Space temperature measurement and control circuit

Abstract

The invention discloses a space temperature measurement and control circuit which comprises a DC-DC module, a partial pressure measurement circuit, a voltage amplification circuit, an AD sampling circuit, a signal processor, a temperature control circuit and a telemetering circuit. The DC-DC module converts a primary power supply into a secondary power supply, the partial pressure measuring circuit realizes acquisition of voltage change caused by temperature change, the voltage amplifying circuit realizes voltage magnitude amplification, the AD sampling circuit realizes acquisition of voltage signals, the signal processor realizes processing and logical judgment of the voltage signals, and the temperature control circuit realizes on-off control of heating to a device. And the remote control circuit realizes switching of the main and backup circuits. And the temperature measuring circuit adopts a hot backup circuit, so that the reliability is improved, and meanwhile, the precision can be improved by adopting a two-path mean value. The temperature control circuit adopts a cold backup circuit, and the main and standby circuits are switched through a remote control instruction, so that the long-time working reliability of the temperature control circuit is improved, and a high-reliability system which is operated continuously for a long time has a stable and reliable temperature control function.

Description

Technical Field

[0001] The present application relates to the technical field of temperature measurement and temperature control, and in particular to a space temperature measurement and temperature control circuit. Background Art

[0002] The filter wheel device is a device for realizing multi-spectral imaging of geostationary orbit space optical remote sensors. The device filters the light entering the system by rotating the filters evenly distributed on the filter wheel turntable, so that each spectral band is imaged separately. In order to ensure the high and low temperature difference of infrared testing, it is necessary to add a calibration piece to the filter wheel turntable, spray black paint or blackening treatment on the surface of the calibration piece, and paste electric heating devices and thermistors on the back. When in use, the temperature of the calibration piece is dynamically controlled to ensure that the temperature difference between the calibration piece and the environment is within the required range, so as to facilitate the imager to collect high temperature information. Therefore, it is of great significance to design a space temperature measurement and control circuit that can simultaneously measure the calibration piece and the ambient temperature, and control the heating of the calibration piece according to the temperature difference between the calibration piece and the environment.

[0003] Therefore, there is an urgent need for a space temperature measurement and control circuit. Summary of the invention

[0004] The purpose of the present invention is to provide a space temperature measurement and control circuit to realize the heating control of the calibration piece during the infrared test process. In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] In a first aspect, the present invention provides a space temperature measurement and temperature control circuit, the space temperature measurement and temperature control circuit comprising: a DC-DC module, a voltage division measurement circuit, a voltage amplification circuit, an AD sampling circuit, a signal processor, and a temperature control circuit;

[0006] The first DC-DC module is electrically connected to the voltage division measurement circuit, the voltage division measurement circuit is electrically connected to the voltage amplifier circuit, the voltage amplifier circuit is electrically connected to the AD sampling circuit, the AD sampling circuit is electrically connected to the signal processor, and the second end of the signal processor is electrically connected to the temperature control circuit; the voltage division measurement circuit is provided with multiple thermistors and at least one fixed resistor;

[0007] The second DC-DC module is electrically connected to the other end of the temperature control circuit, the first DC-DC module is connected to a primary power supply, and the second DC-DC module is connected to a primary power supply;

[0008] The primary power supply enters the DC-DC module for processing to form a secondary power supply. The secondary power supply enters the voltage division measurement circuit and is divided into multiple paths. The secondary power supply forms voltage signals of corresponding numbers through multiple thermistors. The secondary power supply forms a reference voltage signal through at least one fixed resistor. The absolute temperature is determined by the multiple voltage signals and the reference voltage signal to eliminate errors caused by fluctuations in the secondary power supply.

[0009] In another embodiment of the present invention, the space temperature measurement and control circuit further includes a backup circuit, and the backup circuit includes: a first backup DC-DC module, a second voltage division measurement circuit, a second voltage amplification circuit, and a second backup DC-DC module;

[0010] The first backup DC-DC module is electrically connected to the voltage division measurement circuit, the voltage division measurement circuit is electrically connected to the second voltage amplification circuit, and the second voltage amplification circuit is electrically connected to the AD sampling circuit;

[0011] The third terminal of the signal processor is electrically connected to the second temperature control circuit, and the second temperature control circuit is electrically connected to the second backup DC-DC module.

[0012] In another embodiment of the present invention, the space temperature measurement and control circuit further includes: a control instruction module and a remote control circuit;

[0013] The fourth terminal of the signal processor is electrically connected to the control instruction, the control instruction is electrically connected to the remote control circuit, and the remote control circuit is used to control the second DC-DC module and / or the second backup DC-DC module.

[0014] In another embodiment of the present invention, the voltage amplification circuit includes: a lead-in amplification circuit and a differential amplification circuit;

[0015] The first output terminal of the voltage division measurement circuit is electrically connected to the first differential amplifier circuit, and the second output terminal is electrically connected to the first differential amplifier circuit;

[0016] The first output terminal of the second voltage-dividing measurement circuit is electrically connected to the second differential amplifier circuit, and the second output terminal is electrically connected to the second differential amplifier circuit.

[0017] In another embodiment of the present invention, the voltage division measurement circuit comprises: a plurality of thermistors and at least one fixed resistor;

[0018] Each thermistor is connected in series with a preset fixed resistor, and multiple thermistors are connected in parallel;

[0019] At least one fixed resistor is connected in series with a preset fixed resistor, and at least one fixed resistor is connected in parallel with the multi-channel thermistor.

[0020] In another embodiment of the present invention, the voltage amplification circuit includes: a common-direction amplification circuit and a differential amplification circuit;

[0021] The input end leading to the amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit; the input end of the differential amplifier circuit is electrically connected to the second output end of the voltage divider measurement circuit.

[0022] In another embodiment of the present invention, the voltage amplifier circuit comprises: a first same-direction amplifier circuit, a second same-direction amplifier circuit, a third same-direction amplifier circuit, and a differential amplifier circuit;

[0023] The input end of the first unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, the input end of the second unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, the input end of the third unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, and the differential amplifier circuit is electrically connected to the second output end of the voltage divider measurement circuit.

[0024] In another embodiment of the present invention, the temperature control circuit includes: a first resistance circuit, a Schottky diode, a heating circuit, a field effect transistor, a switching transistor, a voltage regulator diode, and a second resistance circuit;

[0025] The input end of the first resistance circuit, the input end of the Schottky diode, and the input end of the heating circuit are respectively connected to the input end of the temperature control circuit; the output end of the first resistance circuit is respectively connected to the switching transistor, the voltage-stabilizing diode, the resistance circuit, and the field-effect transistor; the output end of the Schottky diode and the output end of the heating circuit are respectively connected to the second input end of the field-effect transistor; the output ends of the switching transistor, the voltage-stabilizing diode, the second resistance circuit, and the field-effect transistor are respectively connected to the output end of the temperature control circuit.

[0026] In the second aspect, the present invention further provides a space temperature measurement and temperature control device, which is arranged in the filter wheel device and is used to heat the calibration plate of the filter wheel device. The space temperature measurement and temperature control circuit described in any embodiment of the first aspect is arranged in the space temperature measurement and temperature control device.

[0027] In a third aspect, the present invention further provides a filter wheel device, wherein the filter wheel device is provided with the spatial temperature control and temperature measurement circuit described in any embodiment of the first aspect.

[0028] The beneficial effects of the present invention are as follows:

[0029] The present invention discloses a space temperature measurement and control circuit, comprising: a DC-DC module, a voltage division measurement circuit, a voltage amplifier circuit, an AD sampling circuit, a signal processor, a temperature control circuit and a telemetry circuit. The DC-DC module realizes the conversion of a primary power supply to a secondary power supply, the voltage division measurement circuit realizes the collection of voltage changes caused by temperature changes, the voltage amplifier circuit realizes the amplification of the voltage magnitude, the AD sampling circuit realizes the collection of voltage signals, the signal processor realizes the processing and logical judgment of voltage signals, the temperature control circuit realizes the switching control of the heating device, and the remote control circuit realizes the switching of the main and backup circuits. The temperature measurement circuit adopts a hot backup circuit, which not only improves the reliability, but also can adopt the average of the two paths to improve the accuracy. The temperature control circuit adopts a cold backup circuit, and the long-term working reliability of the temperature control circuit is improved by switching the main and backup circuits through remote control commands, so that the system with long-term uninterrupted operation and high reliability has a stable and reliable temperature control function. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the principle of a space temperature measurement and control circuit provided by an embodiment of the present invention;

[0031] Figure 2 A schematic diagram of the principle of a voltage divider measurement circuit in a space temperature measurement and control circuit provided by an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of the principle of a voltage amplification circuit in a space temperature measurement and control circuit provided by an embodiment of the present invention;

[0033] Figure 4 A schematic diagram of the principle of a temperature control circuit in a space temperature measurement and control circuit provided by an embodiment of the present invention;

[0034] In the figure: 1. DC-DC power supply chip; 2. voltage division measurement circuit; 3. common direction amplifier circuit; 4. differential amplifier circuit; 5. AD sampling circuit; 6. signal processor; 7. temperature control circuit; 8. DC-DC power supply chip; 9. remote control circuit; 10. fixed resistor; 11. thermistor; 12. fixed resistor; 13. thermistor; 14. fixed resistor; 15. fixed resistor; 16. common direction amplifier circuit 1; 17. common direction amplifier circuit 2; 18. common direction amplifier circuit 3; 19. differential amplifier circuit; 20. switching transistor; 21. voltage regulator diode; 22. resistor circuit 2; 23. field effect transistor; 24. resistor circuit 1; 25. Schottky diode; 26. heating circuit. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of this specification clearer, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and their corresponding drawings. Obviously, the described embodiments are only part of the embodiments of this specification, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this document.

[0036] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0037] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0038] The terms used herein are only used to describe specific embodiments and are not intended to limit the present invention. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, the presence of the features, wholes, steps, operations, elements and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof is not excluded.

[0039] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be understood to have a meaning consistent with their meaning in the context of the relevant art and the present invention, and will not be understood to have an idealized or overly formal meaning unless explicitly defined as such herein.

[0040] The following combination Figure 1-4 , describes in detail the technical solutions provided by each embodiment of this specification. Specific embodiment 1:

[0042] A space temperature measurement and control circuit, characterized in that it includes a voltage division measurement circuit, a voltage amplifier circuit, an AD sampling chip, a signal processor, and a temperature control circuit arranged in sequence; and also includes a DC-DC power supply chip respectively arranged at the input end of the voltage division measurement circuit and the input end of the temperature control circuit; wherein:

[0043] A primary power supply signal is input to the power input end of the DC-DC power supply chip at the input end of the voltage division measurement circuit and the power input end of the DC-DC power supply chip at the input end of the temperature control circuit;

[0044] The voltage output end of the DC-DC power supply chip at the input end of the voltage divider measurement circuit is connected to the power input end of the voltage divider measurement circuit; the voltage output end of the DC-DC power supply chip at the input end of the temperature control circuit is connected to the power input end of the temperature control circuit; the voltage divider output end of the voltage divider measurement circuit is connected to the input end of the voltage amplifier circuit; the amplification output end of the voltage amplifier circuit is connected to the sampling input end of the AD sampling chip; the signal transmission end of the AD sampling chip is connected to the signal transmission end of the signal processor; the signal transmission end of the signal processor is connected to the switch signal input end of the temperature control circuit.

[0045] The DC-DC power supply chip, voltage division measurement circuit and voltage amplifier circuit at the input end of the voltage division measurement circuit include a DC-DC power supply chip, voltage division measurement circuit and voltage amplifier circuit at the input end of the voltage division measurement circuit of the main circuit and a DC-DC power supply chip, voltage division measurement circuit and voltage amplifier circuit at the input end of the voltage division measurement circuit of the standby circuit, wherein:

[0046] The voltage output end of the DC-DC power supply chip at the input end of the main circuit voltage-dividing measurement circuit is connected to the power input end of the main circuit voltage-dividing measurement circuit; the voltage-dividing output end of the main circuit voltage-dividing measurement circuit is connected to the input end of the main circuit voltage amplifying circuit; the amplified output end of the main circuit voltage amplifying circuit is connected to the sampling input end of the AD sampling chip; the voltage output end of the DC-DC power supply chip at the input end of the standby circuit voltage-dividing measurement circuit is connected to the power input end of the standby circuit voltage-dividing measurement circuit; the voltage-dividing output end of the standby circuit voltage-dividing measurement circuit is connected to the input end of the standby circuit voltage amplifying circuit; the amplified output end of the standby circuit voltage amplifying circuit is connected to the sampling input end of the AD sampling chip.

[0047] The DC-DC power chip at the input end of the temperature control circuit and the temperature control circuit include a DC-DC power chip at the input end of the temperature control circuit of the main circuit, a temperature control circuit and a DC-DC power chip at the input end of the temperature control circuit of the standby circuit, a temperature control circuit, wherein:

[0048] The voltage output end of the DC-DC power supply chip at the input end of the main circuit temperature control circuit is connected to the power input end of the main circuit temperature control circuit; the switch signal input end of the main circuit temperature control circuit is connected to the signal transmission end of the signal processor; the voltage output end of the DC-DC power supply chip at the input end of the standby circuit temperature control circuit is connected to the power input end of the main circuit temperature control circuit; the switch signal input end of the standby circuit temperature control circuit is connected to the signal transmission end of the signal processor.

[0049] Also included is a remote control circuit, wherein:

[0050] The input end of the remote control circuit is connected to the signal transmission end of the signal processor to receive control instructions; the output end of the remote control circuit is respectively connected to the inhibit end pins of the DC-DC power supply chip at the input end of the main circuit temperature control circuit and the DC-DC power supply chip at the input end of the standby circuit temperature control circuit; when the inhibit end pin of the main circuit DC-DC power supply chip is suspended and the inhibit end pin of the standby circuit DC-DC power supply chip is grounded, the main circuit power supply works; when the inhibit end pin of the standby circuit DC-DC power supply chip is suspended and the inhibit end pin of the main circuit DC-DC power supply chip is grounded, the standby circuit power supply works.

[0051] The remote control circuit comprises a relay and a Schottky diode, wherein the Schottky diode is connected in reverse parallel at two ends of the relay.

[0052] The main circuit voltage amplifier circuit and the standby circuit voltage amplifier circuit both include a common-mode amplifier circuit and a differential amplifier circuit.

[0053] The main circuit voltage division measurement circuit and the standby circuit voltage division measurement circuit both include three branches arranged in parallel, one of which is connected in series with two fixed resistors, and the other two branches are connected in series with a fixed resistor and a thermistor, wherein:

[0054] The voltage-dividing output ends of the two fixed resistance branches are connected to the input end of the same-direction amplifier circuit; the voltage-dividing output ends of the two branches connected in series with a fixed resistor and a thermistor are respectively connected to the two input ends of the same-direction amplifier circuit and to the two input ends of the same differential amplifier circuit.

[0055] The fixed resistor at the power supply end of the two fixed resistor branches has the same resistance value as the fixed resistors on the other two branches.

[0056] The main circuit temperature control circuit and the backup circuit temperature control circuit both include two branches arranged in parallel, one of which includes two groups of resistance circuits arranged in series, and also includes a switching circuit arranged in parallel with the grounding terminal resistance circuit and a voltage stabilizing circuit arranged in parallel, and the other branch includes a freewheeling circuit and a switching circuit arranged in series, and also includes a heating circuit connected in parallel with the freewheeling circuit.

[0057] The resistance circuit is a main-backup setting structure, the switching circuit includes a switching diode circuit, the voltage stabilizing circuit includes a voltage stabilizing diode circuit, the freewheeling circuit includes a freewheeling diode circuit, the switching circuit includes a field effect transistor circuit, and the heating circuit includes an inductor circuit and a heating device.

[0058] The space temperature measurement and temperature control circuit provided by the present invention can sense the temperature of the target object and the required comparative ambient temperature and heat the target object to the required temperature. The temperature measurement circuit can measure not only the absolute temperature but also the relative temperature. At the same time, a hot backup design is adopted, which not only improves the reliability but also improves the accuracy by adopting the two-way average. The temperature control circuit can not only operate stably under the condition of frequent opening and closing, but also prevent the components from being damaged in the case of sudden voltage changes or fluctuations. At the same time, a cold backup circuit is adopted, and the main backup circuit is switched by remote control commands to improve the long-term working reliability of the temperature control circuit, so that the system with long-term uninterrupted operation and high reliability has a stable and reliable temperature control function. Specific embodiment 2:

[0060] In order to achieve temperature measurement and temperature control of the calibration piece during infrared testing, the present invention aims to provide a spatial temperature measurement and temperature control circuit. In order to enable those skilled in the art to better understand the technical solution, a spatial temperature measurement and temperature control circuit provided by the present invention is described in detail below in conjunction with the accompanying drawings.

[0061] The present invention provides a space temperature measurement and control circuit, comprising a voltage division measurement circuit 2, voltage amplification circuits 3 and 4, an AD sampling chip 5, a signal processor 6, and a temperature control circuit 7 arranged in sequence; and also comprising DC-DC power supply chips 1 and 9 respectively arranged at the input end of the voltage division measurement circuit and the input end of the temperature control circuit; wherein:

[0062] like Figure 1 As shown, a primary power supply signal is input to the power input end of the DC-DC power chip 1 at the input end of the voltage division measurement circuit and the power input end of the DC-DC power chip 9 at the input end of the temperature control circuit;

[0063] The voltage output terminal of the DC-DC power supply chip 1 at the input terminal of the voltage division measurement circuit is connected to the power input terminal of the voltage division measurement circuit 2;

[0064] The voltage output end of the DC-DC power chip 9 at the input end of the temperature control circuit is connected to the power input end of the temperature control circuit 7;

[0065] The voltage division output terminal of the voltage division measurement circuit 2 is connected to the input terminals of the voltage amplifier circuits 3 and 4;

[0066] The amplification output terminals of the voltage amplification circuits 3 and 4 are connected to the sampling input terminals of the AD sampling chip 5;

[0067] The signal transmission end of the AD sampling chip 5 is connected to the signal transmission end of the signal processor 6;

[0068] The signal transmission end of the signal processor 6 is connected to the switch signal input end of the temperature control circuit 7 .

[0069] The space temperature measurement and temperature control circuit provided by the present invention is provided with a temperature measurement and temperature control circuit.

[0070] In some embodiments, the DC-DC power supply chip, the voltage division measurement circuit and the voltage amplifier circuit at the input end of the voltage division measurement circuit include the DC-DC power supply chip, the voltage division measurement circuit and the voltage amplifier circuit at the input end of the voltage division measurement circuit of the main circuit and the DC-DC power supply chip, the voltage division measurement circuit and the voltage amplifier circuit at the input end of the voltage division measurement circuit of the standby circuit, wherein:

[0071] The voltage output end of the DC-DC power supply chip at the input end of the main circuit voltage division measurement circuit is connected to the power input end of the main circuit voltage division measurement circuit;

[0072] The voltage division output terminal of the main circuit voltage division measuring circuit is connected to the input terminal of the main circuit voltage amplifying circuit;

[0073] The amplification output end of the voltage amplification circuit of the main circuit is connected to the sampling input end of the AD sampling chip;

[0074] The voltage output end of the DC-DC power supply chip at the input end of the standby circuit voltage division measurement circuit is connected to the power input end of the standby circuit voltage division measurement circuit;

[0075] The voltage division output terminal of the standby circuit voltage division measuring circuit is connected to the input terminal of the standby circuit voltage amplifying circuit;

[0076] The amplification output end of the voltage amplification circuit of the standby circuit is connected to the sampling input end of the AD sampling chip.

[0077] By adopting the hot backup circuit, not only the safety and reliability of the temperature measurement function are improved, but also the temperature measurement accuracy is improved.

[0078] In some embodiments, the DC-DC power supply chip at the input end of the temperature control circuit and the temperature control circuit include a DC-DC power supply chip at the input end of the temperature control circuit of the main circuit, a temperature control circuit, and a DC-DC power supply chip at the input end of the temperature control circuit of the standby circuit, and a temperature control circuit, wherein:

[0079] The voltage output end of the DC-DC power supply chip at the input end of the main circuit temperature control circuit is connected to the power input end of the main circuit temperature control circuit;

[0080] The current input terminal of the main circuit temperature control circuit is connected to the signal transmission terminal of the signal processor;

[0081] The voltage output end of the DC-DC power supply chip at the input end of the standby circuit temperature control circuit is connected to the power input end of the main circuit temperature control circuit;

[0082] The current input end of the standby circuit temperature control circuit is connected to the signal transmission end of the signal processor.

[0083] In some embodiments, further comprising a remote control circuit, wherein:

[0084] The input end of the remote control circuit is connected to the signal transmission end of the signal processor to receive the control instruction;

[0085] The output end of the remote control circuit is respectively connected to the inhibit end pins of the DC-DC power chip at the input end of the main circuit temperature control circuit and the DC-DC power chip at the input end of the standby circuit temperature control circuit; when the inhibit end pin of the main circuit DC-DC power chip is suspended and the inhibit end pin of the standby circuit DC-DC power chip is grounded, the main circuit power supply works; when the inhibit end pin of the standby circuit DC-DC power chip is suspended and the inhibit end pin of the main circuit DC-DC power chip is grounded, the standby circuit power supply works.

[0086] Specifically, the remote control circuit includes a relay and a Schottky diode, and the Schottky diode is connected in reverse parallel at both ends of the relay.

[0087] In some embodiments, the main circuit voltage amplifier circuit and the standby circuit voltage amplifier circuit both include a common-mode amplifier circuit and a differential amplifier circuit.

[0088] In some embodiments, the main circuit voltage division measurement circuit and the standby circuit voltage division measurement circuit each include three branches arranged in parallel, one of which is connected in series with two fixed resistors, and the other two branches are each connected in series with a fixed resistor and a thermistor, wherein:

[0089] The voltage-dividing output ends of the two fixed resistance branches are connected to the input end of the same-direction amplifying circuit;

[0090] The voltage-dividing output ends of the two branches of a fixed resistor and a thermistor connected in series are respectively connected to the two input ends of the same-direction amplifier circuit and are also connected to the two input ends of the same differential amplifier circuit.

[0091] Specifically, the fixed resistor at the power supply end of the two fixed resistor branches has the same resistance value as the fixed resistors on the other two branches.

[0092] In some embodiments, the main circuit temperature control circuit and the backup circuit temperature control circuit both include two branches arranged in parallel, one branch includes two groups of resistance circuits arranged in series, and also includes a switching circuit arranged in parallel with the grounding terminal resistance circuit and a voltage stabilizing circuit arranged in parallel, and the other branch includes a freewheeling circuit and a switching circuit arranged in series, and also includes a heating circuit connected in parallel with the freewheeling circuit.

[0093] Specifically, the resistance circuit is a main-backup setting structure, the switching circuit includes a switching diode circuit, the voltage stabilizing circuit includes a voltage stabilizing diode circuit, the freewheeling circuit includes a freewheeling diode circuit, the switching circuit includes a field effect transistor circuit, and the heating circuit includes an inductor circuit and a heating device.

[0094] Working principle of temperature measurement and temperature control circuit:

[0095] like Figures 1 to 4 As shown, a specific description is given by taking an embodiment of the temperature measurement and temperature control circuit shown in the figure:

[0096] Assume that thermistor 11 is placed at the part of the object that needs to be heated, thermistor 13 is placed at the part of the object that can respond to the ambient temperature without being heated, and the heating device in the heating circuit 26 is placed at the part of the object that needs to be heated.

[0097] First, the DC-DC power supply chips 1 and 8 realize the conversion from primary power supply to secondary power supply. The secondary power supply output by the DC-DC power supply chip 1 provides a voltage reference for the voltage divider measurement circuit 2. Figure 2 As shown, the voltage divider measurement circuit outputs three voltage signals, voltage signal 1 is the voltage divider of thermistor 11 in the branch, voltage signal 2 is the voltage divider of thermistor 13 in the branch, thermistors 11 and 13 are of the same model, voltage signal 3 is the voltage divider of fixed resistor 15 in the branch, and the temperature value corresponding to the resistance value of fixed resistor 15 can be obtained according to the resistance-temperature characteristics of thermistors 11 and 13, which is regarded as the reference temperature. Figure 3 As shown, 3 voltage signals are respectively passed through 3 same-direction amplification circuits to obtain 3 amplified voltage signals, while voltage signal 1 and voltage signal 2 are passed through a differential amplification circuit to obtain an amplified voltage signal 4, and the 4 amplified voltage signals are converted into digital signals by an AD sampling circuit and then transmitted to a signal processor for data processing. The voltage change of thermistor 11 relative to the reference temperature is obtained by subtracting voltage signal 3 from voltage signal 1, and the resistance change can be obtained by substituting it into the voltage divider formula. The temperature change can be obtained according to the resistance-temperature characteristic formula, and finally the temperature change is added to the reference temperature to obtain the absolute temperature of the heated part. The purpose of obtaining the absolute temperature according to the voltage change is to eliminate the error caused by the secondary power supply fluctuation and improve the temperature measurement accuracy. Similarly, the absolute temperature of the environment can be obtained by subtracting voltage signal 3 from voltage signal 2. The fixed resistors 10, 12 and 14 have the same resistance value in order to further reduce the error and influence caused by the inconsistent voltage divider resistors, so that the voltage difference signal is closer to the corresponding real temperature difference. According to the amplified voltage signal 4, the relative temperature of the heated part and the environment after eliminating the secondary power supply fluctuation can be directly obtained, so that the signal processor can determine whether to continue heating.

[0098] The temperature measurement circuit adopts a hot backup design, firstly to improve reliability. When one circuit fails, the other circuit can continue to be used. Secondly, the average of the two circuits is used to improve accuracy.

[0099] The secondary power output by the DC-DC power chip 8 provides power for the temperature control circuit 7. Figure 1As shown, the signal processor controls the remote control circuit 9 through the control instruction, and directly controls the prohibition end pin of the DC-DC power chip 8 through the contact of the relay. When the prohibition end pin is suspended, the DC-DC power module 4 works normally; when the prohibition end pin is grounded, the DC-DC power module prohibits output, so the power redundancy cold backup can be realized by controlling the prohibition end pin of the DC-DC power module 4. Thus, the main circuit DC-DC power module and the backup circuit DC-DC power module are set in parallel, and the switching power supply of the two power modules is realized by controlling the prohibition end pin, and then the corresponding main backup temperature control circuit is powered to prevent the problem of heating function failure caused by a problem in one power module or temperature control circuit. Since a large back electromotive force is generated at the moment of power failure of the relay coil in the remote control circuit 9, the back electromotive force will damage the control circuit of the driving end. Therefore, Schottky diodes are connected in reverse parallel at both ends of the relay coil to clamp the coil back electromotive force at the forward conduction voltage of the diode, and the diode is used to realize continuous current, thereby protecting the remote control circuit 9.

[0100] like Figure 4 As shown, the signal processor controls the switching transistor 20 through the switching signal. When the switching signal is at a high level and the base-emitter voltage of the switching transistor is greater than the turn-on voltage, the switching transistor is turned on, and the resistance circuit 2 is short-circuited, that is, the g-pole voltage of the field effect transistor 23 is at a low level, which is not enough to turn on, and the heating circuit is in an open circuit state; when it is at a low level and the base-emitter voltage of the switching transistor is less than the turn-on voltage, the switching transistor is not turned on, and the divided voltage of the resistance circuit 2 is used as the g-pole input voltage. At this time, the gate-source voltage is greater than the turn-on voltage, the field effect transistor 23 is turned on, the heating circuit is turned on, and heating starts.

[0101] The role of the inductor in the heating circuit 26 is to store electrical energy. When the switch state in the circuit changes, the inductor can release or absorb electrical energy to maintain stable operation of the circuit. When the current is disconnected, the inductor element in the circuit will generate a reverse electromotive force due to the self-inductance of the inductor. The Schottky diode 25 is connected in parallel at both ends of the heating circuit 26 to gradually release the energy in the inductor in the form of a continuous current, thereby protecting the heating device in the heating circuit from damage by sudden voltage changes.

[0102] The function of the voltage zener diode 21 is to provide a stable voltage output in the circuit. If the power supply voltage fluctuates or other reasons cause the voltage at each point in the circuit to change, due to the breakdown effect of the voltage zener diode, the reverse voltage is kept basically unchanged within a certain reverse current range, so it can provide a stable voltage output, thereby protecting other components in the circuit from the influence of voltage fluctuations.

[0103] In order to improve the reliability of the temperature control circuit, the resistor circuits 24 and 22 both adopt a method of connecting resistors in parallel. This method is adopted to make the resistors in the parallel branches serve as backup for each other.

[0104] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for limiting purposes. In some embodiments, it will be apparent to those skilled in the art that, unless otherwise expressly noted, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A space temperature measurement and control circuit, characterized in that: The space temperature measurement and control circuit comprises: a DC-DC module, a voltage division measurement circuit, a voltage amplification circuit, an AD sampling circuit, a signal processor, and a temperature control circuit; The first DC-DC module is electrically connected to the voltage division measurement circuit, the voltage division measurement circuit is electrically connected to the voltage amplifier circuit, the voltage amplifier circuit is electrically connected to the AD sampling circuit, the AD sampling circuit is electrically connected to the signal processor, and the second end of the signal processor is electrically connected to the temperature control circuit; the voltage division measurement circuit is provided with multiple thermistors and at least one fixed resistor; The second DC-DC module is electrically connected to the other end of the temperature control circuit, the first DC-DC module is connected to a primary power supply, and the second DC-DC module is connected to a primary power supply; The primary power supply enters the DC-DC module for processing to form a secondary power supply. The secondary power supply enters the voltage division measurement circuit and is divided into multiple paths. The secondary power supply forms voltage signals of corresponding numbers through multiple thermistors. The secondary power supply forms a reference voltage signal through at least one fixed resistor. The absolute temperature is determined by the multiple voltage signals and the reference voltage signal to eliminate errors caused by fluctuations in the secondary power supply.

2. A space temperature measurement and control circuit as claimed in claim 1, characterized in that: The space temperature measurement and control circuit also includes a backup circuit, which includes: a first backup DC-DC module, a second voltage division measurement circuit, a second voltage amplification circuit, and a second backup DC-DC module; The first backup DC-DC module is electrically connected to the voltage division measurement circuit, the voltage division measurement circuit is electrically connected to the second voltage amplification circuit, and the second voltage amplification circuit is electrically connected to the AD sampling circuit; The third terminal of the signal processor is electrically connected to the second temperature control circuit, and the second temperature control circuit is electrically connected to the second backup DC-DC module.

3. A space temperature measurement and control circuit as claimed in claim 2, characterized in that: The space temperature measurement and control circuit also includes: a control instruction module and a remote control circuit; The fourth terminal of the signal processor is electrically connected to the control instruction, the control instruction is electrically connected to the remote control circuit, and the remote control circuit is used to control the second DC-DC module and / or the second backup DC-DC module.

4. A space temperature measurement and control circuit as claimed in claim 1, characterized in that: The voltage amplification circuit comprises: a lead-in amplification circuit and a differential amplification circuit; The first output terminal of the voltage division measurement circuit is electrically connected to the first differential amplifier circuit, and the second output terminal is electrically connected to the first differential amplifier circuit; The first output terminal of the second voltage-dividing measurement circuit is electrically connected to the second differential amplifier circuit, and the second output terminal is electrically connected to the second differential amplifier circuit.

5. A space temperature measurement and control circuit as claimed in claim 1, characterized in that: The voltage division measurement circuit comprises: multiple thermistors and at least one fixed resistor; Each thermistor is connected in series with a preset fixed resistor, and multiple thermistors are connected in parallel; At least one fixed resistor is connected in series with a preset fixed resistor, and at least one fixed resistor is connected in parallel with the multi-channel thermistor.

6. A space temperature measurement and control circuit as claimed in claim 1, characterized in that: The voltage amplification circuit comprises: a common-direction amplification circuit and a differential amplification circuit; The input end leading to the amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit; the input end of the differential amplifier circuit is electrically connected to the second output end of the voltage divider measurement circuit.

7. A space temperature measurement and control circuit as claimed in claim 6, characterized in that: The voltage amplifier circuit comprises: a first same-direction amplifier circuit, a second same-direction amplifier circuit, a third same-direction amplifier circuit, and a differential amplifier circuit; The input end of the first unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, the input end of the second unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, the input end of the third unidirectional amplifier circuit is electrically connected to the first output end of the voltage divider measurement circuit, and the differential amplifier circuit is electrically connected to the second output end of the voltage divider measurement circuit.

8. A space temperature measurement and control circuit as claimed in claim 1, characterized in that: The temperature control circuit comprises: a first resistance circuit, a Schottky diode, a heating circuit, a field effect transistor, a switching transistor, a voltage regulator diode, and a second resistance circuit; The input end of the first resistance circuit, the input end of the Schottky diode, and the input end of the heating circuit are respectively connected to the input end of the temperature control circuit; the output end of the first resistance circuit is respectively connected to the switching transistor, the voltage-stabilizing diode, the resistance circuit, and the field-effect transistor; the output end of the Schottky diode and the output end of the heating circuit are respectively connected to the second input end of the field-effect transistor; the output ends of the switching transistor, the voltage-stabilizing diode, the second resistance circuit, and the field-effect transistor are respectively connected to the output end of the temperature control circuit.

9. A space temperature measurement and control device, characterized in that: The spatial temperature measurement and control device is arranged in the filter wheel device and is used to heat the calibration plate of the filter wheel device. The spatial temperature measurement and control circuit according to any one of claims 1 to 8 is arranged in the spatial temperature measurement and control device.

10. A filter wheel device, characterized in that: The filter wheel device is provided with a space temperature control and temperature measurement circuit as described in any one of claims 1 to 8.

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