A spaceborne active phased array antenna thermal control device and method

Abstract

The application relates to a satellite-borne active phased array antenna thermal control device and method, which comprises an antenna assembly, a main active thermal control assembly, a satellite platform and a controller. The antenna assembly comprises, in sequence, an antenna cover, an antenna subarray, a thermal control structure, a phase change heat storage module and an antenna bottom plate. The thermal control structure comprises a first working medium inlet and a first working medium outlet. The phase change heat storage module comprises a second working medium inlet and a second working medium outlet. The phase change heat storage module is provided with a thermochromic intelligent coating on the periphery. The main active thermal control assembly comprises a liquid storage tank, a driving pump, a valve, a flow meter, a pressure gauge, a temperature sensor and the controller. The antenna assembly is installed on the satellite platform through the antenna bottom plate, and the main active thermal control assembly is arranged in the satellite platform. The application can automatically complete closed-loop temperature control according to the real-time high and low temperatures of the antenna, is especially suitable for high heat flux density satellite-borne active phased array antennas, and is integrally designed with the antenna structure, so that the thermal control function meets the thermal control demand and has the advantages of light weight.

Description

Technical Field

[0001] This invention relates to the field of aerospace technology, specifically to a thermal control device and method for a spaceborne active phased array antenna. Background Technology

[0002] Active phased array antennas, with their advantages of flexible and controllable beam pointing and high reliability, have become an important trend in future antenna development. As the payload of satellites, spaceborne active phased array antennas operate in an extremely harsh space thermal environment. They are affected not only by external space heat fluxes such as direct solar radiation, Earth's albedo radiation, and Earth's infrared radiation, but also by near-4K low temperatures and frequent transitions between Earth's illuminated and shadowed zones, resulting in drastic temperature changes. Furthermore, the increased integration and performance of antennas lead to denser placement of high-power components, resulting in high instantaneous heat dissipation, concentrated heat, and high local heat flux density, making heat dissipation difficult. Inadequate thermal control measures will severely affect the normal operation of the antenna in orbit.

[0003] Typically, spaceborne phased array antennas employ heat pipe-based thermal control methods, which include heat pipes, radiating heat sinks, electric heaters, thermal control coatings, and multi-layered thermal insulation components. However, heat pipe-based thermal control methods are only suitable for low heat flux densities (<10 W / cm³). 2 In applications where spaceborne millimeter-wave active phased array antennas are used, their typical characteristic is high-density integration. For example, taking the Ka-band at 30 GHz as an example, the element spacing (approximately half a wavelength) is only 5 mm. Integrating high-power active devices such as power amplifiers and low-noise amplifiers in such a small space, the heat flux density will easily exceed 10 W / cm². 2 Therefore, other more effective thermal control methods are needed to ensure that the antenna is kept at a reasonable temperature level. Summary of the Invention

[0004] In view of this, the present invention aims to propose a thermal control device and method for a spaceborne active phased array antenna, which solves the problem that current thermal control methods cannot be applied to scenarios with high heat flux density.

[0005] In a first aspect, a first embodiment of the present invention provides a spaceborne active phased array antenna thermal control device, comprising: an antenna assembly including an antenna radome, an antenna subarray, a thermal control structure, a phase change thermal storage module, and an antenna base plate arranged sequentially; the thermal control structure including a first working fluid inlet and a first working fluid outlet; the phase change thermal storage module including a second working fluid inlet and a second working fluid outlet; and a thermochromic smart coating disposed on the outer periphery of the phase change thermal storage module; and an active thermal control component including a storage tank, a drive pump, a valve, a flow meter, a pressure gauge, at least one temperature sensor, and a controller; the controller being connected to the drive pump and the temperature sensor; and the temperature sensor being connected to the antenna assembly; the thermal control working fluid stored in the storage tank is circulated sequentially through the drive pump, the valve, the flow meter, the pressure gauge, the first working fluid inlet, the first working fluid outlet, the second working fluid inlet, and the second working fluid outlet back to the storage tank to form a flow loop.

[0006] Furthermore, the antenna subarray is disposed on the thermal control structure, the phase change thermal storage module is connected to the lower surface of the thermal control structure, and the antenna base plate is connected to the lower surface of the phase change thermal storage module; wherein, the phase change thermal storage module is a frame body, forming a hollow region between the thermal control structure and the antenna base plate, in the hollow region, the first working fluid inlet is connected to the output pipeline of the active thermal control component, the first working fluid outlet is connected to the second working fluid inlet through a pipeline, the second working fluid outlet is connected to the input pipeline of the active thermal control component, and the antenna base plate has through holes for each pipeline to pass through.

[0007] Furthermore, the antenna assembly is mounted on the satellite platform via the antenna base plate, and the active thermal control assembly is located within the satellite platform.

[0008] Furthermore, the thermal control structure has multiple parallel fluid channels connecting the first inlet of the working fluid and the first outlet of the working fluid.

[0009] Furthermore, the phase change thermal storage module includes a phase change material layer and a fluid layer, with the second inlet and the second outlet of the working fluid both located in the fluid layer.

[0010] Furthermore, the thermochromic smart coating is disposed on the outer periphery of the phase change material layer, and a multilayer heat insulation component is disposed on the outer periphery of the fluid layer.

[0011] Furthermore, the outer periphery of both the thermal control structure and the antenna base plate is provided with multi-layer heat insulation components, and the thermal control structure, the phase change heat storage module and the antenna base plate are all non-thermally conductive connections.

[0012] Furthermore, the thermal control structure includes multiple thermal control structure lattice cells, and the phase change thermal storage module includes multiple phase change thermal storage module lattice cells. The thermal control structure lattice cells and the phase change thermal storage module lattice cells are tetrahedral, pyramidal, or Kagome-type lattice cells.

[0013] Furthermore, the phase change thermal storage module is also provided with a phase change material injection port.

[0014] In a second aspect, a second embodiment of the present invention provides a thermal control method for a spaceborne active phased array antenna, utilizing a spaceborne active phased array antenna thermal control device as described in any of the first aspects. The method includes: the temperature sensor monitoring the temperature of the antenna subarray; when the temperature of the antenna subarray is greater than a threshold, the controller controls the drive pump to drive the thermal control working fluid in the storage tank to circulate through the flow loop, wherein the thermal control working fluid absorbs heat from the antenna subarray during circulation, and the thermal control working fluid transfers heat to the phase change material in the phased heat storage module when passing through the phased heat storage module, with a portion of the heat stored by the phase change material and another portion of the heat dissipated through the thermochromic smart coating; when the temperature of the antenna subarray is less than the threshold, the controller controls the drive pump to drive the thermal control working fluid in the storage tank to circulate through the flow loop, wherein when the thermal control working fluid passes through the phased heat storage module, at least a portion of the heat stored by the phase change material in the phased heat storage module is transferred to the thermal control working fluid, which then carries the heat to the antenna subarray during circulation.

[0015] This invention employs a combined active and passive thermal control method using a pump-driven fluid circuit, a phase-change thermal storage module, and a thermochromic coating. This method is applicable to high heat flux density heat dissipation scenarios, and is particularly suitable for spaceborne antennas (where heat flux density is typically >10 W / cm²). 2 This not only eliminates the need for a power compensation electric heating device, but also allows for radiative heat dissipation using the antenna's own structure, eliminating the need for an additional radiative heat sink.

[0016] This invention adopts an integrated design of antenna structure and thermal control. Both the thermal control structure and the phase change thermal storage module adopt a three-dimensional dot matrix structure, which achieves lightweighting while ensuring thermal control and load-bearing capacity.

[0017] This invention is simple and practical; it only requires the satellite platform to provide an interface for active thermal control to complete its own thermal control closed loop. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the thermal control device for a spaceborne active phased array antenna according to an embodiment of the present invention.

[0020] Figure 2 This is a top-view perspective three-dimensional schematic diagram of the antenna assembly according to an embodiment of the present invention;

[0021] Figure 3 This is a three-dimensional schematic diagram of the antenna assembly from a bottom-view perspective according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the flow path of the thermal control working fluid in an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the flow channel of the thermal control working fluid within the thermal control structure according to an embodiment of the present invention;

[0024] Figure 6 This is a partial three-dimensional schematic diagram of the phase change thermal energy storage module according to an embodiment of the present invention;

[0025] Figure 7 This is a partial front view of the phase change thermal energy storage module according to an embodiment of the present invention. Detailed Implementation

[0026] The description of the embodiments in this specification should be taken in conjunction with the accompanying drawings, which should form part of the complete specification. In the drawings, the shape or thickness of the embodiments may be exaggerated and may be indicated in a simplified or convenient manner. Furthermore, parts of the various structures in the drawings will be described separately; it is worth noting that elements not shown in the figures or not described in words are in a form known to those skilled in the art.

[0027] The descriptions of the embodiments herein, including any references to directions and orientations, are for ease of description only and should not be construed as limiting the scope of the invention. The following description of preferred embodiments involves combinations of features, which may exist independently or in combination; the invention is not particularly limited to the preferred embodiments. The scope of the invention is defined by the claims.

[0028] like Figure 1As shown, the thermal control device for a spaceborne active phased array antenna in the first embodiment of the present invention includes a controlled antenna assembly 1 and an active thermal control assembly 2. The active thermal control assembly 2 is a pump-driven fluid circuit, including a liquid storage tank 2-1, a drive pump 2-2, a valve 2-3, a flow meter 2-4, a pressure gauge 2-5, a temperature sensor 2-6, and a controller 2-7.

[0029] like Figure 2 and Figure 3 As shown, antenna assembly 1 includes an radome 1-1, an antenna subarray 1-2, a thermal control structure 1-3, a phase change thermal storage module 1-4, an antenna base plate 1-5, and a thermochromic coating 1-6. The thermal control structure 1-3 includes a first working fluid inlet 1-3-1 and a first working fluid outlet 1-3-2, and the phase change thermal storage module 1-4 includes a second working fluid inlet 1-4-1 and a second working fluid outlet 1-4-2.

[0030] like Figure 4 and Figure 5 As shown, the first working fluid outlet 1-3-2 and the second working fluid inlet 1-4-1 of the antenna assembly 1 are connected by a pipeline (not shown). The first working fluid inlet 1-3-1 and the first working fluid outlet 1-3-2 in the thermal control structure 1-3 are a multi-channel parallel structure.

[0031] In this embodiment, antenna assembly 1 is mounted on satellite platform 3 via antenna base plate 1-5. Active thermal control assembly 2 is located within satellite platform 3. Active thermal control assembly 2 uses drive pump 2-2 as a node. One side of the pump is sequentially connected to valve 2-3, flow meter 2-4, and pressure gauge 2-5, and is connected to the first working fluid inlet 1-3-1 of antenna assembly 1 via an output pipeline. The other side of the pump is connected to storage tank 2-1, and is connected to the second working fluid outlet 1-4-2 of antenna assembly 1 via an input pipeline, thus forming a fluid loop for the flow of thermal control working fluid within storage tank 2-1. Multiple temperature sensors 2-6 are respectively deployed at different locations on antenna assembly 1, and then uniformly connected to controller 2-7, which in turn is connected to drive pump 2-2.

[0032] like Figure 6 and Figure 7 As shown, the phase change thermal storage module 1-4 has a double-layer structure, with the upper layer being a phase change material layer 1-4-5 and the lower layer being a fluid layer 1-4-6. The phase change material layer 1-4-5 contains a lattice-structured, heat-conducting matrix and is filled with phase change material, which is injected through the phase change material inlet 1-4-3. The phase change thermal storage module 1-4 serves not only for heat storage and dissipation but also for structural support.

[0033] like Figure 3As shown, the phase change thermal storage module 1-4 is a frame, such as a rectangular frame, forming a hollow area between the thermal control structure 1-3 and the antenna base plate 1-5. Within this hollow area, the first working fluid inlet 1-3-1 is connected to the output pipeline (pipeline not shown) of the active thermal control component 2; the first working fluid outlet 1-3-2 is connected to the second working fluid inlet 1-4-1 via a pipeline (pipeline not shown); and the second working fluid outlet 1-4-2 is connected to the input pipeline (pipeline not shown) of the active thermal control component 2. To allow these pipelines to pass through, the antenna base plate 1-5 has through holes (through holes not shown) for each pipeline to pass through.

[0034] like Figures 1-7 As shown, the thermal control method for a spaceborne active phased array antenna in the second embodiment of the present invention is implemented based on the device of the first embodiment, and can realize heat dissipation and heat preservation of the phased array antenna. Multiple temperature sensors 2-6 distributed at different positions of the antenna assembly 1 transmit the measured temperature signals to the controller 2-7 in real time. The controller 2-7 continuously compares the monitored temperature with the preset upper and lower temperature thresholds.

[0035] When antenna assembly 1 is powered on in orbit, the irradiation of external heat flow and the heat generated by the high-power-density T / R components in antenna subarray 1-2 cause the temperature of antenna assembly 1 to rise. When controller 2-7 detects that the temperature exceeds the preset upper limit threshold, controller 2-7 generates a control signal and transmits it to drive pump 2-2 to start drive pump 2-2. Drive pump 2-2 drives the thermal control working fluid in storage tank 2-1 to flow through valve 2-3, flow meter 2-4 and pressure gauge 2-5 in sequence, and enters the interior of antenna assembly 1 through the first working fluid inlet 1-3-1. It then passes through multiple parallel fluid channels inside thermal control structure 1-3, the first working fluid outlet 1-3-2, the second working fluid inlet 1-4-1, the fluid layer 1-4-6 of phase change thermal storage module 1-4, and the second working fluid outlet 1-4-2 to the storage tank 2-1 to form a closed flow loop, carrying away the heat generated by the T / R components in antenna subarray 1-2. When the thermal control working fluid enters the phase change thermal storage module 1-4 and flows in the fluid layer 1-4-6, it transfers heat to the phase change material layer 1-4-5. After absorbing heat, the phase change material layer 1-4-5 undergoes a phase change, followed by a temperature increase. Because the phase change material layer 1-4-5 is coated with a thermochromic smart coating 1-6, which utilizes the characteristic that the infrared hemispherical emissivity of the thermochromic smart coating 1-6 increases with temperature, heat is radiated to the space environment through the thermochromic smart coating 1-6, achieving heat dissipation. When the temperature of the phase change material layer 1-4-5 decreases to a certain value due to heat dissipation, it achieves a dynamic thermal equilibrium with the space environment, thereby storing some heat inside the phase change material layer 1-4-5. The thermal control working fluid continuously circulates in the flow loop. When the temperature of the antenna subarray 1-2 drops below the upper temperature threshold, the controller 2-7 controls the drive pump 2-2 to stop working.

[0036] When antenna assembly 1 is powered off and in the Earth's shadow, and its temperature is below the preset lower limit threshold, controller 2-7 activates drive pump 2-2. As the thermal control fluid flows through phase change thermal storage module 1-4, it absorbs heat from phase change material layer 1-4-5. This heat is then transferred to antenna subarray 1-2 as it circulates, thus compensating for the temperature of antenna subarray 1-2 and preventing it from becoming too cold. Once the temperature of antenna subarray 1-2 rises above the lower limit threshold, controller 2-7 stops drive pump 2-2.

[0037] like Figures 5-7 As shown, in this embodiment, both the thermal control structure 1-3 and the phase change thermal storage module 1-4 are integrally formed using additive manufacturing. The thermal control structure 1-3 includes several thermal control structure lattice cells 1-3-3, and the phase change material layer 1-4-5 of the phase change thermal storage module 1-4 includes several phase change thermal storage module lattice cells 1-4-4. These lattice cells can be tetrahedral, pyramidal, or Kagome-type. Thus, while ensuring thermal control and load-bearing capacity, lightweight design is also achieved.

[0038] In this embodiment, the phase change thermal storage module 1-4 is connected to the thermal control structure 1-3 and the antenna base plate 1-5 via thermal insulation pads for non-thermal connection. The fluid layer 1-4-6 of the thermal control structure 1-3, the phase change thermal storage module 1-4, and the antenna base plate 1-5 are all covered with multi-layer thermal insulation components to suppress heat exchange with the space environment.

[0039] Optionally, the thermochromic smart coatings 1-6 can be lanthanum manganate (La1-xCaxMnO3 and La1-xSrxMnO3) complexes doped with strontium and calcium.

[0040] In this embodiment, the preset upper / lower temperature thresholds of controllers 2-7 are generally 5-10°C lower than or higher than the highest / lowest allowable temperature values ​​of antenna subarrays 1-2.

[0041] In summary, this invention: (1) employs a pump-driven fluid circuit, a phase change thermal storage module, and a thermochromic coating active-passive composite thermal control method, which is applicable to spaceborne antennas with higher heat flux densities (heat flux density > 10 W / cm²). 2 (1) It not only eliminates the need for power compensation electric heating device, but also completes radiation heat dissipation using the antenna's own structure, without the need for an additional radiation heat sink; (2) The antenna structure is designed with integrated thermal control. The thermal control structure and phase change heat storage module both adopt a three-dimensional dot matrix structure, which ensures thermal control and support load-bearing while also achieving lightweighting; (3) The thermal control device is simple and practical. The antenna only needs the satellite platform to provide an interface for active thermal control to complete its own thermal control closed loop.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thermal control device for a spaceborne active phased array antenna, characterized in that, include: The antenna assembly (1) includes an antenna radome (1-1), an antenna subarray (1-2), a thermal control structure (1-3), a phase change thermal storage module (1-4), and an antenna base plate (1-5) arranged sequentially. The thermal control structure (1-3) includes a first working fluid inlet (1-3-1) and a first working fluid outlet (1-3-2). The phase change thermal storage module (1-4) includes a second working fluid inlet (1-4-1) and a second working fluid outlet (1-4-2). The phase change thermal storage module (1-4) is provided with a thermochromic smart coating (1-6) on its outer periphery. The phase change thermal storage module (1-4) includes a phase change material layer (1-4-5) and a fluid layer (1-4-6), with the second working fluid inlet (1-4-1) and the second working fluid outlet (1-4-2) both located in the fluid layer (1-4-6). The thermochromic smart coating (1-6) is disposed on the outer periphery of the phase change material layer (1-4-5), and a multi-layer heat insulation component is disposed on the outer periphery of the fluid layer (1-4-6); The outer periphery of the thermal control structure (1-3) and the antenna base plate (1-5) are provided with multi-layer heat insulation components, and the thermal control structure (1-3), the phase change heat storage module (1-4) and the antenna base plate (1-5) are all non-thermally conductive connections. The thermal control structure (1-3) includes multiple thermal control structure lattice cells (1-3-3), and the phase change thermal storage module (1-4) includes multiple phase change thermal storage module lattice cells (1-4-4). The thermal control structure lattice cells (1-3-3) and the phase change thermal storage module lattice cells (1-4-4) are tetrahedral, pyramidal, or Kagome-type lattice cells. The active thermal control assembly (2) includes a liquid storage tank (2-1), a drive pump (2-2), a valve (2-3), a flow meter (2-4), a pressure gauge (2-5), at least one temperature sensor (2-6), and a controller (2-7). The controller (2-7) is connected to the drive pump (2-2) and the temperature sensor (2-6). The temperature sensor (2-6) is connected to the antenna assembly (1). The thermal control working fluid stored in the storage tank (2-1) is sequentially circulated back to the storage tank (2-1) via the drive pump (2-2), the valve (2-3), the flow meter (2-4), the pressure gauge (2-5), the first working fluid inlet (1-3-1), the first working fluid outlet (1-3-2), the second working fluid inlet (1-4-1), and the second working fluid outlet (1-4-2) to form a flow loop.

2. The thermal control device for a spaceborne active phased array antenna according to claim 1, characterized in that, The antenna subarray (1-2) is disposed on the thermal control structure (1-3), the phase change thermal storage module (1-4) is connected to the lower surface of the thermal control structure (1-3), and the antenna base plate (1-5) is connected to the lower surface of the phase change thermal storage module (1-4). The phase change thermal storage module (1-4) is a frame structure, forming a hollow area between the thermal control structure (1-3) and the antenna base plate (1-5). In the hollow area, the first working fluid inlet (1-3-1) is connected to the output pipeline of the active thermal control component (2), the first working fluid outlet (1-3-2) is connected to the second working fluid inlet (1-4-1) through a pipeline, and the second working fluid outlet (1-4-2) is connected to the input pipeline of the active thermal control component (2). The antenna base plate (1-5) has through holes for each pipeline to pass through.

3. The thermal control device for a spaceborne active phased array antenna according to claim 1, characterized in that, The antenna assembly (1) is mounted on the satellite platform (3) via the antenna base plate (1-5), and the active thermal control assembly (2) is disposed within the satellite platform (3).

4. The thermal control device for a spaceborne active phased array antenna according to claim 1, characterized in that, The thermal control structure (1-3) has multiple parallel fluid channels connected between the first working fluid inlet (1-3-1) and the first working fluid outlet (1-3-2).

5. The thermal control device for a spaceborne active phased array antenna according to claim 1, characterized in that, The phase change thermal storage module (1-4) is also provided with a phase change material injection port (1-4-3).

6. A thermal control method for a spaceborne active phased array antenna, utilizing the thermal control device for a spaceborne active phased array antenna as described in any one of claims 1-5, characterized in that, The method includes: The temperature sensors (2-6) monitor the temperature of the antenna subarray (1-2); When the temperature of the antenna subarray (1-2) exceeds the threshold, the controller (2-7) controls the drive pump (2-2) to drive the thermal control working fluid in the storage tank (2-1) to circulate through the flow loop. During the circulation process, the thermal control working fluid absorbs heat from the antenna subarray (1-2), and when it passes through the phase change heat storage module (1-4), it transfers heat to the phase change material in the phase change heat storage module (1-4). Part of the heat is stored by the phase change material, and the other part of the heat is dissipated through the thermochromic smart coating (1-6). When the temperature of the antenna subarray (1-2) is less than the threshold, the controller (2-7) controls the drive pump (2-2) to drive the thermal control working fluid in the storage tank (2-1) to circulate through the flow loop. When the thermal control working fluid passes through the phase change heat storage module (1-4), at least part of the heat stored in the phase change material in the phase change heat storage module (1-4) is transferred to the thermal control working fluid, and the thermal control working fluid brings the heat to the antenna subarray (1-2) during circulation.

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