Fixed detector on-line monitoring device

Abstract

The utility model relates to the technical field of detection devices, in particular to a fixed detector on-line monitoring device which comprises a current acquisition module, a voltage acquisition module, an A / D conversion module, a central processing unit, a temperature and humidity sensor, an alarm controller and an alarm. The current acquisition module and the voltage acquisition module are respectively connected to the central processing unit through the A / D conversion module, the temperature and humidity sensor and the alarm controller are respectively connected with the central processing unit, and the alarm is connected with the alarm controller. The fixed detector on-line monitoring device can detect the concentration of combustible gas and toxic gas in real time, match the concentration with the gas concentration corresponding to the current environment temperature and humidity, monitor the running state of the fixed detector in real time, calibrate the fixed detector in real time, and improve the detection accuracy. The safety in the natural gas production process is improved, and the safety risk is reduced.

Description

A fixed detector online monitoring device Technical Field

[0001] This utility model relates to the field of detection device technology, specifically to a fixed online monitoring device for a detector. Background Technology

[0002] In the natural gas production process, the detection of combustible and toxic gases is a crucial step, directly impacting the safety of natural gas production. Combustible and toxic gases are detected in real-time using instruments, and their operation is monitored in real-time by monitoring devices. Existing detection and monitoring devices typically store standard gas concentration ranges at room temperature in their central processing units, and this range remains constant. In certain special conditions, such as at higher temperatures, the likelihood of safety accidents is much higher than at room temperature, meaning that combustible gases may still ignite even at lower concentrations. Constantly comparing the collected concentration information of combustible or toxic gases to the standard gas concentration range at room temperature to determine whether to issue an alarm could potentially increase safety hazards.

[0003] In addition, after a certain period of use, the gas concentration information collected by the detector may deviate beyond the allowable error range. Therefore, the detector needs to be calibrated. In the existing technology, the detector is often calibrated manually on a regular annual basis. However, this method is prone to problems such as untimely calibration and inaccurate detection of gas concentration. Summary of the Invention

[0004] This invention aims to address the shortcomings of existing technologies by providing a fixed online monitoring device that can detect the concentration of combustible and toxic gases in real time and match them with the gas concentration corresponding to the current ambient temperature and humidity. It can also monitor the operating status of the fixed detector in real time and calibrate the fixed detector in real time, thereby improving the safety of the natural gas production process and reducing safety risks.

[0005] The technical solution adopted in this utility model is as follows: a fixed online monitoring device for a detector, comprising a current acquisition module, a voltage acquisition module, an A / D conversion module, a central processing unit, a temperature and humidity sensor, an alarm controller, and an alarm; the current acquisition module and the voltage acquisition module are both connected to the central processing unit through the A / D conversion module, the temperature and humidity sensor and the alarm controller are both connected to the central processing unit, and the alarm is connected to the alarm controller; the detector is connected to the current acquisition module, the voltage acquisition module, and the central processing unit respectively.

[0006] In one possible implementation, the fixed detector online monitoring device further includes a remote transmission module connected to a central processing unit.

[0007] In one possible implementation, the fixed detector online monitoring device further includes a loop calibration module, which is connected to the central processing unit, the detector, and the voltage acquisition module, respectively, and is used to calibrate the output of the detector.

[0008] Furthermore, the loop calibration module includes an isolation submodule, a reference voltage submodule, a multi-stage filtering submodule, and a voltage-to-current conversion submodule. The input terminal of the isolation submodule is connected to the central processing unit, the output terminal of the isolation submodule is connected to the input terminal of the reference voltage submodule, the output terminal of the reference voltage submodule is connected to the input terminal of the multi-stage filtering submodule, the output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-to-current conversion submodule, and the output terminal of the voltage-to-current conversion submodule is connected to a detector.

[0009] Furthermore, the isolation submodule includes a first chip U1, and the reference voltage submodule includes a second chip U2. The pulse signal generated by the central processing unit is connected to the input pin of U1 via resistor R1. The output pin of U1 is connected to the input pin of U2 via resistor R2. The output pin of U2 is connected to the input terminal of the multi-stage filtering submodule after being divided by resistors R3 and R4. The output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-current conversion submodule. The output terminal of the voltage-current conversion submodule is connected to the detector.

[0010] Furthermore, the multi-stage filtering submodule includes a four-stage filtering circuit consisting of capacitor C1 and resistor R5, capacitor C2 and resistor R6, capacitor C3 and resistor R7, and capacitor C4 and resistor R8.

[0011] Furthermore, the voltage-to-current conversion submodule includes an integrated operational amplifier and a MOS field-effect transistor. The MOS field-effect transistor includes a gate (G), a source (S), and a drain (D). The output terminal of the integrated operational amplifier is connected to the gate (G) via resistor R9. The source (S) is connected back to the negative feedback terminal of the integrated operational amplifier via resistor R10. The drain (D) is the analog current output terminal, which is connected to the detector.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (1) By setting up a current acquisition module, a voltage acquisition module and an A / D conversion module, and connecting the current acquisition module and the voltage acquisition module to the central processing unit through the A / D conversion module, the current and voltage of the detector are monitored in real time. The received real-time working current and real-time working voltage are then compared with the standard working current and standard working voltage stored in the central processing unit to diagnose the working status of the fixed detector.

[0014] (2) By setting up a temperature and humidity sensor, an alarm controller and an alarm, and connecting the temperature and humidity sensor and the alarm controller to the central processing unit and the alarm to the alarm controller, the concentration of natural gas or toxic gas under different temperature and humidity environments is monitored in real time. The real-time concentration information of combustible gas or toxic gas received is then compared with the standard gas concentration in the corresponding environment stored on the central processing unit to determine whether the current gas concentration exceeds the standard.

[0015] (3) By setting up a loop calibration module and connecting the loop calibration module to the central processing unit, the detector and the voltage acquisition module respectively, the pulse signal generated by the central processing unit modulates the reference voltage to generate a calibration signal, so as to perform online and real-time calibration of the output of the detector. Attached Figure Description

[0016] Figure 1 is a schematic diagram of the structure of the fixed detector online monitoring device of this utility model;

[0017] Figure 2 is a circuit diagram of the loop calibration module in the online monitoring device of the fixed detector of this utility model. Detailed Implementation

[0018] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described below are only for explaining the present invention and do not limit the scope of protection of the present invention.

[0019] The terms "first," "second," etc., used in the specification, claims, and embodiments of this application are used to distinguish similar objects, rather than to describe a specific order or sequence.

[0020] The present invention will be further described in detail below through preferred embodiments:

[0021] As shown in Figure 1, the fixed online monitoring device for detectors provided in this embodiment includes a current acquisition module, a voltage acquisition module, an A / D conversion module, a central processing unit (CPU), a temperature and humidity sensor, an alarm controller, and an alarm. The current and voltage acquisition modules are both connected to the CPU via the A / D conversion module. The temperature and humidity sensor and the alarm controller are both connected to the CPU, and the alarm is connected to the alarm controller. The detector is connected to the current acquisition module, the voltage acquisition module, and the CPU. Specifically, the input terminals of the current and voltage acquisition modules are connected to the detector, and their output terminals are connected to the CPU via the A / D conversion module. The output terminal of the temperature and humidity sensor is connected to the CPU, and the output terminal of the CPU is connected to the alarm controller.

[0022] The system comprises the following modules: a current acquisition module for acquiring the real-time operating current of the detector; a voltage acquisition module for acquiring the real-time operating voltage of the detector; an A / D conversion module for converting the acquired real-time operating current and voltage into digital signals and transmitting them to the central processing unit (CPU); a temperature and humidity sensor for acquiring the real-time temperature and humidity of the environment surrounding the detector and transmitting these signals to the CPU; an alarm controller for receiving alarm control signals from the CPU and controlling the alarm to sound; and an alarm for issuing corresponding alarm information based on the control of the alarm controller. The current acquisition module, voltage acquisition module, and A / D conversion module employ conventional configurations disclosed in the art. The current acquisition module can use current acquisition chips such as ACS712, ACS714, and INA282; the voltage acquisition module can use voltage acquisition chips such as AD7606 and SC1464; and the A / D conversion module can use A / D converters such as AD7875KNZ, ADS1000A0IDBVR, ADE9103, ADE9112, and ADE9113. The central processing unit can be an ADuCM361 controller. The temperature and humidity sensor is an SHT31. The alarm can be an audible and visual alarm, such as the GST-HX-M8501. The alarm controller can be implemented using a G6K-2F-Y relay.

[0023] It should be noted that the detector is only used to detect the concentration of combustible and toxic gases during the natural gas production process. After the concentration is detected, the determination of whether the concentration exceeds the standard needs to be made by the online monitoring device of the detector.

[0024] Specifically, the central processing unit first stores standard gas concentrations corresponding to different ambient temperature and humidity conditions. For example, when the temperature is <25℃ and the humidity is >50%, the alarm concentration threshold for toxic gases is set to 15ppm and the alarm concentration threshold for combustible gases is set to 50% LEL; when the temperature is 25℃~30℃ (excluding 30℃) and the humidity is 50%~45% (excluding 45%), the alarm concentration threshold for toxic gases is set to 10ppm and the alarm concentration threshold for combustible gases is set to 35% LEL; and when the temperature is ≥30℃ (maximum temperature) and the humidity is ≤45%, the alarm concentration threshold for toxic gases is set to 5ppm and the alarm concentration threshold for combustible gases is set to 25% LEL. These three sets of standard gas concentration ranges are used, where 5ppm is the concentration threshold for toxic gases corresponding to the highest temperature range (30℃) and 25% LEL is the concentration threshold for combustible gases corresponding to the temperature range ≥30℃. When either concentration exceeds the set threshold, an alarm is triggered. When the detector enters the working environment to be tested, the temperature and humidity sensor converts the temperature and humidity around the detector into analog signals and transmits them to the central processing unit (CPU). After receiving the analog signals, the CPU automatically matches the standard gas concentration range values ​​for that environment, i.e., what range of combustible gas and toxic gas concentrations is safe in the current environment. At the same time, the detector feeds back the concentration of the detected combustible or toxic gas to the CPU. The CPU compares the concentration range values ​​of the combustible or toxic gas fed back by the detector with the standard gas concentration range values ​​for that environment. If the concentration exceeds the standard gas concentration, for example, when the ambient temperature is 20℃, the humidity is 55%, and the detected toxic gas concentration is 20ppm, or the detected combustible gas concentration is 60% LEL, the CPU sends a control signal to the alarm controller to activate the alarm.

[0025] When monitoring the working status of the fixed detector, the online monitoring device first stores the standard working current and standard working voltage of the detector in the central processing unit. Then, the central processing unit compares the received real-time working current and real-time working voltage of the detector with the standard working current and standard working voltage respectively. If they exceed the standard working current and / or standard working voltage, the detector is judged to be in an abnormal working state.

[0026] To enable remote monitoring, this fixed detector online monitoring device also includes a remote transmission module. This module transmits the real-time concentrations of combustible and toxic gases detected by the detector, as well as any abnormal operating information of the detector, to a host computer (e.g., a PC). The remote transmission module can utilize an SP485 chip.

[0027] Example 2

[0028] This embodiment is a further improvement based on Embodiment 1.

[0029] To achieve real-time, online calibration of the fixed detector, the online monitoring device for the fixed detector provided in this embodiment also includes a loop calibration module. The loop calibration module is connected to the central processing unit, the detector, and the voltage acquisition module. The loop calibration module is used to calibrate the output of the detector. As shown in Figure 2, the loop calibration module includes an isolation submodule, a reference voltage submodule, a multi-stage filtering submodule, and a voltage-to-current conversion submodule. The input terminal of the isolation submodule is connected to the central processing unit, the output terminal of the isolation submodule is connected to the input terminal of the reference voltage submodule, the output terminal of the reference voltage submodule is connected to the input terminal of the multi-stage filtering submodule, the output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-to-current conversion submodule, and the output terminal of the voltage-to-current conversion submodule is connected to the detector.

[0030] The isolation submodule isolates digital and analog signals to prevent interference. A pulse signal generated by the central processing unit (CPU) is input to the isolation submodule. The output of the isolation submodule is connected to the input of a reference voltage submodule, which generates a reference voltage. A multi-stage filtering submodule selectively filters the modulated voltage output from the reference voltage submodule, reducing high-frequency noise and interference to improve signal transmission quality. A voltage-to-current conversion submodule converts the voltage to current and outputs a standard analog current signal. Furthermore, the isolation submodule includes a first chip U1, which is a voltage regulator chip HT7533. The reference voltage submodule includes a second chip U2, which is a TS5A31590. The pulse signal PWM1' generated by the central processing unit is connected to the input pin 7 of U1 via resistor R1 (5.1KΩ). The output pin 2 of U1 is connected to the input pin 6 of U2 via resistor R2 (5.1kΩ). The output pin 4 of U2 is connected to the input terminal of the multi-stage filtering submodule after being divided by resistors R3 (100kΩ) and R4 (100kΩ). The output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-current conversion submodule. The output terminal of the voltage-current conversion submodule is connected to the detector.

[0031] To effectively remove noise from the signal and improve signal quality and system stability, the multi-stage filtering submodule consists of a four-stage RC circuit, as shown in Figure 2. This includes capacitor C1 and resistor R5 (20kΩ), capacitor C2 and resistor R6 (20kΩ), capacitor C3 and resistor R7 (20kΩ), and capacitor C4 and resistor R8 (7.5kΩ). Here, capacitors C1, C2, C3, and C4 are all C104 capacitors.

[0032] Furthermore, the voltage-to-current conversion submodule includes an integrated operational amplifier and a MOSFET. The integrated operational amplifier functions as a voltage divider and controls the output voltage of the output modulation module. The MOSFET includes a gate (G), a source (S), and a drain (D). The output terminal 1 of the integrated operational amplifier is connected to the gate (G) of the MOSFET via resistor R9 (3.3kΩ). The source (S) of the MOSFET is connected back to the negative feedback terminal of the integrated operational amplifier via resistor R10 (7.5kΩ) and grounded via resistor R11 (10kΩ). The drain (D) of the MOSFET is the analog current output terminal, which is connected to the detector. The integrated operational amplifier is an LM258; the MOSFET is an NTF3055.

[0033] The specific working principle of the loop calibration module for calibrating the output of the detector is as follows: The central processing unit generates a corresponding pulse signal PWM1' based on the value that the detector needs to calibrate. This pulse signal PWM1' is connected to pin 7 of the isolation submodule U1 via resistor R1. The output of pin 2 of the isolation submodule U1 is connected to pin 6 of the reference voltage submodule U2 via resistor R2. The modulated voltage output from the reference voltage submodule U73 is divided by resistors R3 and R4, and then filtered by a four-electrode filter circuit consisting of capacitors C1, R5, C2, R6, C3, R7, C4, and R8 to obtain a 0.2-1V standard analog voltage signal, which is then sent to the input of the voltage-to-current conversion submodule. Finally, the voltage-to-current conversion submodule outputs a 4-20mA standard analog signal to calibrate the detector loop. The central processing unit reads the value of the detector on the loop and compares it with the generated standard analog signal to determine whether it is within the given error range. If it is within the error range, the accuracy of the loop meets the requirements; otherwise, the accuracy of the loop is low, and the loop needs to be adjusted.

[0034] The preferred embodiments of this application have been described in detail above with reference to the accompanying drawings. Typical known structures and common knowledge techniques in the preferred embodiments have not been described in detail here. Those skilled in the art can improve and implement the technical solution of this utility model based on the inspiration given in these embodiments and their own capabilities. Some typical known structures, known methods or common knowledge techniques should not be obstacles for those skilled in the art to implement this application.

[0035] The scope of protection claimed in this application shall be determined by the contents of its claims. The contents of the utility model description, specific embodiments, and drawings are used to interpret the claims.

[0036] Within the scope of the technical concept of this application, several modifications can be made to the specific implementation of this application, and these modified implementations should also be considered within the protection scope of this application.

Claims

1. A fixed-type online monitoring device, characterized in that: It includes a current acquisition module, a voltage acquisition module, an A / D conversion module, a central processing unit, a temperature and humidity sensor, an alarm controller, and an alarm. The current acquisition module and the voltage acquisition module are both connected to the central processing unit through the A / D conversion module. The temperature and humidity sensor and the alarm controller are both connected to the central processing unit. The alarm is connected to the alarm controller. The detector is connected to the current acquisition module, the voltage acquisition module, and the central processing unit respectively.

2. The fixed detector online monitoring device according to claim 1, characterized in that: It also includes a remote transmission module, which is connected to the central processing unit.

3. The fixed detector online monitoring device according to claim 2, characterized in that: It also includes a loop calibration module, which is connected to the central processing unit, the detector and the voltage acquisition module respectively. The loop calibration module is used to calibrate the output of the detector.

4. The fixed detector online monitoring device according to claim 3, characterized in that: The loop calibration module includes an isolation submodule, a reference voltage submodule, a multi-stage filtering submodule, and a voltage-to-current conversion submodule. The input terminal of the isolation submodule is connected to the central processing unit, the output terminal of the isolation submodule is connected to the input terminal of the reference voltage submodule, the output terminal of the reference voltage submodule is connected to the input terminal of the multi-stage filtering submodule, the output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-to-current conversion submodule, and the output terminal of the voltage-to-current conversion submodule is connected to a detector.

5. The fixed detector online monitoring device according to claim 4, characterized in that: The isolation submodule includes a first chip U1, and the reference voltage submodule includes a second chip U2. The pulse signal generated by the central processing unit is connected to the input pin of U1 via resistor R1. The output pin of U1 is connected to the input pin of U2 via resistor R2. The output pin of U2 is connected to the input terminal of the multi-stage filtering submodule after being divided by resistors R3 and R4. The output terminal of the multi-stage filtering submodule is connected to the input terminal of the voltage-current conversion submodule. The output terminal of the voltage-current conversion submodule is connected to the detector.

6. The fixed detector online monitoring device according to claim 4 or 5, characterized in that: The multi-stage filtering submodule includes a four-stage filtering circuit consisting of capacitor C1 and resistor R5, capacitor C2 and resistor R6, capacitor C3 and resistor R7, and capacitor C4 and resistor R8.

7. The fixed detector online monitoring device according to claim 4 or 5, characterized in that: The voltage-to-current conversion submodule includes an integrated operational amplifier and a MOS field-effect transistor. The MOS field-effect transistor includes a gate (G), a source (S), and a drain (D). The output terminal of the integrated operational amplifier is connected to the gate (G) via resistor R9. The source (S) terminal is connected back to the negative feedback terminal of the integrated operational amplifier via resistor R10. The drain (D) terminal is the analog current output terminal, which is connected to the detector.

Images