A pressure switch sensor detection device and detection method

Abstract

The present invention discloses a detection device and a detection method for a pressure switch sensor. The detection device includes a control module, a pressure measurement module, a pressure switch sensor interface module, a power supply and battery management module, a display module, and a function key module. The control module is configured to receive data from the pressure measurement module, the pressure switch sensor interface module, and the function key module, and output the processed result to the display module. The pressure measurement module is used to obtain the pressure value of the pressure transmitter. The pressure switch sensor interface module is used to calibrate an external pressure switch sensor. The power supply and battery management module is used to supply power to the control module, the pressure measurement module, the pressure switch sensor interface module, and the display module. The function key module is used to input control commands. By setting the above modules, the present invention can automatically identify the action changes of the pressure switch sensor and realize the automatic calibration of the working state of the pressure switch sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure detection, and particularly relates to a pressure switch sensor detection device and a detection method. Background Art

[0002] In power systems and other electrical control systems, various types of pressure switch sensors (pressure switches) are often applied to occasions where pressure measurement is required, as locking action elements or starting elements for pressure protection. The working reliability of the pressure switch sensor is an important guarantee for ensuring the reliable operation of the pressure detection system and other pressure control systems. Therefore, it is necessary to regularly test the characteristic parameters of the pressure switch sensor to ensure the accuracy and correctness of its operation. The traditional maintenance methods of the pressure switch sensor mainly have the following two main problems:

[0003] First, since the pressure switch sensor has always been calibrated in a completely manual manner. Facing the regular inspection work of a pressure detection system containing a large number of pressure switch sensors, technicians need to perform a large amount of repetitive labor, resulting in a large labor intensity and low calibration efficiency of the technicians, and it is easy to cause fatigue.

[0004] Second, the subjectivity of whether the calibration data meets the technical requirements is relatively strong. At present, the pressure switch sensor is calibrated through a traditional pressure calibrator. During the calibration, one staff member operates the handle of the pressure application device to complete the specified pressure application operation, and another staff member connects a multimeter and a traditional pressure calibrator. While measuring the action condition of the switch-type pressure switch sensor, the pressure value displayed by the traditional pressure calibrator is also observed in real time. When the switch-type pressure switch sensor triggers the switch on / off during the pressure application process of the external pressure application device, the staff member immediately stops the pressure application and records the pressure value displayed by the current traditional pressure calibrator. This pressure value is the action threshold of the switch-type pressure switch sensor. For the operator of the pressure calibrator, the situation of excessive pressure application or excessive pressure relief often occurs. For the measurer of the sensor node, it is necessary to hold the multimeter by hand, observe the action condition of the multimeter with the naked eye, and manually record the action pressure result, which leads to a delay in the action of the pressure switch sensor and a certain subjectivity in the reading; moreover, using the manual method to record the measurement results is not conducive to the recording, storage, and analysis of data. Summary of the Invention

[0005] In view of the above problems, the present invention proposes a pressure switch sensor detection device, which mainly solves the problem that the traditional pressure measurement and the calibration of the pressure switch sensor are separated and the actual application is cumbersome.

[0006] To solve the above technical problems, on the one hand, the present invention provides a pressure switch sensor detection device, including a control module, a pressure measurement module, a pressure switch sensor interface module, a power supply and battery management module, a display module, and a function key module; the control module is used to receive data from the pressure measurement module, the pressure switch sensor interface module, and the function key module, and after processing, output the result to the display module; the pressure measurement module is used to obtain the pressure value of the pressure transmitter; the pressure switch sensor interface module is used to switch between the resistance range or voltage range according to the type of the external pressure switch sensor; the power supply and battery management module is used to supply power to the control module, the pressure measurement module, the pressure switch sensor interface module, and the display module; the function key module is used to input control commands.

[0007] On the other hand, the present invention provides a pressure switch sensor detection method, using the above pressure switch sensor detection device, including the following steps:

[0008] Step 1, initialization; Step 2, determine whether to perform calibration. If so, first perform the calibration process, and after the calibration process, perform power management. If not, directly perform power management; Step 3, perform pressure measurement to obtain the pressure value; Step 4, display the pressure value.

[0009] The beneficial effects of the present invention are as follows: By setting the control module, the pressure measurement module, the pressure switch sensor interface module, the power supply and battery management module, the display module, and the function key module, the detection device of the present invention can automatically identify the action changes of the pressure switch sensor and realize the automatic calibration of the working state of the pressure switch sensor. Description of the Drawings

[0010] Figure 1 It is a schematic diagram of the pressure switch sensor detection device disclosed in the embodiment of the present invention;

[0011] Figure 2 It is the minimum system of STM32F103RCT6 disclosed in the embodiment of the present invention;

[0012] Figure 3 It is a schematic diagram of the gear shift of the pressure switch sensor interface module disclosed in the embodiment of the present invention;

[0013] Figure 4 It is the switching circuit diagram of the pressure switch sensor interface module disclosed in the embodiment of the present invention;

[0014] Figure 5 It is a schematic block diagram of the resistance range measurement principle of the pressure switch sensor interface module disclosed in the embodiment of the present invention;

[0015] Figure 6The voltage division circuit diagram of the resistance range disclosed in the embodiments of the present invention;

[0016] Figure 7 The constant current source circuit diagram of the pressure switch sensor interface module disclosed in the embodiments of the present invention;

[0017] Figure 8 The principle block diagram of the voltage range measurement of the pressure switch sensor interface module disclosed in the embodiments of the present invention;

[0018] Figure 9 The three-way voltage measurement switching circuit diagram disclosed in the embodiments of the present invention;

[0019] Figure 10 The overvoltage and overcurrent protection circuit diagram of the voltage range disclosed in the embodiments of the present invention;

[0020] Figure 11 The application circuit diagram of the isolation amplifier disclosed in the embodiments of the present invention;

[0021] Figure 12 The application circuit diagram of the DC-DC isolation power supply disclosed in the embodiments of the present invention;

[0022] Figure 13 The principle block diagram of the pressure measurement module disclosed in the embodiments of the present invention;

[0023] Figure 14 The application circuit diagram of the 24V boost unit disclosed in the embodiments of the present invention;

[0024] Figure 15 The typical application circuit of ADR423 disclosed in the embodiments of the present invention;

[0025] Figure 16 The application circuit diagram of the pressure measurement module disclosed in the embodiments of the present invention;

[0026] Figure 17 The system block diagram of the power supply and battery management module disclosed in the embodiments of the present invention;

[0027] Figure 18 The circuit diagram of the power supply switching module disclosed in the embodiments of the present invention;

[0028] Figure 19 The circuit diagram of the battery charging management unit and the battery boost unit disclosed in the embodiments of the present invention;

[0029] Figure 20 The circuit diagram of the battery charging protection unit and the battery discharge protection unit disclosed in the embodiments of the present invention;

[0030] Figure 21 The main program flow chart of the pressure switch sensor detection method disclosed in the embodiments of the present invention;

[0031] Figure 22 Flow chart of the inspection process disclosed in the embodiments of the present invention;

[0032] Wherein: 1 - control module, 2 - pressure measurement module, 3 - pressure switch sensor interface module, 4 - power supply and battery management module, 5 - display module, 6 - function key module. Detailed implementation manners

[0033] To make the objectives, technical solutions and advantages of the present invention clearer and more definite, the content of the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of convenience of description, only parts related to the present invention are shown in the accompanying drawings rather than all the content.

[0034] One application object of the present invention is Guangzhou Pumped Storage Power Plant. The main models of the detection object (pressure switch sensor) are PressswZPN206SH, 5 - 50 bar, Pressureswitch200 - 1750 PSI, RPPN CA3207, etc. On this basis, the present invention can achieve pressure measurement within 200 bar and automatic detection of various types of pressure switch sensors.

[0035] As Figure 1 shown, this embodiment provides a pressure switch sensor detection device, including a control module 1, a pressure measurement module 2, a pressure switch sensor interface module 3, a power supply and battery management module 4, a display module 5, and a function key module 6; the control module 1 is used to receive data from the pressure measurement module 2, the pressure switch sensor interface module 3, and the function key module 6, and after processing, output the result to the display module 5; the pressure measurement module 2 is used to obtain the pressure value of the pressure transmitter; the pressure switch sensor interface module 3 is used to switch between the resistance range or voltage range according to the type of the external pressure switch sensor; the power supply and battery management module 4 is used to supply power to the control module 1, the pressure measurement module 2, the pressure switch sensor interface module 3, and the display module 5; the function key module 6 is used to input control commands.

[0036] The detection device of the present invention realizes the automatic verification of the working state of the pressure switch sensor by setting the control module 1, the pressure measurement module 2, the pressure switch sensor interface module 3, the power supply and battery management module 4, the display module 5, and the function key module 6, and automatically identifies the action changes of the pressure switch sensor. Using the above device is more convenient than the pressure calibration instrument measurement technology that requires an additional multimeter.

[0037] Furthermore, the control module 1 is STM32F103RCT6, and its minimum system is asFigure 2 As shown. The display module 5 uses a 3.12-inch blue OLED screen with a resolution of 256x64. The screen interface is an SPI serial bus interface. Its main function is to display the pressure measurement value, the status of the pressure switch sensor, and the system status. The system status includes the current status of the power supply and the battery management module 4, the gear position of the current pressure switch sensor interface, the operation indication, and the temperature of the control module 1.

[0038] The function key module 6 includes 5 tactile switches, which are respectively used to implement specific functions. The same key realizes different functions according to different menus, such as the run / hold function, the trigger start / trigger stop function, the pressure value zeroing function, the pressure unit switching, and the key lock function. The run / hold function is applicable to the pressure measurement module. Each time the key is pressed, the pressure measurement switches between the running and holding states. The pressure value zeroing function is applicable to the pressure measurement module and is used to compensate for the external pressure zero point. The pressure unit switching is applicable to the pressure measurement module and the pressure switch sensor interface module and is used to switch between the commonly used pressure display units bar, psi, and MPa. The key lock function is applicable to the pressure measurement module and the pressure switch sensor interface module. When the lock key is long-pressed for 5 s, the operation of the other 4 keys is locked or unlocked. It also includes a sounding module, which is a buzzer. The trigger start / trigger stop function is only applicable to the pressure switch sensor interface module. When this function starts, the calibrator monitors the interface status of the pressure switch sensor. When the status changes, the display of the current pressure value is locked, and the change of the interface status is indicated. At the same time, the buzzer emits a loud prompt.

[0039] As Figure 3 shown, the pressure switch sensor interface module 3 is converted to a resistance gear or a voltage gear by setting a mechanical contact switch. The resistance gear and the voltage gear respectively correspond to the switch-type pressure switch sensor and the voltage-type pressure switch sensor. Under normal circumstances, when the pressure switch sensor detects that the pressure exceeds a certain threshold, it will perform a mechanical action or an electrical action. The switching circuits of different types of pressure switch sensors are as Figure 4 shown, where the core is the mechanical relay G6S-2-5VDC. The mechanical action is manifested as the change of the contact switch, that is, the normally open contact will become the normally closed contact, or the normally closed contact will become the normally open contact. This is called the switch-type pressure switch sensor; the electrical action is normally charged, and when it acts, the interface voltage changes by more than 10V. This is called the voltage-type pressure switch sensor. The inputs of the pressure switch sensor interface module 3 include the R port, the G port, the B port, and the COM port. The four ports of the R port, the G port, the B port, and the COM port correspond to the voltage gear, and the three ports of the R port, the G port, and the B port correspond to the resistance gear.

[0040] As Figure 5As shown, one of the ports of the resistor range outputs the constant current source generated by the constant current source generator to the switch type pressure switch sensor, and the other two ports of the resistor range respectively obtain the voltage of the switch type pressure switch sensor, and input it to the analog-to-digital converter after passing through the sampling resistor. Figure 6 As shown, the maximum measurement voltage is 400V, and a high impedance input terminal of about 1.66MΩ is formed by connecting 332KΩ in series with a multi-level 1206 package and a withstand voltage of 200V. The voltage division output adopts 1nF filtering, and a 15V bidirectional TVS tube is used to protect the voltage division output. The circuit structure of the constant current source generator is shown in Figure 7 As shown. For the switch type pressure switch sensor, the pressure switch sensor interface module 3 outputs a constant current source. According to Ohm's law, the sampling resistor voltage can be measured to obtain the resistance value of the external pressure switch interface. This value is used to judge the short circuit / open circuit of the internal switch of the pressure switch sensor. The principle is similar to the short circuit function of the multimeter. This measurement is only used as an on-off judgment and cannot accurately measure the pressure value. The result is only a switch value.

[0041] like Figure 8 As shown, the voltage range includes three ports for accessing voltage, the output end of the port is connected to the input end of the overvoltage and overcurrent protection circuit, the output end of the overcurrent protection circuit is connected to the input end of the voltage divider resistor, the output end of the voltage divider resistor is connected to the input end of the isolation amplifier, and the output end of the isolation amplifier is connected to the input end of the analog-to-digital converter. The interface voltage measurement circuit of the voltage range is as follows Figure 9 As shown in FIG. 1 , PhotoMOS optical coupler AQW210 is used as a switching switch to measure the voltage of three interfaces in a time-sharing manner; the overcurrent protection circuit of the voltage measurement is shown in FIG. Figure 10 As shown in the figure, the core is a fast-blow fuse and a varistor 7D431K, with a protection current of 0.25A, a protection voltage range of 387 to 473V, a continuous use voltage range of 275 to 350V, and a maximum limit of 710V. The circuit of the isolation amplifier is shown in the figure. Figure 11 As shown, the core is the high-precision isolation amplifier AMC1200, with a silicon dioxide (SiO2) barrier with high magnetic field immunity isolating the output from the input. According to UL1577 and IEC60747-5-2 standards, the isolation barrier is certified to provide voltage isolation up to 4000V peak. It also includes a DC-DC isolated power supply, such as Figure 12 As shown, the integrated DC-DC isolation power module B0505LS-2WR2 is used as the core to power the isolation amplifier.

[0042] like Figure 13As shown in the figure, the pressure measurement module 2 includes a pressure transmitter, a sampling resistor, an analog-to-digital converter, a 24V boost unit, and a voltage reference source unit. The pressure transmitter is used to linearly convert the pressure value (external pressure) received by the pressure switch sensor into a 4-20mA current output value. The sampling resistor is used to convert the current output value into a voltage output value. The analog-to-digital converter reads the voltage output value and converts it into a corresponding pressure value. The 24V boost unit is used to boost the 5V voltage output by the power supply and battery management module 4 to 24V to power the pressure transmitter. The voltage reference source unit generates a 3V reference voltage with a temperature drift of 3ppm / ℃, which is used as the reference voltage for the analog-to-digital converter and the constant current source generator. The pressure range of the pressure transmitter is 20MPa, it is powered by 24V DC, and the accuracy is ±0.2%. The voltage reference source unit is the ultra-precision, second-generation externally implanted ion field effect transistor (XFET) reference voltage source ADR423 of ADI Company. The 24V boost unit of the pressure switch sensor is as Figure 14 shown, and the core is the SX1308 switching power supply boost chip. The voltage reference source unit is as Figure 15 shown, the core is ADR423, which generates a 3V reference voltage with a temperature drift of 3ppm / ℃, and is used as the reference voltage for the ADC and the constant current source generator. The circuit of the pressure measurement module 2 is as Figure 16 shown, the core chip is a 24-bit analog-to-digital converter ADS1220, and the sampling resistor is a thin film resistor with an accuracy of 100R 0.05% from Viking Company, and the temperature drift coefficient is only ±5ppm / ℃, meeting the system requirements.

[0043] As Figure 17 shown, the power supply and battery management module 4 includes a power adapter, a redundant power supply module, and a power switching module. The output end of the power adapter is connected to the input ends of the redundant power supply module and the power switching module. The output end of the redundant power supply module is connected to the input end of the power switching module. The power switching module is used to switch to the power supply of the power adapter or the redundant power supply module. The redundant power supply module includes a dual-channel battery module, and any one of the battery modules includes a battery charging management unit, a battery charging protection unit, a battery, a battery discharge protection unit, and a battery boost unit arranged in sequence.

[0044] The circuit diagram of the power switching module is as Figure 18 shown, and the core switching components are two P-channel MOS transistors APM4953. The external adapter voltage is 5V, which can realize the automatic switching between the power adapter and the redundant power supply module. The batteries are two 18650 lithium-ion batteries with a capacity of 3200mAH. The two batteries are designed to work redundantly and have independent battery charging management units and battery charging protection units. Even if one of the batteries fails, it will not affect the normal operation of the calibrator, only the battery life will be reduced, and there is no consistency requirement for the two batteries, which is convenient for subsequent maintenance.

[0045] The circuits of the battery charging management unit and the battery boost unit are as follows Figure 19 shown. The core part is TP5400. This chip integrates a charging management circuit and a 5V boost circuit. The typical charging current is 1A, and the typical boost output current is 1A.

[0046] The circuits of the battery charging protection unit and the battery discharging protection unit are as follows Figure 20 shown. The core is composed of the dedicated protection chip DW01A for single-cell lithium-ion batteries and the dual N-channel MOS transistor FS8205A.

[0047] As Figure 21 、 22 shown, a method for detecting a pressure switch sensor uses the above-mentioned pressure switch sensor detection device and includes the following steps

[0048] Step 1, initialization; Step 2, determine whether to perform calibration. If so, first perform calibration processing, and then perform power management after the calibration processing. If not, directly perform power management. Step 3, perform pressure measurement to obtain the pressure value. Step 4, display the pressure value.

[0049] The calibration processing includes the following steps. Step 2.1, determine whether the port of the pressure switch sensor interface module 3 is energized;

[0050] Step 2.11, if not energized, switch to the resistance range, memorize the current state of the pressure switch sensor. Step 2.12, determine whether the state of the pressure switch sensor changes within a specified time. Step 2.13, if it changes, immediately collect the pressure value of the pressure switch sensor, lock the pressure value, display the pressure value on the display module 5, and emit a prompt sound. If it does not change, return to Step 2.11;

[0051] Step 2.21, if energized, switch to the voltage range, memorize the current state of the pressure switch sensor. Step 2.22, determine whether the state of the pressure switch sensor changes within a specified time. Step 2.23, if it changes, immediately collect the pressure value of the pressure switch sensor, lock the pressure value, display the pressure value on the display module 5, and emit a prompt sound. If it does not change, return to Step 2.21.

[0052] The above embodiments are only used to illustrate the technical concept and features of the present invention. The purpose is to enable ordinary technicians in the field to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the essence of the content of the present invention should be covered within the protection scope of the present invention.

Claims

1. A pressure switch sensor detection device, characterized in that, it includes a control module, a pressure measurement module, a pressure switch sensor interface module, a power supply and battery management module, a display module and a function key module; the control module is used to receive data from the pressure measurement module, the pressure switch sensor interface module and the function key module, and after processing, output the result to the display module; the pressure measurement module is used to obtain the pressure value of the pressure transmitter; the pressure switch sensor interface module is used to switch between the resistance range or the voltage range according to the type of the external pressure switch sensor; the power supply and battery management module is used to supply power to the control module, the pressure measurement module, the pressure switch sensor interface module and the display module; the function key module is used to input control commands; The pressure switch sensor interface module is converted into a resistance range or a voltage range by setting a mechanical contact switch, and the resistance range and the voltage range respectively correspond to a switch-type pressure switch sensor and a voltage-type pressure switch sensor; One of the ports of the resistance range outputs the constant current source generated by the constant current source generator to the switch-type pressure switch sensor, and the other two ports of the resistance range respectively obtain the voltage of the switch-type pressure switch sensor, and after passing through the sampling resistor, input it to the analog-to-digital converter; The voltage range includes three ports for accessing voltage, the output end of the port is connected to the input end of the overvoltage and overcurrent protection circuit, the output end of the overcurrent protection circuit is connected to the input end of the voltage dividing resistor, the output end of the voltage dividing resistor is connected to the input end of the isolation amplifier, and the output end of the isolation amplifier is connected to the input end of the analog-to-digital converter.

2. The pressure switch sensor detection device according to claim 1, characterized in that, the pressure measurement module includes a pressure transmitter, a sampling resistor, an analog-to-digital converter, a 24V boost unit and a voltage reference source unit, the pressure transmitter is used to linearly convert the pressure value received by the pressure switch sensor into a 4~20mA current output value, the sampling resistor is used to convert the current output value into a voltage output value, the analog-to-digital converter reads the voltage output value and converts it into the corresponding pressure value, the 24V boost unit is used to boost the 5V voltage output by the power supply and battery management module to 24V to supply power to the pressure transmitter; the voltage reference source unit generates a 3V reference voltage with a temperature drift of 3ppm / ℃, which is used as the reference voltage for the analog-to-digital converter and the constant current source generator.

3. The pressure switch sensor detection device according to claim 1 or 2, characterized in that, the analog-to-digital converter is ADS1220.

4. The pressure switch sensor detection device according to claim 1, characterized in that, the power supply and battery management module includes a power adapter, a redundant power supply module and a power switch module, the output end of the power adapter is connected to the input ends of the redundant power supply module and the power switch module, the output end of the redundant power supply module is connected to the input end of the power switch module, and the power switch module is used to switch to the power supply of the power adapter or the redundant power supply module.

5. The pressure switch sensor detection device according to claim 4, characterized in that, the redundant power supply module includes a dual-channel battery module, and any one of the battery modules includes a battery charging management unit, a battery charging protection unit, a battery, a battery discharging protection unit, and a battery boosting unit arranged in sequence.

6. A pressure switch sensor detection method, characterized in that, using the pressure switch sensor detection device according to claim 5, comprising the following steps, Step 1, initialization, Step 2, determine whether to perform calibration. If so, first perform calibration processing, and after the calibration processing, perform power management. If not, directly perform power management. Step 3, perform pressure measurement to obtain the pressure value. Step 4, display the pressure value.

7. The pressure switch sensor detection method according to claim 6, characterized in that, the calibration processing includes the following steps, Step 2.1, determine whether the port of the pressure switch sensor interface module is energized; Step 2.11, if not energized, switch to the resistance range, memorize the current state of the pressure switch sensor. Step 2.12, determine whether the state of the pressure switch sensor has changed within a specified time. Step 2.13, if it has changed, immediately collect the pressure value of the pressure switch sensor, lock the pressure value, display the pressure value on the display module, and emit a prompt sound. If it has not changed, return to Step 2.11; Step 2.21, if energized, switch to the voltage range, memorize the current state of the pressure switch sensor. Step 2.22, determine whether the state of the pressure switch sensor has changed within a specified time. Step 2.23, if it has changed, immediately collect the pressure value of the pressure switch sensor, lock the pressure value, display the pressure value on the display module, and emit a prompt sound. If it has not changed, return to Step 2.21.

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