to a thrust instruction and a sensor signal. Through the multi-mode selective control of the module controller, the module can realize high-precision and fast-response thrust output in a thrust range of 10 ‑2 μN to 10 3 μN. The present application also provides a corresponding multi-mode cooperative control method, which realizes high-performance output of the module in the full thrust range through adaptive control of the working mode and the thrust range. The present application solves the technical problem that the prior art cannot simultaneously realize a wide thrust range, high precision and fast response.

Description

Technical Field

[0001] This invention relates to the field of spacecraft technology, and in particular to a wide-range, high-precision piezoelectric-cooled gas-driven thrust module and a multi-mode cooperative control method. Background Technology

[0002] The micro-Newton level cold gas variable thrust module is a key component for performing cutting-edge space science missions such as space gravitational wave detection and high-precision Earth gravity field mapping. With increasing mission requirements, demands are being placed on the thrust module's performance to cover a wide thrust range (e.g., 10). -2 It must meet stringent requirements, including μN to 10³ μN, high thrust resolution (e.g., 0.1 μN), fast response (e.g., response time <50 ms in certain thrust ranges), and stable operation in complex space environments (wide temperature range, strong electromagnetic interference).

[0003] Existing micro-Newton level cold gas thrust technologies often only meet the requirements for a few of the aforementioned indicators, making it difficult to simultaneously achieve all high-performance targets. For example, some technologies have a narrow thrust range; some have insufficient resolution or slow response in the low-thrust range; and some have poor environmental adaptability and unstable on-orbit performance. These technological limitations severely restrict the development of high-precision space missions. Summary of the Invention

[0004] The purpose of this invention is to provide a wide-range, high-precision piezoelectric-cooled gas variable thrust module and a multi-mode collaborative control method for the piezoelectric-cooled gas variable thrust module, so as to solve the main technical problem that the existing technology cannot simultaneously achieve a wide thrust range, high precision and fast response.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a wide-range, high-precision piezoelectric-cooled gas-driven thrust module, comprising:

[0006] The piezoelectric proportional valve includes an inlet connector, a bellows, an armature assembly, and a piezoelectric drive assembly. The bellows is used to achieve an elastic connection between the inlet connector and the armature assembly. The piezoelectric drive assembly is used to provide the driving force to drive the armature assembly to move axially. The armature assembly cooperates with the valve port through axial movement to control the flow channel opening.

[0007] The nozzle throat throttling unit, which is a micro-Newton Laval nozzle, works in conjunction with the valve needle of the armature assembly to adjust the thrust by changing the throat throttling area;

[0008] The sensor group includes a temperature sensor for collecting the temperature at various points on the module, a flow sensor for providing the module's flow rate signal, and a valve core position sensor for providing the valve core position signal.

[0009] The housing assembly encapsulates the piezoelectric proportional valve, the nozzle throat throttling unit, and the sensor assembly within it;

[0010] The module controller, electrically connected to the sensor array and the piezoelectric proportional valve, is configured to selectively control the piezoelectric proportional valve in open-loop, flow-closed-loop, displacement-closed-loop, or displacement-flow dual-closed-loop operating modes based on thrust commands and sensor signals. Through this multi-mode selective control, the module can achieve [a specific operating range] within 10 [units / areas]. -2 μN to 10 3 Achieve high-precision and fast-response thrust output within a thrust range of μN.

[0011] Optionally, the piezoelectric drive assembly includes at least one set of piezoelectric ceramics, each set of piezoelectric ceramics comprising two piezoelectric ceramic plates configured to extend in opposite directions under a drive voltage to jointly push or pull the drive frame.

[0012] Optionally, the armature assembly includes a leaf spring configured to center the armature assembly and provide a sealing force, thereby enabling the valve needle to move stably within the flow channel of the sealing module and achieve a seal.

[0013] Optionally, the armature assembly also includes an armature and a valve pin disposed at the front end of the armature, wherein the armature is provided with an airflow channel and the front end of the airflow channel is provided with multiple air holes in the circumferential direction.

[0014] The piezoelectric air-cooled thrust converter module also includes a support assembly, which is fixedly connected to the housing of the piezoelectric proportional valve. The support assembly includes an upper support block and a lower support block. The upper support block has an upper through hole for the armature to pass through and fit against the armature. The lower support block has a lower through hole with a diameter larger than the outer diameter of the armature, so that there is a gap between the armature passing through the lower support block and the lower through hole, forming an airflow buffer chamber. A leaf spring is set between the upper support block and the lower support block. The armature passes through the upper through hole and the lower through hole. The valve needle is inserted into the flow channel hole of the sealing module. The air hole communicates with the airflow buffer chamber and the flow channel hole of the sealing module.

[0015] Optionally, the support assembly is connected to the housing of the piezoelectric proportional valve via a base. The base includes a hollow column and an annular stop block disposed at the lower end of the hollow column. The outer periphery of the hollow column is attached to the inner wall of the housing of the piezoelectric proportional valve, and the annular stop block is located outside the housing of the piezoelectric proportional valve and abuts against the lower end of the housing of the piezoelectric proportional valve.

[0016] The support assembly is fixedly installed in the hollow cylinder. The sealing module and the nozzle throat throttling unit are installed in the hollow cylinder. The sealing module is located between the support assembly and the nozzle throat throttling unit. The sealing module includes a sealing pressure block and a sealing block. The sealing block is pressed against the nozzle throat throttling unit. The sealing pressure block is located between the support assembly and the sealing block. The sealing pressure block is provided with a valve needle through hole. The valve needle through hole is connected to the airflow buffer chamber. After the valve needle passes through the sealing block, it is inserted into the flow channel hole of the sealing block.

[0017] Optionally, the valve core position sensor operates based on the principle of capacitance change or the Wheatstone bridge principle, and its sensing head is fixed on the bellows or armature assembly to follow the movement of the armature assembly.

[0018] Optionally, the flow sensor includes a flow channel and a MEMS chip, and non-metallic support plates are mounted on both sides of the flow channel. The non-metallic support plates contact the housing assembly to enhance shock and vibration resistance.

[0019] Optionally, the housing assembly includes a cylindrical housing, a top cover, and a bottom cover. The cylindrical housing is a one-piece molded titanium alloy housing, and the top cover and bottom cover are connected to the cylindrical housing to form a sealed space.

[0020] Optionally, the internal cables of the piezoelectric air-cooled thrust module are all processed using a twisted-pair and shielded process, and all electrical signals are output uniformly through no more than two electrical connectors.

[0021] Optionally, the module controller is an external propulsion system circuit box.

[0022] Optionally, the open-loop operating mode is configured as follows: the module controller receives the thrust command, directly calculates the corresponding drive voltage based on the preset thrust-drive voltage mapping relationship, and outputs it to the piezoelectric proportional valve;

[0023] The flow closed-loop working mode is configured as follows: the module controller receives the thrust command and converts it into the target flow value. Then, using the flow signal fed back in real time by the flow sensor as the control target, the flow closed-loop control algorithm is used to adjust the drive voltage output to the piezoelectric proportional valve so that the actual flow converges to the target flow value.

[0024] The displacement closed-loop working mode is configured as follows: the module controller receives the thrust command and converts it into the target valve core displacement value. Then, taking the valve core position signal fed back by the valve core position sensor in real time as the control target, the displacement closed-loop control algorithm is used to adjust the drive voltage output to the piezoelectric proportional valve so that the actual valve core displacement converges to the target valve core displacement value.

[0025] The displacement and flow dual closed-loop operating mode is configured as follows: the module controller first performs coarse closed-loop control of displacement using the feedback signal from the valve core position sensor, and then performs precise closed-loop control of flow using the feedback signal from the flow sensor.

[0026] Secondly, the present invention also provides a multi-mode cooperative control method for a piezoelectric-cooled gas-driven variable thrust module.

[0027] The module includes a piezoelectric proportional valve, a flow sensor, a valve core position sensor, and a module controller. The method includes the following steps:

[0028] Steps for receiving thrust commands: The module controller receives thrust commands from the host computer;

[0029] Operating mode decision and execution steps: Based on the magnitude of the thrust command and / or the requirements for dynamic performance of thrust changes, select and execute the corresponding control operating mode to drive the piezoelectric proportional valve, wherein:

[0030] When rapid and coarse thrust adjustment is required, an open-loop operating mode is adopted: the module controller directly outputs the drive voltage based on the preset thrust-drive voltage mapping relationship;

[0031] When the thrust value corresponding to the thrust command is less than 10 2 When the thrust resolution is required to be ≤0.1 μN and the response time is <50ms, the displacement closed-loop working mode or the displacement-flow dual closed-loop working mode shall be adopted. The displacement closed-loop working mode uses the feedback signal of the valve core position sensor as the target for precise control. The displacement-flow dual closed-loop working mode first uses the feedback signal of the valve core position sensor to perform rapid displacement coarse closed loop, and then uses the feedback signal of the flow sensor to perform precise flow closed loop.

[0032] When the thrust value corresponding to the thrust command is 10 2 μN to 10 3 Within the μN range, and with a thrust resolution ≤1μN and a response time <250 ms required, a flow closed-loop working mode or a displacement-flow dual closed-loop working mode is adopted; the flow closed-loop working mode uses the feedback signal from the flow sensor as the target for stable control.

[0033] Through adaptive control of operating modes and thrust range, the module can achieve 10 -2 μN to 10 3 Within a thrust range of μN, achieve a thrust of less than 10. 2 At a resolution ≤ 0.1 μN and a response time < 50 ms, the thrust is 10 μN. 2 μN to 10 3 Performance output with resolution ≤1μN and response time <250 ms at μN.

[0034] The above-described technical solution of the present invention has the following advantages:

[0035] The piezoelectric cold gas variable thrust module provided by this invention successfully achieves multi-level (10) thrust across five orders of magnitude (10) on a single module by integrating a piezoelectric proportional valve, a nozzle throat throttling unit, a multi-sensor group, and a module controller supporting multi-mode selection into a single housing assembly. -2 μN to 10 3 With its wide thrust range coverage (μN), high-precision thrust output at the micronewton level, and rapid response capability at the millisecond level, it fundamentally solves the inherent technical contradiction in existing technologies where it is difficult to achieve both wide range, high precision, and fast response.

[0036] The multi-mode cooperative control method for piezoelectric-cooled gas-varying thrust modules provided by this invention establishes an intelligent decision-making mechanism that automatically selects and executes the optimal control mode based on the thrust command magnitude. This enables the piezoelectric-cooled gas-varying thrust module to dynamically adapt to the performance requirements of different thrust ranges, thereby systematically ensuring its performance across the entire thrust range (10). -2 μN to 10 3 Within μN, it can stably achieve the preset high resolution and fast response performance indicators, realizing the leap from fixed mode to adaptive optimization of control strategy. Attached Figure Description

[0037] The accompanying drawings are provided for illustrative purposes only, and the proportions and quantities of the components in the drawings may not be consistent with the actual product.

[0038] Figure 1 This is a cross-sectional schematic diagram of a piezoelectric air-cooled variable thrust module according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of a piezoelectric proportional valve according to an embodiment of the present invention;

[0040] Figure 3 This is a cross-sectional schematic diagram of a piezoelectric proportional valve according to an embodiment of the present invention;

[0041] Figure 4 yes Figure 3 A partially enlarged cross-sectional view of a medium-voltage electro-proportional valve;

[0042] Figure 5 This is a cross-sectional schematic diagram of a flow sensor according to an embodiment of the present invention;

[0043] Figure 6 This is an enlarged schematic diagram of a nozzle throat throttling unit in an embodiment of the present invention;

[0044] Figure 7 This is a schematic diagram of the control logic of a piezoelectric cooling gas variable thrust module in an embodiment of the present invention.

[0045] In the picture:

[0046] 100: Piezoelectric proportional valve;

[0047] 110: Inlet connector;

[0048] 120: Corrugated pipe;

[0049] 130: Armature assembly;

[0050] 131: Armstock;

[0051] 1311: Stomata;

[0052] 132: Valve needle;

[0053] 133: Leaf spring;

[0054] 140: Piezoelectric drive assembly;

[0055] 141: Drive rack;

[0056] 142: Piezoelectric ceramic sheet;

[0057] 143: Cap;

[0058] 144: Disc spring;

[0059] 150: The housing of the piezoelectric proportional valve;

[0060] 160: Support components;

[0061] 161: Upper support block;

[0062] 162: Lower support block;

[0063] 163: Airflow buffer chamber;

[0064] 170: Base;

[0065] 180: Sealing module;

[0066] 181: Sealing block;

[0067] 182: Sealing block;

[0068] 200: Nozzle throat throttling unit;

[0069] 300: Temperature sensor;

[0070] 400: Flow sensor;

[0071] 401: Flow channel;

[0072] 402: Circuit board for the flow sensor;

[0073] 403: Non-metallic support plate;

[0074] 404: Metal ring;

[0075] 500: Valve spool position sensor;

[0076] 501: Circuit board for valve core position sensor;

[0077] 502: The sensing head of the valve core position sensor;

[0078] 600: Housing assembly;

[0079] 601: Cylindrical outer shell;

[0080] 602: Top cover;

[0081] 603: Bottom cover;

[0082] 700: Module entry point;

[0083] 800: Electrical connector;

[0084] 900: Cable. Detailed Implementation

[0085] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0086] like Figures 1 to 7 As shown, this embodiment provides a wide-range, high-precision piezoelectric-cooled gas-varying thrust module. Its core lies in the combination of a unique mechanical structure design and an intelligent multi-mode control strategy to collaboratively solve the technical challenge of simultaneously achieving wide range, high precision, and fast response in the field of micro-Newton thrust.

[0087] The variable thrust module mainly includes a piezoelectric proportional valve 100, a nozzle throat throttling unit 200, a sensor group, a housing assembly 600, and a module controller.

[0088] The piezoelectric proportional valve 100 is the actuator of this module. See also... Figure 2 and Figure 3 It includes an inlet connector 110, a bellows 120, an armature assembly 130, and a piezoelectric drive assembly 140. One end of the bellows 120 is welded to the inlet connector 110, and the other end is welded to the armature assembly 130, achieving dynamic isolation and sealing between the high-pressure gas passage and the piezoelectric actuator, while providing flexible space for the axial movement of the armature assembly 130. The piezoelectric drive assembly 140 provides the precise driving force to drive the armature assembly 130 to move axially. Through its axial movement, the armature assembly 130 causes its front-end valve needle 132 to engage with the valve port, thereby precisely controlling the opening of the gas flow passage.

[0089] See Figure 1 and Figure 6 The nozzle throat throttling unit 200 is a micro-Newton Laval nozzle, which is precisely matched with the tip of the valve needle 132 of the armature assembly 130. By axial displacement of the valve needle 132, the effective throttling area of ​​the nozzle throat can be continuously and precisely changed, thereby achieving linear adjustment of thrust.

[0090] See Figure 1 and Figure 3 The sensor array is used to provide real-time feedback for closed-loop control. It includes:

[0091] Temperature sensors 300 are distributed at key nodes such as module inlet 700, flow sensor 400 inlet and outlet, and piezoelectric proportional valve 100 inlet and outlet. They are used to collect temperature signals under a wide temperature range environment for the controller to perform performance compensation. In this embodiment, temperature sensor 300 is a thermistor.

[0092] Flow sensor 400: Used to provide the module with a real-time quality flow signal.

[0093] Valve core position sensor 500: used to provide real-time displacement signals for armature assembly 130.

[0094] See Figure 1 The housing assembly 600 serves as the encapsulation and protection structure for the module, encapsulating all core components such as the piezoelectric proportional valve 100, the nozzle throat throttling unit 200, and the sensor group within it, forming a whole.

[0095] The module controller (not shown in the figure; in this embodiment, the module controller is an external propulsion system circuit box) is electrically connected to the sensor group and the piezoelectric proportional valve 100 via an electrical connector 800. This controller is programmed to implement multiple operating modes and can intelligently and selectively control the piezoelectric proportional valve 100 in open-loop, flow-closed-loop, displacement-closed-loop, or displacement-flow dual-closed-loop operating modes based on thrust commands and sensor signals.

[0096] In this embodiment, the module works as follows: When the host computer receives the thrust command, the module controller collects signals from the flow sensor, flow sensor temperature, valve core position sensor displacement, and inlet and outlet temperature signals of the piezoelectric proportional thruster. These signals, in conjunction with different preset operating modes, drive the piezoelectric proportional thruster to work, causing the module flow rate to converge to the thrust calibration value, thereby obtaining the required thrust. When a larger thrust is needed, the driving voltage increases, resulting in a larger opening of the proportional thruster and thus a larger thrust. When a smaller thrust is needed, the driving voltage decreases, resulting in a smaller opening of the proportional thruster and thus a smaller thrust.

[0097] Through the multi-mode selective control of the aforementioned module controller, the variable thrust module of this embodiment is configured to be able to achieve 10 -2 μN to 10 3 It operates over a thrust range of up to five orders of magnitude with μN and achieves high-precision and fast-response thrust output.

[0098] In one example, the piezoelectric drive assembly 140 is further optimized; see [link to relevant documentation]. Figure 2 and Figure 3The piezoelectric drive assembly 140 includes at least one set of piezoelectric ceramics. The number of piezoelectric ceramics assembled is determined according to the actual force requirements, and is generally an even number. Two piezoelectric ceramic pieces 142 form a group, and the two piezoelectric ceramic pieces 142 are configured to extend in opposite directions under the driving voltage to jointly push or pull the drive frame 141. This "push-pull" working mode allows them to jointly push or pull the drive frame 141, thereby outputting a larger driving force and a more stable displacement, effectively overcoming the shortcomings of the traditional single piezoelectric piece driving force, and providing a power basis for a wide range of thrust output.

[0099] In one example, the armature assembly 130 is detailed. For example... Figure 3 and Figure 4 As shown, the armature assembly 130 includes a leaf spring 133. The leaf spring 133 is configured to center the armature assembly 130 and provide initial sealing force. Its periphery is fixed, and its central portion is connected to the armature 131. Through its elastic deformation, on the one hand, it constrains the armature 131 to make precise linear movements only along the axial direction, preventing radial sway; on the other hand, its pre-tightening force ensures that the valve needle 132 can be stably pressed into the flow channel hole of the sealing module 180 when it is in the zero position, achieving a reliable normally closed seal.

[0100] In one example, the pressure cap 143 is screwed to the tail of the armature assembly 130 and pressed against the piezoelectric drive assembly 140 by the force applied by the disc spring 144. As the part directly connecting the armature assembly 130 and the piezoelectric drive assembly 140, the disc spring 144 fixes and adjusts the height of the armature assembly 130 to achieve valve opening and closing. The disc spring 144 is pre-compressed between the housing 150 of the piezoelectric proportional valve and the pressure cap 143 to provide and maintain a constant axial mechanical preload. This preload effectively eliminates backlash in the transmission chain, ensuring hysteresis-free and continuous bidirectional displacement transmission of the piezoelectric actuator, while protecting the piezoelectric ceramic 142 from tensile stress impacts and compensating for component deformation in a wide temperature range, maintaining the stability and reliability of thrust control.

[0101] See one example. Figure 4 The armature assembly 130 also includes an armature 131 and a valve needle 132 disposed at its front end. The armature 131 has an axial airflow channel inside, and the front end of the channel has a plurality of radial air holes 1311 in the circumferential direction.

[0102] The module also includes a support assembly 160, which is fixedly connected to the housing 150 of the piezoelectric proportional valve. The support assembly 160 includes an upper support block 161 and a lower support block 162. The upper support block 161 has an upper through hole through which the armature 131 passes and fits against its outer wall, serving as an auxiliary guide. The lower support block 162 has a lower through hole with a diameter larger than the outer diameter of the armature 131, so that there is an annular gap between the armature 131 passing through this hole and the lower through hole, forming an airflow buffer chamber 163. A leaf spring 133 is pressed between the upper support block 161 and the lower support block 162. The armature 131 passes through the upper through hole and the lower through hole in sequence, and the valve needle 132 is inserted into the flow channel hole of the sealing module 180. High-pressure gas flows in from the inlet, passes through the airflow channel inside the armature 131, is ejected from the circumferential air hole 1311 at its front end, enters the airflow buffer chamber 163 for pressure stabilization, and then enters the flow channel hole of the sealing module 180. This design allows for a more stable and uniform airflow before throttling, which helps improve thrust stability.

[0103] See one example. Figure 3 and Figure 4 The support assembly 160 is connected to the housing 150 of the piezoelectric proportional valve via a dedicated base 170. The base 170 is a hollow cylinder with an outwardly extending annular stop at its lower end. The outer periphery of the hollow cylinder is tightly fitted against the inner wall of the housing 150 of the piezoelectric proportional valve, while the annular stop is located outside the housing 150 and abuts against the lower end of the housing, achieving axial positioning.

[0104] The support assembly 160 is fixedly mounted within the hollow cylinder of the base 170. The sealing module 180 and the nozzle throat throttling unit 200 are also sequentially mounted within the hollow cylinder of the base 170. The sealing module 180, located between the support assembly 160 and the nozzle throat throttling unit 200, includes a sealing pressure block 181 and a sealing block 182. The sealing block 182 presses against the nozzle throat throttling unit 200, and the sealing pressure block 181 is located between the support assembly 160 and the sealing block 182. The sealing pressure block 181 has a valve needle through-hole, which communicates with the airflow buffer chamber 163. The valve needle 132 passes through the through-hole of the sealing pressure block 181 and the sealing block 182 in sequence, and then inserts into the flow channel hole of the sealing block 182. This integrated design ensures the coaxiality and airtightness between the components, providing a structural guarantee for achieving high-precision control.

[0105] Based on any of the above examples, see Figure 3 The valve core position sensor 500 operates based on the principle of capacitance change or the Wheatstone bridge principle. Its sensing head 502 is fixed to the bellows 120 or the armature assembly 130 to follow the movement of the armature assembly; its circuit board 501 is fixed to the valve body, thereby accurately measuring the micro-displacement of the valve core in a non-contact manner.

[0106] In one example, such as Figure 5As shown, the flow sensor 400 includes a flow channel 401 and a MEMS chip (integrated on a circuit board 402). Non-metallic support plates 403 are mounted on both sides of the flow channel 401. The non-metallic support plates 403 contact the inner wall of the housing assembly 600 and are fixed by metal rings 404, thereby greatly enhancing the impact and vibration resistance of the flow channel and the sensor as a whole. The non-metallic support plates 403 have a lower hardness than metal, giving them impact and vibration resistance. In one example, to improve the stability of the mounting connection while enhancing impact and vibration resistance, the outer periphery of the non-metallic support plate 403 has a groove, and a metal ring 404 is placed in the groove. This facilitates screw connection and greatly enhances the impact and vibration resistance of the flow channel and the sensor as a whole.

[0107] See Figure 1 In one example, the housing assembly 600 includes a cylindrical housing 601, a top cover 602, and a bottom cover 603. The cylindrical housing 601 is preferably a one-piece titanium alloy housing. The top cover 602 and bottom cover 603 are connected to the cylindrical housing 601 by welding or screws, forming a high-strength, sealed space that provides excellent electromagnetic shielding. All internal cables 900 of the module are processed using a twisted-pair and shielded process, and all electrical signals are uniformly output through no more than two electrical connectors 800 on the top cover 602. All components and circuits are encapsulated in a cylindrical armor, and electrical signals are uniformly output through two electrical connectors. All lines that may be subject to interference are shielded and twisted-paired, providing on-orbit resistance to strong electromagnetic interference and greatly reducing the points of electromagnetic interference introduction. The module controller is preferably an external propulsion system circuit box, connected to the module via electrical connectors 800, facilitating upgrades and maintenance.

[0108] One end of the module inlet 700 is connected to the flow sensor 400, and the other end extends out of the upper cover 602 for connecting the module to other components.

[0109] This embodiment provides specific configurations for four operating modes of the module controller. The module controller is programmed to execute at least one of the following operating modes:

[0110] Open-loop operating mode: The controller receives the thrust command, directly calculates the corresponding drive voltage U based on the preset thrust-drive voltage mapping relationship (obtained through ground calibration), and outputs it to the piezoelectric proportional valve 100. This mode does not rely on real-time feedback from sensors, has the fastest response, and is used for rapid, coarse thrust adjustment.

[0111] See Figure 7 Flow closed-loop operating mode: The controller receives thrust commands. F com And convert it into the target flow signal value. G comThen, the flow signal fed back in real time by the flow sensor 400. G m To achieve the control objective, the drive voltage U is dynamically adjusted using flow closed-loop control algorithms such as PID control, thereby adjusting the actual flow signal. G m Converging to the target flow signal value G com This ensures thrust accuracy.

[0112] See Figure 7 Displacement closed-loop operating mode: The controller receives thrust commands. F com This is then converted into the target valve spool displacement value, and then the valve spool position signal fed back in real time by the valve spool position sensor 500 is used. G n To achieve the control objective, the drive voltage U is adjusted using a displacement closed-loop control algorithm to control the valve core position signal generated by the actual displacement x of valve needle 132. G n It converges to the target displacement value. This mode has a fast response speed and is suitable for highly dynamic scenarios.

[0113] See Figure 7 Displacement and flow rate dual closed-loop operating mode: The controller receives thrust commands. F com First, based on the feedback signal from the valve core position sensor 500 G n Fast coarse closed-loop control of line displacement ensures millisecond-level response speed; and the flow signal fed back from the flow sensor 400. G m To achieve the ultimate control objective, a precise closed-loop flow control is implemented to output the actual flow rate. With actual thrust This ensures output accuracy at the 0.1μN level. This mode is the optimal mode that balances response speed and control precision.

[0114] This embodiment provides a multi-mode cooperative control method for any of the above-mentioned piezoelectric-cooled gas-driven variable thrust modules. See also Figure 7 As shown in the control block diagram, the method includes the following steps:

[0115] Steps for receiving thrust commands: The module controller receives thrust commands from the host computer. F com .

[0116] Operating mode decision and execution steps: The module controller determines the operating mode based on the thrust command. F com The size of the valve automatically selects and executes the corresponding control mode to drive the piezoelectric proportional valve 100. Its decision logic is as follows:

[0117] When rapid, coarse thrust adjustment is required (such as rapid attitude stabilization after a wide range of maneuvers), an open-loop operating mode is adopted.

[0118] When thrust command F com The corresponding thrust value is less than 10 2 When the thrust resolution is ≤0.1μN and the response time is <50 ms (e.g., without the ultra-precise adjustment required for drag control), a displacement closed-loop working mode or a displacement-flow dual closed-loop working mode is adopted. The former uses the feedback signal from the valve core position sensor. G n To achieve rapid and precise control of the target; the latter firstly... G n The signal undergoes rapid displacement and coarse closed-loop processing, and then a feedback signal is generated from the flow sensor. G m To achieve precise closed-loop traffic management.

[0119] When thrust command F com The corresponding thrust value is 10 2 μN to 10 3 When the thrust resolution is required to be ≤1μN and the response time <250 ms (e.g., during routine attitude adjustment), either the flow closed-loop operating mode or the displacement-flow dual closed-loop operating mode is adopted. The former uses the feedback signal from the flow sensor. G m To achieve stable control for the target.

[0120] Through the above-mentioned adaptability control of working modes and thrust range, the module can achieve a thrust range of 10 -2 μN to 10 3 Within a thrust range of μN, a thrust of less than 10 is stably achieved. 2 At a resolution ≤ 0.1 μN and a response time < 50 ms, the thrust is 10. 2 μN to 10 3 Excellent performance output with resolution ≤1 μN and response time <250 ms at μN.

[0121] In summary, the piezoelectric cold gas variable thrust module of this embodiment, based on the bidirectional output of the piezoelectric actuator and the structural design of the armature assembly valve needle and nozzle throat throttling unit, achieves a wide range of thrust output, covering 10 for the first time. -2 ~10 3 On the order of μN. Based on the design of the piezoelectric proportional valve and the throttling unit in the nozzle throat, closed-loop control is achieved by collecting temperature, flow rate, and valve core position signals. The piezoelectric proportional valve actuator is controlled through a cold-push circuit box, achieving a flow rate of less than μN for the first time. 2 Resolution less than or equal to 0.1 μN in the μN range, 102 ~10 3 The resolution is less than or equal to 1 μN within the μN range.

[0122] During module operation, the module controller, through the acquisition of flow and displacement signals, outputs a piezoelectric valve drive voltage to adjust the thrust throat area, thereby achieving thrust regulation. The variable thrust regulation modes include four types: open-loop mode, flow closed-loop mode, displacement closed-loop mode, and flow-displacement dual closed-loop mode. The control logic switches according to different scenarios, achieving a thrust of less than 10 for the first time. 2 Response time less than 50ms in the μN range; 10 2 ~10 3 The response time is less than 250ms within the μN range. By calibrating the inverse piezoelectric effect of the piezoelectric proportional valve and the flow sensor over a wide temperature range, on-orbit wide-temperature-range environmental performance compensation is achieved, ensuring the thrust output range and accuracy.

[0123] Any aspects of this invention not described in detail are common knowledge or prior art in the field.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that not every embodiment contains only one independent technical solution, and in the absence of conflict between solutions, the various technical features mentioned in each embodiment can be combined in any way to form other implementation methods that can be understood by those skilled in the art.

[0125] Furthermore, without departing from the scope of the present invention, modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, shall not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wide-range, high-precision piezoelectric-cooled gas-driven thrust module, characterized in that, include: A piezoelectric proportional valve includes an inlet connector, a bellows, an armature assembly, and a piezoelectric drive assembly. The bellows is used to achieve an elastic connection between the inlet connector and the armature assembly. The piezoelectric drive assembly is used to provide a driving force to drive the armature assembly to move axially. The armature assembly cooperates with the valve port through axial movement to control the flow channel opening. The nozzle throat throttling unit, which is a micro-Newton Laval nozzle, cooperates with the valve needle of the armature assembly to adjust the thrust by changing the throat throttling area; The sensor group includes a temperature sensor for collecting the temperature at various points on the module, a flow sensor for providing the module's flow rate signal, and a valve core position sensor for providing the valve core position signal. The housing assembly encapsulates the piezoelectric proportional valve, the nozzle throat throttling unit, and the sensor assembly within it; A module controller, electrically connected to the sensor group and the piezoelectric proportional valve, is configured to selectively control the piezoelectric proportional valve in open-loop operation mode, flow closed-loop operation mode, displacement closed-loop operation mode, or displacement-flow dual closed-loop operation mode based on thrust commands and sensor signals. Through the multi-mode selective control of the module controller, the module can achieve [a certain operation] within 10 [units of time / time]. -2 μN to 10 3 Achieve high-precision and fast-response thrust output within a thrust range of μN; The armature assembly includes a leaf spring, which is configured to center the armature assembly and provide a sealing force, so that the valve needle moves stably in the flow channel hole of the sealing module and achieves a seal. The armature assembly also includes an armature and a valve pin disposed at the front end of the armature. The armature has an airflow channel, and the front end of the airflow channel has multiple air holes in the circumferential direction. The piezoelectric air-cooled thrust converter module also includes a support assembly, which is fixedly connected to the housing of the piezoelectric proportional valve. The support assembly includes an upper support block and a lower support block. The upper support block has an upper through hole for the armature to pass through and fit against the armature. The lower support block has a lower through hole with a diameter larger than the outer diameter of the armature, so that there is a gap between the armature passing through the lower support block and the lower through hole, forming an airflow buffer chamber. The leaf spring is disposed between the upper support block and the lower support block. The armature passes through the upper through hole and the lower through hole. The valve needle is inserted into the flow channel hole of the sealing module. The air hole communicates with the airflow buffer chamber and the flow channel hole of the sealing module. The open-loop operating mode is configured as follows: the module controller receives the thrust command, directly calculates the corresponding drive voltage based on the preset thrust-drive voltage mapping relationship, and outputs it to the piezoelectric proportional valve; The flow closed-loop working mode is configured as follows: the module controller receives the thrust command and converts it into a target flow value. Then, taking the flow signal fed back by the flow sensor in real time as the control target, the controller adjusts the drive voltage output to the piezoelectric proportional valve through the flow closed-loop control algorithm so that the actual flow converges to the target flow value. The displacement closed-loop working mode is configured as follows: the module controller receives the thrust command and converts it into a target valve core displacement value. Then, taking the valve core position signal fed back by the valve core position sensor in real time as the control target, the drive voltage output to the piezoelectric proportional valve is adjusted through the displacement closed-loop control algorithm so that the actual valve core displacement converges to the target valve core displacement value. The displacement-flow dual closed-loop operating mode is configured such that the module controller first performs coarse closed-loop displacement control using the feedback signal from the valve core position sensor, and then performs precise closed-loop flow control using the feedback signal from the flow sensor.

2. The piezoelectric gas-cooled variable thrust module according to claim 1, characterized in that: The piezoelectric drive assembly includes at least one set of piezoelectric ceramics, each set of piezoelectric ceramics comprising two piezoelectric ceramic plates configured to extend in opposite directions under a drive voltage to jointly push or pull the drive frame.

3. The piezoelectric gas-cooled variable thrust module according to claim 1, characterized in that: The support assembly is connected to the housing of the piezoelectric proportional valve via a base. The base includes a hollow column and an annular stop block disposed at the lower end of the hollow column. The outer periphery of the hollow column is attached to the inner wall of the housing of the piezoelectric proportional valve. The annular stop block is located outside the housing of the piezoelectric proportional valve and abuts against the lower end of the housing of the piezoelectric proportional valve. The support assembly is fixedly disposed within the hollow cylinder. The sealing module and the nozzle throat throttling unit are disposed within the hollow cylinder. The sealing module is located between the support assembly and the nozzle throat throttling unit. The sealing module includes a sealing pressure block and a sealing block. The sealing block is pressed against the nozzle throat throttling unit. The sealing pressure block is located between the support assembly and the sealing block. The sealing pressure block is provided with a valve needle through hole. The valve needle through hole communicates with the airflow buffer chamber. The valve needle passes through the sealing block and is inserted into the flow channel hole of the sealing block.

4. The piezoelectric gas-cooled variable thrust module according to claim 1, characterized in that: The valve core position sensor operates based on the principle of capacitance change or the Wheatstone bridge principle. Its sensing head is fixed to the bellows or armature assembly to follow the movement of the armature assembly.

5. The piezoelectric gas-cooled thrust converter module according to claim 1, characterized in that: The flow sensor includes a flow channel and a MEMS chip, and non-metallic support plates are installed on both sides of the flow channel. The non-metallic support plates are in contact with the housing assembly to enhance impact and vibration resistance.

6. The piezoelectric gas-cooled variable thrust module according to claim 1, characterized in that: The outer casing assembly includes a cylindrical outer casing, a top cover, and a bottom cover. The cylindrical outer casing is a one-piece molded titanium alloy casing. The top cover and bottom cover are respectively connected to the cylindrical outer casing to form a sealed space; or The internal cables of the piezoelectric air-cooled thrust converter module are all processed using a twisted-pair shielding technique, and all electrical signals are output uniformly through no more than two electrical connectors; or The module controller is an external propulsion system circuit box.

7. A multi-mode cooperative control method for the piezoelectric cold gas variable thrust module according to any one of claims 1 to 6, characterized in that, The method includes the following steps: Steps for receiving thrust commands: The module controller receives thrust commands from the host computer; Operating mode decision and execution steps: Based on the magnitude of the thrust command and / or the requirements for dynamic performance of thrust changes, select and execute the corresponding control operating mode to drive the piezoelectric proportional valve, wherein: When rapid and coarse thrust adjustment is required, an open-loop operating mode is adopted: the module controller directly outputs the drive voltage based on a preset thrust-drive voltage mapping relationship; When the thrust value corresponding to the thrust command is less than 10 2 When the thrust resolution is required to be ≤0.1μN and the response time is <50 ms, a displacement closed-loop working mode or a displacement-flow dual closed-loop working mode is adopted. The displacement closed-loop working mode uses the feedback signal of the valve core position sensor as the target for precise control. The displacement-flow dual closed-loop working mode first uses the feedback signal of the valve core position sensor to perform rapid displacement coarse closed loop, and then uses the feedback signal of the flow sensor to perform precise flow closed loop. When the thrust value corresponding to the thrust command is 10 2 μN to 10 3 Within the μN range, and with a thrust resolution ≤1μN and a response time <250 ms required, a flow closed-loop working mode or a displacement-flow dual closed-loop working mode is adopted; the flow closed-loop working mode uses the feedback signal of the flow sensor as the target for stable control. Through the adaptive control of the operating mode and thrust range, the module can achieve a thrust range of 10... -2 μN to 10 3 Within a thrust range of μN, achieve a thrust of less than 10. 2 At a resolution ≤ 0.1 μN and a response time < 50 ms, the thrust is 10 μN. 2 μN to 10 3 Performance output with resolution ≤1μN and response time <250 ms at μN.

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