Mining double-channel temperature measurement sensor system with calibration-free function and measurement method

Abstract

The invention relates to a mining double-channel temperature measurement sensor system with a calibration-free function and a measurement method, and belongs to the field of temperature measurement. The system comprises a high-precision time measurement unit, two platinum resistors, an ARM processor and a bus communication circuit. The high-precision time measuring unit is respectively connected with the two platinum resistors and is used for respectively measuring the charging and discharging time of the two platinum resistors and calculating the resistance values of the platinum resistors according to the two charging and discharging time so as to obtain the measured temperature; the ARM processor communicates with the high-precision time measurement unit through the bus communication circuit, and the temperature measured by the platinum resistor is calibrated. The platinum resistor temperature measuring device is high in measuring precision and low in power consumption and cost, has few peripheral circuits, does not need to construct a constant current source circuit or a balanced bridge circuit, an operational amplifier circuit and an analog-to-digital conversion circuit, and can measure the temperatures of the two platinum resistors at the same time without calibration.

Description

Technical Field

[0001] The invention belongs to the field of temperature measurement, and relates to a mining dual-path temperature measurement sensor system with a calibration-free function and a measurement method. Background Art

[0002] Platinum resistance temperature measurement is widely used in mining temperature sensors. The traditional platinum resistance temperature measurement circuit first needs to build a constant current source circuit or a Wheatstone bridge circuit, then amplify the weak voltage signal through a precision operational amplifier, and finally use a processor with an analog-to-digital converter (ADC) to collect and calibrate the voltage to obtain the measured temperature.

[0003] Although this temperature measurement circuit is simple and reliable, it requires precision operational amplifiers and ADCs to participate in the measurement, resulting in a large number of discrete components, large superposition errors, and poor input and output consistency of each set of equipment. If the coefficients are not corrected, there will be a large error with the standard value, which will lead to a large amount of correction work before batch products leave the factory.

[0004] Therefore, it is urgent to develop a platinum resistance temperature sensor with simple circuit, low cost and high measurement accuracy to solve the above problems. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a mining dual-channel temperature measurement sensor system and a measurement method with a calibration-free function, which can reduce peripheral circuits while maintaining high measurement accuracy.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A dual-channel temperature sensor system for mining with calibration-free function, comprising a high-precision time measurement unit, two platinum resistors, an ARM processor and a bus communication circuit;

[0008] The high-precision time measurement unit is connected to two platinum resistors respectively, and the charge and discharge time of the two platinum resistors is measured respectively, and the resistance value of the platinum resistor is calculated according to the two charge and discharge times, so as to obtain the measured temperature;

[0009] The ARM processor communicates with the high-precision time measurement unit through a bus communication circuit (SPI communication protocol) to calibrate the temperature measured by the platinum resistance.

[0010] Furthermore, the system also includes a power supply circuit, a data display circuit and a key circuit; the power supply circuit is used to supply power to the bus communication circuit, the ARM processor and the high-precision time measurement unit; the data display circuit and the key circuit are respectively connected to the ARM processor, the data display circuit is used to display the platinum resistance temperature calibrated by the ARM processor, and the key circuit is used to start the system operation.

[0011] Furthermore, the measurement method of the system is specifically as follows: first, the high-precision time measurement unit is initialized and calibrated, and the ARM processor determines whether the calibration coefficient is greater than 0.9 and less than 1.1. If so, the calibration is considered successful, otherwise it is recalibrated; secondly, the ARM processor sends 2-way temperature measurement commands to perform temperature measurement, and software filtering is performed to obtain 2-way filtered platinum resistance temperature values; finally, the 2-way filtered temperature data are multiplied by the calibration coefficient to obtain the calibrated temperature data, and then the 2-way temperature data are displayed and transmitted via the data bus.

[0012] Furthermore, the calibration coefficient of the high-precision time measurement unit is automatically completed by the ARM processor sending a calibration instruction to the high-precision time measurement unit (ie, the time chip).

[0013] The beneficial effect of the present invention is that the system of the present invention charges and discharges two platinum resistors, uses a high-resolution time measurement unit to measure the charge and discharge time of the two platinum resistors respectively, and calculates the resistance of the platinum resistor according to the two charge and discharge times, thereby obtaining the measured temperature. The measurement method of the system of the present invention has high measurement accuracy and few peripheral circuits. It is not necessary to construct a constant current source circuit or a balanced bridge circuit, nor is it necessary to construct an operational amplifier circuit and an analog-to-digital conversion circuit. The temperature of two platinum resistors can be measured simultaneously without calibration, and the power consumption and cost are low.

[0014] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0016] Figure 1 This is a structural block diagram of the dual-path temperature sensor system for mining of the present invention;

[0017] Figure 2 This is a measurement flow chart of the dual-path temperature sensor system for mining of the present invention. DETAILED DESCRIPTION

[0018] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0019] See also Figure 1-2 The embodiment of the present invention provides a dual-channel temperature sensor system for mining with a calibration-free function, which is composed of a power supply circuit, a bus communication circuit, a key circuit, a data display circuit, an ARM processor, a high-precision time measurement unit and two platinum resistors. Figure 1 As shown in the figure, the high-precision time measurement unit is usually composed of TDC-GP22, which communicates with the ARM processor through the SPI protocol; the platinum resistance is usually composed of PT1000, which is directly connected to the time measurement unit.

[0020] The measurement method flow of this system is as follows Figure 2 As shown, first, the time measurement unit is initialized and calibrated, and it is determined whether the calibration coefficient is greater than 0.9 and less than 1.1, then the calibration is considered successful, otherwise it is recalibrated; secondly, 2-way temperature measurement commands are sent to perform temperature measurement, and software filtering is performed to obtain 2-way filtered platinum resistance temperature values; finally, the 2-way filtered temperature data are multiplied by the calibration coefficient to obtain the calibrated temperature data, and then the 2-way temperature data are displayed and transmitted via the data bus.

[0021] The system of the present invention has few peripheral circuits, and does not need to construct a constant current source circuit or a balanced bridge circuit, nor does it need to construct an operational amplifier circuit and an analog-to-digital conversion circuit. It can measure the temperature of two platinum resistors PT1000 at the same time without calibration, and has low power consumption and cost.

[0022] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A dual-channel temperature sensor system for mining with calibration-free function, characterized in that: The system includes a high-precision time measurement unit, two platinum resistors, an ARM processor and a bus communication circuit; The high-precision time measurement unit is connected to two platinum resistors to measure the charge and discharge time of the two platinum resistors respectively, and the resistance value of the platinum resistor is calculated according to the two charge and discharge times, thereby obtaining the measured temperature; The ARM processor communicates with the high-precision time measurement unit through a bus communication circuit to calibrate the temperature measured by the platinum resistance.

2. The dual-path temperature sensor system for mining according to claim 1 is characterized in that: The system also includes a power supply circuit, a data display circuit and a key circuit; the power supply circuit is used to supply power to a bus communication circuit, an ARM processor and a high-precision time measurement unit; the data display circuit and the key circuit are respectively connected to the ARM processor, the data display circuit is used to display the platinum resistance temperature calibrated by the ARM processor, and the key circuit is used to start the system.

3. The dual-path temperature sensor system for mining according to claim 1 or 2, characterized in that: The measurement method of the system is as follows: first, the high-precision time measurement unit is initialized and calibrated, and the ARM processor determines whether the calibration coefficient is greater than 0.9 and less than 1.

1. If so, the calibration is considered successful, otherwise recalibration is performed; Secondly, the ARM processor sends 2-way temperature measurement commands to perform temperature measurement, and then performs software filtering to obtain the temperature values ​​of the 2-way filtered platinum resistors. Finally, the 2-way filtered temperature data are multiplied by the calibration coefficient to obtain the calibrated temperature data, and then the 2-way temperature data are displayed and transmitted via the data bus.

4. The dual-path temperature sensor system for mining according to claim 3 is characterized in that: The calibration coefficient of the high-precision time measurement unit is automatically completed by sending calibration instructions through the ARM processor.

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