CN206146549U - Be applied to temperature measuring means of solar energy light and heat experimental system - Google Patents
Be applied to temperature measuring means of solar energy light and heat experimental system Download PDFInfo
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- CN206146549U CN206146549U CN201621154903.6U CN201621154903U CN206146549U CN 206146549 U CN206146549 U CN 206146549U CN 201621154903 U CN201621154903 U CN 201621154903U CN 206146549 U CN206146549 U CN 206146549U
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Abstract
The utility model discloses a be applied to temperature measuring means of solar energy light and heat experimental system, it includes the temperature signal processing module, the MCU treater, the host computer, the temperature signal processing module includes the platinum resistor temperature sensor constant current source circuit, signal conditioning circuit and AD converting circuit, the platinum resistor temperature sensor constant current source circuit loops through signal conditioning circuit and AD converting circuit is connected with the MCU treater, the MCU treater is connected with the liquid crystal display who is used for visual display temperature value, a data storage module for temperature data is spare, a power module that the acousto -optic warning module of warning when is used for the temperature to exceed alarm threshold value suggestion and supplying power for the MCU treater, the output of MCU treater passes through the serial port connection host computer, the host computer shows the temperature curve in real time and provides data derives the interface. The utility model discloses a solar energy light and heat experimental system thermal behavior detects and the aassessment of efficiency index provides convenient testing ring border, and the precision is high, measuring range is wide.
Description
Technical field
This utility model is related to a kind of temperature testing device, more particularly to a kind of solar energy optical-thermal experimental system of being applied to
Temperature testing device.
Background technology
To help Students ' Learning and understanding the principle of solar energy hot systems and the ability of practice of starting of raising engineer applied,
Need to develop a set of solar energy optical-thermal experiment teaching system, the system requirements realizes at a lower cost practical training project requirement temperature
Degree parameters precision is high, the requirement that temperature measurement range is wide.More to the research of High Accuracy Temperature Measure System both at home and abroad, method is each
It is different, Tao Qingdong's etc.《Scaling method based on SCM Temperature Measure》Electricity is obtained as temperature element using thermocouple in one text
Kinetic potential, carries out Function Fitting twice and obtains temperature after amplification by A/D conversions, and program stability is high, but precision only reaches ± 0.2
℃；Wen Bo etc. exists《Automatic water temperature controller based on increment type PID algorithm is designed》In with DS18B20 as temperature element, use
Increment type PID algorithm realizes that measurement error is within 0.5 DEG C in the range of 10 DEG C～80 DEG C；Fang Yixi's etc.《Based on PT1000
High Accuracy Temperature Measure System》It is, with platinum resistance as temperature element, to be driven in method and host computer using three-wire system constant-current source and drawn
Enter MLS numerical algorithms and greatly reduce measurement error, Experimental measurement error is not more than 0.01 DEG C in 10 DEG C～70 DEG C.It is several above
Plant the demand that temperature measurement schemes do not meet solar energy hot systems in measurement range or certainty of measurement, it is impossible to be applied to too
In positive energy photo-thermal experimental system.
The content of the invention
The purpose of this utility model be overcome at present low price position measuring sensor thermometric scope compared with
A kind of low problem of narrow, temperature measurement accuracy, there is provided temperature testing device for being applied to solar energy optical-thermal experimental system.
The technical solution adopted in the utility model is：
A kind of temperature testing device for being applied to solar energy optical-thermal experimental system, it includes processes temperature signal module, MCU
Processor, host computer, processes temperature signal module includes platinum resistance temperature sensor constant current source driving circuit, signal conditioning circuit
With A/D change-over circuits, temperature signal connection platinum resistance temperature sensor constant current source driving circuit, platinum resistance temperature sensor constant current
Source driving circuit passes sequentially through signal conditioning circuit and A/D change-over circuits are connected with MCU processors, the MCU processors connection
There are LCDs, data memory module, sound and light alarm module and power module, LCDs are used for displays temperature number directly perceived
Value, data memory module is used for the backup of temperature data, and sound and light alarm module is used for warning when temperature exceedes alarm threshold value and carries
Show, power module is powered for MCU processors, the outfan of MCU processors connects host computer by serial ports, and host computer shows in real time
Temperature curve simultaneously provides data export interface.
Described platinum resistance temperature sensor is PT1000 temperature sensors
Described platinum resistance temperature sensor constant current source driving circuit includes：ADR421 reference voltage source U22, OPA277 are transported
Put U10, U11, resistance R200, R201, R202, R203, R204, R205, adjustable resistance RP1, RP2 and electric capacity C200, C201,
C202；Electric capacity C202 connects reference voltage output, and it is defeated in the same direction that reference voltage source U22 output Jing resistance R201 connect OPA277 amplifiers U11
Enter the outfan and reverse input end of end, resistance R201 and R200 series connection OPA277 amplifiers U10；OPA277 amplifiers U11 it is anti-
To input Jing resistance R202 ground connection, Jing resistance R203 connect the outfan of OPA277 amplifiers U11；The input in the same direction of amplifier U10
U3 Jing potentiometers adjust the outfan that the reference resistance of resistance composition connects OPA277 amplifiers U11.
Described signal conditioning circuit includes：OPA277 amplifiers U16, U17, platinum resistance PT1000, resistance R230, R231,
R232, R233 and adjustable resistance RP7, RP8；One terminal of the current input terminal of reference current input platinum resistance PT1000, platinum electricity
The another terminal of the current input terminal of resistance PT1000 connects the input in the same direction of OPA277 amplifiers U16, the reverse input of amplifier U16
The outfan of end connection amplifier U16, platinum resistance PT1000 current output terminal connects respectively one end of adjustable resistance RP7 and OPA277
Amplifier U17 input in the same direction, the other end of adjustable resistance RP7 connects adjustable resistance RP8 respectively and one end of resistance R230 is common
The other end ground connection of the zero degree resistance of composition, adjustable resistance RP8 and resistance R230, the reverse input end of amplifier U17 connects respectively
One end ground connection of resistance R232 and resistance R233, the other end ground connection of resistance R232, other end connection amplifier U17 of resistance R233
Outfan, OPA277 amplifier U16, U17 output voltages are respectively connected to an input of described A/D change-over circuits.
Described A/D change-over circuits adopt 16 high accuracy TM7705A/D transducers.
Described LCDs adopt model SSD1963QL9.
, using buzzer and LED, LED quick flashings when temperature exceedes alarm threshold value are while buzzing for described sound and light alarm module
Device sounding, otherwise LED slow flash and buzzer not sounding.
Described data memory module adopts Micro SD.
Described MCU processors adopt STM32F103RBT6.
This utility model adopts above technical scheme, MCU processors to gather the temperature Jing after processes temperature signal resume module
Degree signal, being calculated temperature and be sent to touching display screen using method of least square carries out the displaying directly perceived of Temperature numerical, data storage
Module realizes that temperature data is backed up, and sound and light alarm module carries out alarm when real time temperature exceedes alarm threshold value, and by string
Mouthful upload to host computer and carry out real time temperature curve and show and provide data export interface.The beneficial effects of the utility model are：
First, using Differential Input method, the difference of platinum resistance pressure drop and zero degree resistance drop is carried out into analog digital conversion, introduce least square
Method carries out four fittings of segmentation, makes temperature measuring equipment that there is the characteristics of temperature measurement range is wide, temperature measurement accuracy is high to be provided simultaneously with
Stronger capacity of resisting disturbance.Second, sound and light alarm is carried out during temperature anomaly, make user find and solve that temperature anomaly is asked in time
Topic.3rd, SD card backup is carried out to temperature data, improve the reliability of Research on Automatic Measuring System of Temperature.4th, using liquid crystal display screen and upper
Machine shows temperature data, there is provided easily test environment.
Description of the drawings
This utility model is described in further details below in conjunction with the drawings and specific embodiments；
Fig. 1 is a kind of structural representation of the temperature testing device for being applied to solar energy optical-thermal experimental system of this utility model
Figure；
Fig. 2 is a kind of platinum resistance temperature of the temperature testing device for being applied to solar energy optical-thermal experimental system of this utility model
Sensor constant current source driving circuit schematic diagram；
Fig. 3 is electric for a kind of signal condition of temperature testing device for being applied to solar energy optical-thermal experimental system of this utility model
Road schematic diagram；
Fig. 4 is electric for a kind of A/D conversions of temperature testing device for being applied to solar energy optical-thermal experimental system of this utility model
Road schematic diagram.
Fig. 5 shows for a kind of workflow of the temperature testing device for being applied to solar energy optical-thermal experimental system of this utility model
It is intended to；
Specific embodiment
As shown in one of Fig. 1-5, this utility model discloses a kind of temperature test for being applied to solar energy optical-thermal experimental system
Device, it includes processes temperature signal module, MCU processors, host computer, and processes temperature signal module is passed including platinum resistance temperature
Sensor constant current source driving circuit, signal conditioning circuit and A/D change-over circuits, temperature signal connection platinum resistance temperature sensor constant current
Source driving circuit, platinum resistance temperature sensor constant current source driving circuit pass sequentially through signal conditioning circuit and A/D change-over circuits with
MCU processors connect, and the MCU processors are connected with LCDs, data memory module, sound and light alarm module and power supply mould
Block, LCDs are used for displays temperature numerical value directly perceived, and data memory module is used for the backup of temperature data, sound and light alarm module
Exceed alarm during alarm threshold value for temperature, power module is powered for MCU processors, the outfan of MCU processors leads to
Serial ports connection host computer is crossed, the real-time displays temperature curve of host computer simultaneously provides data export interface.
Described platinum resistance temperature sensor is PT1000 temperature sensors
As shown in Fig. 2 described platinum resistance temperature sensor constant current source driving circuit includes：ADR421 reference voltage sources
U22, OPA277 amplifier U10, U11, resistance R200, R201, R202, R203, R204, R205, adjustable resistance RP1, RP2 and electric capacity
C200, C201, C202, electric capacity C200, C201 are in parallel between the both positive and negative polarity of power supply, the both positive and negative polarity difference of power supply
The input of electric capacity C202 is accessed, electric capacity C202 connects reference voltage output, and reference voltage source U22 output Jing resistance R201 connect
OPA277 amplifiers U11 input in the same direction, outfans and reversely input of the resistance R201 with R200 series connection OPA277 amplifiers U10
End；The reverse input end Jing resistance R202 ground connection of OPA277 amplifiers U11, Jing resistance R203 connect the outfan of OPA277 amplifiers U11；
Connect one end of resistance R204, the other end of resistance R204 as the input U3 in the same direction of amplifier U10 of reference current outfan
Connect the reference resistance that one end of resistance R205 and regulation resistance RP2 is constituted, resistance R205 and tune respectively through adjusting resistance RP1
The outfan of another termination OPA277 amplifier U11 of economize on electricity resistance RP2.
As shown in Figure 3 or Figure 4, described signal conditioning circuit includes：OPA277 amplifiers U16, U17, platinum resistance PT1000,
Resistance R230, R231, R232, R233 and adjustable resistance RP7, RP8；Wherein PT2-1 is current input terminal, the PT2-2 of PT1000
For the current output terminal of PT1000, a terminal of the current input terminal of reference current input platinum resistance PT1000, platinum resistance
The another terminal of the current input terminal of PT1000 connects the input in the same direction of OPA277 amplifiers U16, the reverse input end of amplifier U16
The outfan of connection amplifier U16, platinum resistance PT1000 current output terminal connects respectively one end of adjustable resistance RP7 and OPA277 fortune
U17 inputs in the same direction are put, the other end of adjustable resistance RP7 connects respectively the common structure in one end of adjustable resistance RP8 and resistance R230
Into zero degree resistance, the other end ground connection of adjustable resistance RP8 and resistance R230, the reverse input end of amplifier U17 connects respectively electricity
One end ground connection of resistance R232 and resistance R233, the other end ground connection of resistance R232, other end connection amplifier U17 of resistance R233
Outfan, OPA277 amplifier U16, U17 output voltages are respectively connected to an input of described A/D change-over circuits.Distinguish
Connect 6 feet and 11 feet of A/D converter TM7705.
The precision and stability of the stability decision systems of test electric current, is tested electric current and is added by two of PT1000
Line, by the resistance signal of temperature change measurable voltage signal is converted into, and by the two other line of PT1000 voltage is measured
Signal.PT1000 is connected with zero degree resistance (size is equal to the zero degree resistance of platinum resistance), after amplifier is adjusted, by platinum resistance
The difference of pressure drop and zero degree resistance drop sends into the differential input end of TM7705, and direct measurement platinum resistance voltage is with respect to during zero degree
Variable quantity, the method can reach very high certainty of measurement.
Described A/D change-over circuits adopt 16 high accuracy TM7705A/D transducers.The system temperature measurement accuracy design object
For 0.1 DEG C, need to select ADC digits according to system requirements when ADC is selected.Inquiry PT1000 phasing meters are learnt at 0 DEG C～90 DEG C
The Ω of platinum resistance resistance minimum change 0.112, the platinum in 0 DEG C～90 DEG C temperature ranges during 0.1 DEG C of temperature change in temperature range
Resistance maximum variable quantity is obtained as 347.069 Ω by look-up table, then can calculate the design accuracy of the system requirement：
The precision in theory of 14 ADC is up to 0.000061, but because ADC itself has DNL errors, offset error etc. to cause
The available accuracy of 14 ADC is unable to reach 0.000061, in order to leave error margin, from the high accuracy of 16 during system design
ADC：TM7705.
Described LCDs adopt model SSD1963QL9.
, using buzzer and LED, LED quick flashings when temperature exceedes alarm threshold value are while buzzing for described sound and light alarm module
Device sounding, otherwise LED slow flash and buzzer not sounding.
Described data memory module adopts Micro SD.
Described MCU processors adopt STM32F103RBT6.
Using the workflow of present invention during said apparatus as shown in figure 5, being described as follows：
Step 501：The peripheral hardware resources such as starter, initialization MCU, LCD module, SD card module and serial port module, read
Operational factor and alarm threshold value etc..
Step 502：Initialization temperature data acquisition task related resource, timing acquiring temperature data has timed outIf
It is to carry out execution step 503.
Step 503：In same temperature point continuous sampling 10 times, digital filtering process is carried out to each sampled point, reject 10
Maximum and minima in individual data, the final sampled value of the temperature sampling point takes the meansigma methodss of remaining 8 data.
Step 504：The relational expression coefficient of every section of AD value and temperature is fitted for four times using method of least square and micro- place is stored in
In reason device MCU, select suitable coefficient to substitute into formula according to the corresponding temperature range of AD values and calculate acquisition real time temperature.
Step 505：Detect whether as alert dataIf it is execution step 506.
Step 506：Sound and light alarm is carried out, LED quick flashings are while buzzer sounding.
Step 507：Temperature data carries out SD card backup and is shown while being sent to liquid crystal display screen.
Step 508：Detect whether to call time on temperature dataIf it is execution step 509.
Step 509：Packet uploads to host computer by serial ports.
Step 510：Terminate.
This utility model adopts above technical scheme, MCU processors to gather the temperature Jing after processes temperature signal resume module
Degree signal, being calculated temperature and be sent to touching display screen using method of least square carries out the displaying directly perceived of Temperature numerical, data storage
Module realizes that temperature data is backed up, and sound and light alarm module carries out alarm when real time temperature exceedes alarm threshold value, and by string
Mouthful upload to host computer and carry out real time temperature curve and show and provide data export interface.The beneficial effects of the utility model are：
First, using Differential Input method, the difference of platinum resistance pressure drop and zero degree resistance drop is carried out into analog digital conversion, introduce least square
Method carries out four fittings of segmentation, makes temperature measuring equipment that there is the characteristics of temperature measurement range is wide, temperature measurement accuracy is high to be provided simultaneously with
Stronger capacity of resisting disturbance.Second, sound and light alarm is carried out during temperature anomaly, make user find and solve that temperature anomaly is asked in time
Topic.3rd, SD card backup is carried out to temperature data, improve the reliability of Research on Automatic Measuring System of Temperature.4th, using liquid crystal display screen and upper
Machine shows temperature data, there is provided easily test environment.
Claims (6)
1. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system, it is characterised in that：It is included at temperature signal
Reason module, MCU processors, host computer, processes temperature signal module includes platinum resistance temperature sensor constant current source driving circuit, letter
Number modulate circuit and A/D change-over circuits, temperature signal connection platinum resistance temperature sensor constant current source driving circuit, platinum resistance temperature
Sensor constant current source driving circuit passes sequentially through signal conditioning circuit and A/D change-over circuits are connected with MCU processors, the MCU
Processor is connected with LCDs, data memory module, sound and light alarm module and power module, and LCDs are used for directly perceived
Displays temperature numerical value, data memory module is used for the backup of temperature data, and sound and light alarm module is used for temperature and exceedes alarm threshold value
When alarm, power module powers for MCU processors, and the outfan of MCU processors connects host computer by serial ports, upper
The real-time displays temperature curve of machine simultaneously provides data export interface.
2. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system according to claim 1, it is characterised in that：
Described platinum resistance temperature sensor is PT1000 temperature sensors.
3. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system according to claim 1, it is characterised in that：
Described platinum resistance temperature sensor constant current source driving circuit includes：ADR421 reference voltage source U22, OPA277 amplifiers U10,
U11, resistance R200, R201, R202, R203, R204, R205, adjustable resistance RP1, RP2 and electric capacity C200, C201, C202；Electricity
Hold C202 and connect reference voltage output, reference voltage source U22 output Jing resistance R201 connect OPA277 amplifiers U11 input in the same direction, electricity
The outfan and reverse input end of resistance R201 and R200 series connection OPA277 amplifiers U10；The reverse input end of OPA277 amplifiers U11
Jing resistance R202 is grounded, and Jing resistance R203 connect the outfan of OPA277 amplifiers U11；The input U3 Jing current potentials in the same direction of amplifier U10
Device adjusts the outfan that the reference resistance of resistance composition connects OPA277 amplifiers U11.
4. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system according to claim 1, it is characterised in that：
Described signal conditioning circuit includes：OPA277 amplifiers U16, U17, platinum resistance PT1000, resistance R230, R231, R232, R233
With adjustable resistance RP7, RP8；One terminal of the current input terminal of reference current input platinum resistance PT1000, platinum resistance PT1000
The another terminal of current input terminal connects the input in the same direction of OPA277 amplifiers U16, and the reverse input end of OPA277 amplifiers U16 connects
Connect the outfan of OPA277 amplifiers U16, platinum resistance PT1000 current output terminal connect respectively one end of adjustable resistance RP7 and
OPA277 amplifiers U17 input in the same direction, the other end of adjustable resistance RP7 connects respectively the one of adjustable resistance RP8 and resistance R230
The zero degree resistance that collectively forms of end, the other end ground connection of adjustable resistance RP8 and resistance R230, OPA277 amplifiers U17 it is reverse defeated
Enter one end ground connection that end connects respectively resistance R232 and resistance R233, the other end of resistance R232 is grounded, and resistance R233's is another
The outfan of end connection OPA277 amplifiers U17, OPA277 amplifier U16, U17 output voltages are respectively connected to described A/D conversion electricity
One input on road.
5. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system according to claim 1, it is characterised in that：
Described A/D change-over circuits adopt 16 high accuracy TM7705A/D transducers.
6. a kind of temperature testing device for being applied to solar energy optical-thermal experimental system according to claim 1, it is characterised in that：
Described sound and light alarm module using buzzer and LED, LED quick flashings buzzer sounding simultaneously when temperature exceedes alarm threshold value,
Otherwise LED slow flash and buzzer not sounding.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201621154903.6U CN206146549U (en) | 2016-10-31 | 2016-10-31 | Be applied to temperature measuring means of solar energy light and heat experimental system |
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| CN201621154903.6U CN206146549U (en) | 2016-10-31 | 2016-10-31 | Be applied to temperature measuring means of solar energy light and heat experimental system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107610570A (en) * | 2017-11-03 | 2018-01-19 | 福建师范大学 | Solar energy optical-thermal experimental real-training apparatus and operating method |
| CN110243486A (en) * | 2019-07-04 | 2019-09-17 | 上海申矽凌微电子科技有限公司 | Full temperature high-precision temperature sensor-based system, method and medium |
| CN112327133A (en) * | 2020-10-20 | 2021-02-05 | 南京尚孚电子电路有限公司 | High-temperature heat dissipation test system for aluminum-based circuit board and test method thereof |
| WO2022105247A1 (en) * | 2020-11-20 | 2022-05-27 | 华润微集成电路(无锡)有限公司 | Circuit structure for achieving multiplexing of pin of circuit |
-
2016
- 2016-10-31 CN CN201621154903.6U patent/CN206146549U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107610570A (en) * | 2017-11-03 | 2018-01-19 | 福建师范大学 | Solar energy optical-thermal experimental real-training apparatus and operating method |
| CN110243486A (en) * | 2019-07-04 | 2019-09-17 | 上海申矽凌微电子科技有限公司 | Full temperature high-precision temperature sensor-based system, method and medium |
| CN110243486B (en) * | 2019-07-04 | 2021-01-08 | 上海申矽凌微电子科技有限公司 | Full-temperature high-precision temperature sensing system, method and medium |
| CN112327133A (en) * | 2020-10-20 | 2021-02-05 | 南京尚孚电子电路有限公司 | High-temperature heat dissipation test system for aluminum-based circuit board and test method thereof |
| WO2022105247A1 (en) * | 2020-11-20 | 2022-05-27 | 华润微集成电路(无锡)有限公司 | Circuit structure for achieving multiplexing of pin of circuit |
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