A satellite payload cooling system

Abstract

A satellite payload cooling system includes a gear pump, an automatic valve, a comparison circuit, and a control circuit. Heat dissipation coils are installed on the heat dissipation surfaces of required heat dissipation components within the satellite platform. A heat dissipation cartridge is installed on the gear pump's feed pipe. The gear pump's discharge pipe is connected to one end of each of the heat dissipation coils, and the other ends of the heat dissipation coils are connected in parallel to the heat dissipation cartridges. The automatic valve includes a valve body, a valve core, an electromagnetic coil, an armature, and a force-sensitive resistor, and the inlet and outlet pipes of the automatic valve are connected in series between the multiple heat dissipation coils. The comparison circuit includes a thermistor and an output subcircuit, with the thermistor installed on the heating surface of each component. The output subcircuit and the control circuit are installed within the satellite platform and electrically connected to the force-sensitive resistor and the thermistor. The present invention has a compact structure and lightweight weight, making it convenient for satellite platform installation. While effectively dissipating heat for corresponding components, it also prevents excessive heat dissipation from causing performance degradation of specific components.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite supporting equipment, in particular to a satellite payload heat dissipation system. Background Art

[0002] Because satellite platforms operate in the harsh space environment, heat-generating components are generally equipped with heat dissipation mechanisms. Existing satellite heat dissipation mechanisms are fixed installation models, with each component having a corresponding heat dissipation mechanism. Because the heat dissipation material of the heat dissipation mechanism is non-flowable, the heat dissipation effect is relatively poor, which can have a more or less adverse impact on the normal operation of the satellite. Although electric pumps can be used to pump out the flow of heat dissipation fluid to dissipate heat for related components, using a corresponding heat dissipation mechanism for each component will occupy valuable installation space on the satellite platform and increase the fire launch load accordingly. Furthermore, the above-mentioned electric pump heat dissipation method dissipates a fixed amount of heat dissipation pumped to each component, which means that the heat dissipation amount for the corresponding component is fixed. As a result, some special components need to maintain a certain operating temperature, and if the temperature is too low, it may not achieve good operating performance. Due to the above reasons, the heat dissipation mechanisms used in existing satellite platforms still have certain shortcomings. Summary of the Invention

[0003] In order to overcome the drawbacks of the heat dissipation mechanism used in existing satellite platforms due to structural limitations as described in the background, the present invention provides a satellite payload heat dissipation system that, under the joint action of relevant mechanisms and circuits, can provide circulating heat dissipation agent for various heat-generating components on the satellite platform through only a set of electric gear pumps, thereby achieving better heat dissipation effects and accurately controlling the amount of heat dissipation entering each component. On the premise of achieving good heat dissipation effects, it will not cause the temperature of the corresponding components to be too low, thereby providing favorable technical support for the normal operation of the satellite platform.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A satellite payload cooling system includes a gear pump, characterized in that it also has an automatic valve, a comparison circuit and a control circuit; the gear pump is installed in a satellite platform, and the cooling surfaces of the required cooling components in the satellite platform are all installed with cooling coils, the gear pump feed pipe is installed with a cooling agent box, the cooling agent box is filled with cooling agent, the gear pump discharge pipe is connected with multiple branch pipes in parallel, one end of the multiple branch pipes is respectively connected with one end of multiple cooling coils, and the other end of the multiple cooling coils is connected with the cooling agent box return pipe in parallel; there are multiple sets of automatic valves, each set of automatic valves includes a valve body, a valve core, an electromagnetic coil, an armature, and a force-sensitive resistor, an inlet pipe and an outlet pipe are respectively provided at both ends of the valve body, the valve core is located in the lower part of the valve body, the lower end of the armature is installed on the upper part of the valve core, the electromagnetic coil is installed in the valve body and at the upper end of the armature, the skeleton of the electromagnetic coil has an axial hole in the middle, and the armature The armature rod installed together at the upper end of the iron is led upward through the shaft hole, the upper end of the armature rod is installed with a buffer spring, and the force-sensitive resistor is insulated and installed at the upper end of the valve body; the inlet pipe and outlet pipe of the multiple sets of automatic valves are respectively connected in series between multiple branch pipes and one end of multiple heat dissipation coils; the comparison circuit and the control circuit each have the same multiple channels, the comparison circuit includes a thermistor and an output sub-circuit, and the thermistor of each comparison circuit is installed on the heating surface of each required heat dissipation component; the output sub-circuit and the control circuit of the multi-channel comparison circuit are installed in the satellite platform, and the two ends of the force-sensitive resistor of each set of automatic valves are electrically connected in series between the two signal input ends of each comparison circuit, the signal output end of each comparison circuit is electrically connected to the signal input end of each control circuit, and the power output end of each control circuit is electrically connected to the power input end of each set of automatic valves.

[0006] Furthermore, the upper end of the spring of each set of automatic valves and the lower end of the strain gauge generated by the force-sensitive resistor are in contact.

[0007] Furthermore, the output subcircuit of the comparison circuit includes an electrically connected adjustable resistor, an operational amplifier integrated circuit and a diode, and is connected to the thermistor. The positive power supply input terminal of the operational amplifier integrated circuit is connected to one end of the first adjustable resistor and one end of the second adjustable resistor. The output terminal of the operational amplifier integrated circuit is connected to the negative electrode of the diode. The other end of the first adjustable resistor is connected to one end of the thermistor, and the other end of the thermistor is connected to the reverse input terminal of the operational amplifier integrated circuit.

[0008] Furthermore, the control circuit includes an electrically connected resistor, a relay, and a PNP transistor, the positive power input end of the relay is connected to the collector of the PNP transistor, the control power input end of the relay is connected to the emitter of the PNP transistor, and one end of the resistor is connected to the base of the PNP transistor.

[0009] The beneficial effects of the present invention are as follows: a set of electric gear pumps of the present invention can dissipate heat for all components that require heat dissipation. It has a compact structure, is relatively lightweight, and does not occupy a relatively large amount of installation space, making it convenient for satellite platforms to carry it. In the present invention, the pressure heat dissipating agent (such as heat dissipating silicone grease, etc.) output by the electric gear pump during operation circulates into the heat dissipating coils of the corresponding heat dissipating components and takes away the heat generated by the components. Under the action of the thermistor and the force-sensitive resistor, the higher the temperature of the heat dissipating component, the greater the degree of opening of the valve core of the automatic valve, and the more heat dissipating agent enters the heat dissipating coil, and vice versa. This effectively dissipates heat for the corresponding components while preventing excessive heat dissipation from causing a decrease in the working performance of special components. In summary, the present invention has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0011] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0012] Figure 2 It is a structural schematic diagram of the automatic valve of the present invention.

[0013] Figure 3 It is a circuit diagram of the present invention. DETAILED DESCRIPTION

[0014] Figure 1 、 2As shown in , 3, a satellite payload cooling system includes a micro gear pump 1 (working voltage 12V, power 15W), an automatic valve, a comparison circuit and a control circuit 2; the gear pump is installed in the satellite platform, and the required heat dissipation components in the satellite platform are closely mounted with small serpentine heat dissipation coils 3, the feed pipe of the gear pump 1 is installed with a heat dissipation agent box 4, the heat dissipation agent box 4 is filled with heat dissipation agent, the discharge pipe of the gear pump 1 is connected in parallel with multiple branch pipes 5, one end of the multiple branch pipes 5 is respectively connected to one end of the multiple heat dissipation coils 3, and the other end of the multiple heat dissipation coils 3 is refluxed to the upper end of the heat dissipation agent box 4. One end of the tube 6 is connected in parallel; there are multiple sets of automatic valves, each set of automatic valves includes a cylindrical valve body 7 with sealed upper and lower ends, a circular valve core 8, a circular electromagnetic coil DC (working voltage 12V, power 0.3W), a circular armature 9, and a force-sensitive resistor RW. An inlet pipe 71 and an outlet pipe 72 are each installed horizontally at the lower middle part of the left and right ends of the valve body 7. The valve core 8 (ceramic material) is located in the lower part of the valve body 7. The lower end of the armature 9 is glued to the upper middle part of the valve core 8 (the outer end is sealed with the valve body 7 and can move up and down). The electromagnetic coil DC is installed in the middle of the valve body 7 and is located at the upper end of the armature 9 (a certain distance apart). ), there is an axial hole in the middle of the skeleton of the electromagnetic coil DC, and the armature rod 91 welded to the upper end of the middle of the armature (made of steel, with an outer diameter smaller than the outer diameter of the valve core) is led upward through the axial hole (the outer diameter of the armature rod 91 is smaller than the inner diameter of the axial hole), and a spring 92 is welded to the upper end of the armature rod 91. The force-sensitive resistor RW is insulated and installed in the middle of the upper end of the valve body 7, and its strain gauge is located at the lower end. When the valve core 8 is at the bottom dead center of the valve body, the inlet pipe 71 and the outlet pipe 72 are closed by about four-fifths; the inlet pipes 71 and outlet pipes 72 of the multiple sets of automatic valves are respectively connected in series between the multiple branch pipes 5 and one end of the multiple heat dissipation coils 3. ; The comparison circuit and control circuit 2 each have the same multiple channels, and the number of multiple heat dissipation components required for the satellite platform is consistent with the number of channels of the comparison circuit and control circuit 2. Each comparison circuit and control circuit 2 is equipped with a required heat dissipation component and a set of automatic valves; the comparison circuit includes a thermistor RT and an output sub-circuit 10, and the thermistor RT of each comparison circuit is installed on the heating surface of each required heat dissipation component, and the heat transfer surface of the thermistor RT is in close contact with the heating surface of the required heat dissipation component; the output sub-circuit 10 of the multi-channel comparison circuit and the control circuit 2 are installed in the electrical control box of the satellite platform.

[0015] Figure 1 、 2As shown in Figures 3 and 4, the upper end of spring 92 of each automatic valve is in contact with the lower end of the strain gauge of force-sensitive resistor RW. The output subcircuit of the comparison circuit includes adjustable resistors RP and RP1, op amp integrated circuit A1, and diode VD, all connected via circuit board wiring. These are also connected to thermistor RT via wires. The positive power input pin 1 of op amp integrated circuit A1 is connected to one end of the first adjustable resistor RP and one end of the second adjustable resistor RP1. The output pin 1 of op amp integrated circuit A1 is connected to the cathode of diode VD. The other end of the first adjustable resistor RP is connected to one end of thermistor RT, which is then connected to the inverting input pin 2 of op amp integrated circuit A1. The control circuit includes resistor R1, relay K1, and PNP transistor Q1, all connected via circuit board wiring. The positive power input of relay K1 is connected to the collector of PNP transistor Q1, the control power input of relay K1 is connected to the emitter of PNP transistor Q1, and one end of resistor R1 is connected to the base of PNP transistor Q1.

[0016] Figure 1 、 2 As shown in Figures 3 and 4, the power input terminals of the multi-channel comparison circuit are connected to the positive power input terminal 4 and the negative power input terminal 8 of the op amp integrated circuit A1. The control circuit power input terminal, the control power input terminal, and the negative power input terminal of relay K1 are connected to the two poles of the power supply of battery G on the satellite platform via wires. The two ends of the force-sensitive resistor RT of each automatic valve are connected in series via wires between the other end of the adjustable resistor RP1 at the two signal input terminals of each comparison circuit and the non-inverting input terminal 3 of op amp integrated circuit A1. The positive electrode of the diode VD at the signal output terminal of each comparison circuit is connected to the other end of the resistor R1 at the signal input terminal of each control circuit via wires. The normally open contact terminal and the negative power input terminal of relay K1 at the power output terminal of each control circuit are connected to the DC power input terminals of the electromagnetic coil of each automatic valve via wires.

[0017] Figure 1 、 2As shown in Figures 3 and 4, after the power output from the battery G of the present invention enters the multi-channel comparison circuit and the multi-channel control circuit, the multi-channel comparison circuit and the multi-channel control circuit are in an energized operating state. When the electric gear pump 1 is operating (which can operate continuously or be controlled by the satellite platform control board to operate at specific times), it pumps the heat sink (such as thermal grease) from the heat sink box 4 through multiple branch pipes 5 and outputs it to the multiple heat sinks 3 (entering at one end of the heat sink). The heat sink then flows out of the other end of the heat sink 3 and back into the heat sink box 4. As the heat sink flows into and out of the heat sink 3, it removes heat generated by the required heat dissipation components. In the present invention, the thermistor RT detects the temperature of the relevant heat dissipation components in real time. The higher the temperature, the lower the resistance value of the thermistor RT, and vice versa. The 12V positive power supply output by the battery G enters the reverse input terminal 2 of the operational amplifier integrated circuit A1 through the adjustable resistor RP and the thermistor RT for voltage reduction and current limiting; the 12V positive power supply enters the non-inverting input terminal 3 of the operational amplifier integrated circuit A1 through the force-sensitive resistor RW (the greater the pressure of the spring 92 applied to the strain gauge of the force-sensitive resistor RW, the smaller the resistance, and vice versa) and the adjustable resistor RP1 for voltage reduction and current limiting. In practice, when the temperature of the component to be cooled is higher than a set temperature (e.g., 55°C), the resistance of thermistor RT is relatively low. Consequently, the positive electrode of the 12V power supply, after being stepped down and limited by the adjustable resistor RP and thermistor RT, enters the inverting input terminal 2 of the operational amplifier integrated circuit A1 at a voltage (e.g., 7V) higher than the non-inverting input terminal 3 (e.g., 6V). Due to the action of its internal circuitry, pin 1 of the operational amplifier integrated circuit A1 outputs a low level, which is then unidirectionally conducted by diode VD. Resistor R1 steps down and limits the current, and the voltage enters the base of the PNP transistor Q1. The PNP transistor Q1 conducts, and its collector outputs a high level, which enters the negative power input terminal of relay K1. Relay K1 is then energized, closing its control power input terminal and normally open contact. The electromagnetic coil DC is energized to generate a magnetic force, which in turn drives the armature 9 upward, driving the valve core 8. This magnetic force reduces the degree to which the valve core 8 seals the inlet pipe 71 and outlet pipe 72. This increases the amount of heat within the heat dissipation coil 4 at the corresponding component controlled by this electric valve, thereby enhancing the heat dissipation effect on that component. When the armature moves upward, the strain gauge force of the spring 92 (the tighter the compression, the greater the force) acting on the force-sensitive resistor RW increases. When the force acting on the strain gauge of the force-sensitive resistor RW is appropriate, the resistance value of the force-sensitive resistor RW becomes relatively small. The positive electrode of the 12V power supply enters the non-inverting input terminal 3 of the operational amplifier integrated circuit A1 after being stepped down by the adjustable resistor RP1 and the force-sensitive resistor RW, and the voltage is higher than the voltage of the reverse input terminal 2. In this way, pin 1 of the operational amplifier integrated circuit A1 stops outputting a low level, and then the relay K1 and the electromagnetic coil DC are both de-energized. The valve core moves downward to close the part between the inlet pipe 71 and the outlet pipe 72, and the amount of heat dissipation entering the corresponding heat dissipation coil will be relatively reduced.In practice, if the temperature of the corresponding component is high, the operating time of the electromagnetic coil DC is extended. This will extend the time that the voltage at the low-voltage pin 2 of the inverting input terminal of the op amp integrated circuit A1 is higher than the voltage at the non-inverting input terminal, pin 3. This will extend the time that the valve core of the corresponding electric valve is open, increase the amount of heat dissipation flowing into and out of the corresponding heat dissipation coil 3, and increase the flow frequency of the heat dissipation agent, thus achieving a better heat dissipation effect on the corresponding component. When the temperature of the corresponding component again exceeds the set value, the voltage entering pin 2 of the op amp integrated circuit will become higher than the voltage at pin 3. Pin 1 of the op amp integrated circuit will output a low level and enter the collector of the PNP transistor Q1. Furthermore, relay K1 will be energized and attracted, and the electromagnetic coil DC will be energized to generate permanent magnetic force, and the amount of heat dissipation flowing from the valve core into the corresponding heat dissipation coil will decrease again. Through the combined action of the above-mentioned mechanisms and circuits, a set of electric gear pumps of the present invention can dissipate heat for all components that require heat dissipation. It has a compact structure, is relatively lightweight, and does not occupy a relatively large amount of installation space, which is beneficial for being carried on a satellite platform. When the micro electric gear pump is working, the pressurized heat dissipant (such as heat dissipation silicone grease, etc.) output by the micro electric gear pump circulates into the heat dissipation coils of the corresponding heat dissipation components and takes away the heat generated by the components. Under the action of the thermistor and the force-sensitive resistor, the higher the temperature of the heat dissipation component, the greater the degree of opening of the valve core of the automatic valve, and the more heat dissipation enters the heat dissipation coil, and vice versa. This effectively dissipates heat for the corresponding components while preventing the working performance of special components from being reduced due to excessive heat dissipation. In the circuit, the PNP transistor Q1 is model 9012; the resistance of resistor R1 is 1K; the relay K1 is a DC12V relay; the adjustable resistors RP and RP1 are models 4.7M (in this embodiment, they are adjusted to 1.7M and 1.3M, respectively); the thermistor RT is a negative temperature coefficient thermistor model NTC-103D; the diode VD is model 1N4007; the force-sensitive resistor RW is model IMS-C04N; and the operational amplifier integrated circuit A1 is model NE5532N. The technicians of the present invention can set the heat dissipation threshold of the corresponding component by adjusting the resistance value of the adjustable resistor RP. When the resistance value of the adjustable resistor RP is adjusted to a relatively large value, the component temperature is relatively high, and the resistance value of the thermistor RT is relatively small, the voltage at pin 2 entering the operational amplifier integrated circuit A1 will be higher than the voltage at pin 3. Then, the electromagnetic coil DC will be energized at a relatively high component temperature, and the valve core will be opened to a greater extent. When the resistance value of the adjustable resistor RP is adjusted to a relatively small value, the component temperature is relatively low, and the resistance value of the thermistor RT is relatively large, the voltage at pin 2 entering the operational amplifier integrated circuit A1 will be higher than the voltage at pin 3. Then, the electromagnetic coil DC will be energized at a relatively low component temperature, and the valve core will be opened to a greater extent.

[0018] The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims rather than the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are intended to be included therein.

[0019] In addition, it should be understood that although this specification is described in terms of implementation methods, the implementation methods do not only include an independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A satellite payload cooling system, comprising a gear pump, characterized in that The invention also has an automatic valve, a comparison circuit and a control circuit; the gear pump is installed in the satellite platform, and the heat dissipation surfaces of the required heat dissipation components in the satellite platform are installed with heat dissipation coils, the feed pipe of the gear pump is installed with a heat dissipation agent box, and the heat dissipation agent box is filled with heat dissipation agent, and the discharge pipe of the gear pump is connected with multiple branch pipes in parallel, and one end of the multiple branch pipes is respectively connected with one end of the multiple heat dissipation coils, and the other end of the multiple heat dissipation coils is connected with the heat dissipation agent box return pipe in parallel; there are multiple sets of automatic valves, and each set of automatic valves includes a valve body, a valve core, an electromagnetic coil, an armature, and a force-sensitive resistor. There is an inlet pipe and an outlet pipe at each end of the valve body, the valve core is located in the lower part of the valve body, the lower end of the armature is installed on the upper part of the valve core, the electromagnetic coil is installed in the valve body and at the upper end of the armature, and there is an axial hole in the middle of the skeleton of the electromagnetic coil, and the armature installed together with the upper end of the armature The iron rod is led upward through the shaft hole, a buffer spring is installed on the upper end of the armature rod, and a force-sensitive resistor is insulated and installed in the upper end of the valve body; the inlet pipes and outlet pipes of the multiple sets of automatic valves are respectively connected in series between multiple branch pipes and one end of multiple heat dissipation coils; the comparison circuit and the control circuit each have the same multiple channels, the comparison circuit includes a thermistor and an output sub-circuit, and the thermistor of each comparison circuit is installed on the heating surface of each required heat dissipation component; the output sub-circuit and the control circuit of the multi-channel comparison circuit are installed in the satellite platform, and the two ends of the force-sensitive resistor of each set of automatic valves are electrically connected in series between the two signal input ends of each comparison circuit, the signal output end of each comparison circuit is electrically connected to the signal input end of each control circuit, and the power output end of each control circuit is electrically connected to the power input end of each set of automatic valves.

2. A satellite payload cooling system according to claim 1, characterized in that: The upper end of the spring of each set of automatic valves and the lower end of the strain gauge generated by the force-sensitive resistor are in contact.

3. A satellite payload cooling system according to claim 1, characterized in that: The output subcircuit of the comparison circuit includes an electrically connected adjustable resistor, an operational amplifier integrated circuit and a diode, and is also connected to the thermistor. The positive power supply input terminal of the operational amplifier integrated circuit is connected to one end of the first adjustable resistor and one end of the second adjustable resistor. The output terminal of the operational amplifier integrated circuit is connected to the negative electrode of the diode. The other end of the first adjustable resistor is connected to one end of the thermistor, and the other end of the thermistor is connected to the reverse input terminal of the operational amplifier integrated circuit.

4. The satellite payload cooling system according to claim 1, characterized in that: The control circuit includes an electrically connected resistor, a relay, and a PNP transistor. The positive power input end of the relay is connected to the collector of the PNP transistor, the control power input end of the relay is connected to the emitter of the PNP transistor, and one end of the resistor is connected to the base of the PNP transistor.

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