Metering pump frequency control system

Abstract

The utility model provides a metering pump frequency control system which comprises an STM32F103RCT6 single-chip microcomputer, a flow monitoring module, a metering pump control module, a sensor detection module, a display module and a power supply module. The STM32F103RCT6 single chip microcomputer is connected with the flow monitoring module, the metering pump control module and the sensor detection module respectively. According to the utility model, through the flow monitoring module, the set target concentration information and the combination of the sensor detection module, the precise control of the liquid concentration is realized, and the problems of insufficient control precision and incapability of timely response and adjustment in the prior art are solved.

Description

Technical Field

[0001] The utility model belongs to the field of industrial process control and fluid regulation technology, and specifically relates to a metering pump frequency control system. By integrating flow metering, sensor dynamic monitoring and closed-loop regulation technology, accurate control of target liquid concentration in the industrial fluid processing process is achieved. Background Art

[0002] In the field of liquid processing and delivery, metering pumps are widely used in chemical injection, water treatment, agricultural irrigation and other scenarios. Their main function is to accurately control the delivery volume and concentration of liquids. Traditional metering pump control methods usually rely on fixed flow or fixed set frequency control methods, and cannot automatically adjust the output frequency of the pump according to real-time flow and concentration changes, resulting in insufficient control accuracy. Especially in the case of flow fluctuations or changes in liquid concentration, traditional methods cannot respond and adjust in time, affecting the effect and efficiency of liquid treatment. Therefore, there is an urgent need for a new technology that can efficiently and accurately adjust the operating frequency of the metering pump to achieve precise liquid concentration control. Summary of the invention

[0003] In order to solve the technical problems mentioned in the above background technology, a metering pump frequency control system is proposed. The utility model sets the target concentration of liquid by pressing a button, combines the flow meter to monitor the liquid flow rate and the pH value and ORP value detected by the sensor, dynamically adjusts the working frequency of the metering pump according to the feedback algorithm of the control system, and displays the relevant data on the OLED display screen to achieve precise control of the liquid concentration.

[0004] The technical means adopted by the utility model are as follows:

[0005] Metering pump frequency control system, including:

[0006] STM32F103RCT6 microcontroller, flow monitoring module, metering pump control module, sensor detection module, display module and power module;

[0007] The output end of the flow monitoring module is connected to the input end of the STM32F103RCT6 single chip microcomputer to obtain the water flow information entering the system;

[0008] The input end of the metering pump control module is connected to the output end of the STM32F103RCT6 single chip microcomputer, and is used to control the working frequency of the metering pump and adjust the delivery amount of the stock liquid;

[0009] The output end of the sensor detection module is connected to the input end of the STM32F103RCT6 single-chip microcomputer, and is used to feed back the detected pH value and ORP value to the single-chip microcomputer;

[0010] The output end of the power module is connected to the STM32F103RCT6 single chip microcomputer, the flow monitoring module, the metering pump control module, and the sensor detection module, and is used to provide power supply voltage to each module.

[0011] Furthermore, the output signal of the flow monitoring module is connected to the PA10 pin of the GPIO port of the STM32F103RCT6 chip through a current limiting resistor R7, one end of the pull-up resistor R6 is connected to the +12V voltage, and the other end is connected to the output pin of the flow monitoring module, which is used to clamp the uncertain signal to a high level. At the same time, the filter capacitor C12 is connected in parallel with the electrostatic protection diode D1, one end is connected to the signal output, and the other end is grounded, which is used to eliminate high-frequency noise and surge voltage interference in the signal.

[0012] Furthermore, the PA11 interface of the STM32F103RCT6 single-chip microcomputer outputs a pulse signal, which is connected to the 2nd pin of the optocoupler through the current limiting resistor R9, the 1st pin of the optocoupler is connected to VCC, the 3rd pin is grounded, and the frequency signal is output from the 4th pin, and is input into the metering pump control module after passing through the current limiting resistor R11. The filter capacitor C13, the pull-down resistors R8 and R10 are connected in parallel, one end is connected to the 4th pin of the optocoupler, and the other end is grounded. The anode of the voltage stabilizing diode D2 is grounded, and the cathode is connected to the 4th pin of the optocoupler to protect the light-emitting diode of the optocoupler from electrostatic interference.

[0013] Furthermore, the sensor detection circuit detects signals through the pH sensor and the ORP sensor, respectively amplifies the signals through the operational amplifiers U3.1 and U4.1, and the output signals are connected to the ADS1115 chip, and after chip conversion, are output to the GPIO interfaces PB10 and PB11 of the single-chip computer through the IIC. Capacitors C14-C21 are connected between the positive and negative voltages and the analog ground to play a power supply filtering role. Resistors R13 and R14 are connected in series, and resistors R18 and R19 are connected in series, which are used to control the amplification factors of the operational amplifiers U3.1 and U4.1, respectively.

[0014] Furthermore, the power module connects the +12V voltage to the 5-pin of the chip U6 through the fuse F1, and the 3-pin of the chip U6 outputs the +5V voltage after the inductor L1 continues the current, and the capacitors C23, C24, C26, and C27 play the role of power supply filtering. The voltage regulator diode D3 is connected to the 3-pin of the chip U6 and PGND for voltage stabilization. The chip U7 inputs the +5V voltage and outputs the +3.3V voltage. The chip U8 is used to convert the +5V input voltage to a negative voltage of -5V. The resistance values ​​of the resistors R24 and R25 are both 0Ω, which are connected between two different ground pins to reduce the interference of the digital ground to the analog ground.

[0015] Compared with the prior art, the utility model has the following advantages:

[0016] The utility model combines the flow monitoring module with the information of the set target concentration, and adjusts the metering pump frequency through real-time calculation, thereby solving the problem of the traditional method not responding in time under the condition of flow fluctuation and concentration change.

[0017] The utility model feeds back the concentration data detected by the pH and ORP sensors to the control system, and the system quickly adjusts the frequency of the metering pump through a feedback regulation algorithm based on the feedback information, thereby solving the problems of long system response time and low adjustment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 This is a schematic diagram of the overall block diagram of the frequency control system of the utility model metering pump;

[0020] Figure 2 This is a schematic diagram of the flow monitoring module of the utility model;

[0021] Figure 3 This is a schematic diagram of the control module of the metering pump of the utility model;

[0022] Figure 4 It is a schematic diagram of the sensor detection module of the utility model;

[0023] Figure 5 It is a schematic diagram of the power module of the utility model. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0026] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0027] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the utility model. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once a certain item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0028] In the description of the present utility model, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present utility model and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present utility model: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0029] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0030] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0031] like Figure 1-5 The metering pump frequency control system shown in the figure includes: STM32F103RCT6 single chip microcomputer, flow monitoring module, metering pump control module, sensor detection module, display module and power module. The target concentration of the liquid is set by pressing buttons, and the metering pump control module is controlled to work in combination with the flow information of the flow monitoring module. At the same time, relying on the pH value and ORP value detected by the sensor, the control system uses a feedback algorithm to dynamically adjust the working frequency of the metering pump, and displays the relevant data on the OLED display to achieve precise control of the liquid concentration.

[0032] The output end of the flow monitoring module is connected to the input end of the STM32F103RCT6 microcontroller, and is continuously monitored when the system is working. It is used to obtain the water flow information entering the system and display it on the display module. By comparing it with the set target concentration, the required working frequency of the metering pump control module is calculated;

[0033] The input end of the metering pump control module is connected to the input end of the STM32F103RCT6 microcontroller through an optical coupler to receive the frequency signal sent by the main control chip, so as to work at a given frequency;

[0034] The output end of the sensor detection module is connected to the input end of the STM32F103RCT6 microcontroller to measure the pH value and ORP value of the liquid after mixing; when the detected value is inconsistent with the target concentration, the STM32F103RCT6 microcontroller will use a feedback algorithm to dynamically adjust the operating frequency of the metering pump control module to accurately control the liquid output at the specified concentration.

[0035] The output end of the power module is connected to the input end of the STM32F103RCT6 single chip microcomputer, the flow monitoring module, the metering pump control module, and the sensor detection module to provide the required working voltage for each module.

[0036] As a preferred embodiment, in the present application, the output signal of the flow detection module is connected to the PA10 pin of the STM32F103RCT6 single-chip microcomputer via a current limiting resistor R7, and one end of the ESD diode D1 is connected to the output signal, and the other end is grounded to suppress static electricity or surge interference that may occur on the signal line. At the same time, the filter capacitor C12 is connected in parallel with the diode D1 to eliminate high-frequency noise interference in the signal. The pull-up resistor R6 is connected to the signal line at one end and the +12V voltage at the other end to clamp the output signal at a high level when uncertain, maintaining it in an untriggered state or returning to the original state after being triggered.

[0037] As a preferred embodiment, in the present application, the metering pump control module is connected to the STM32F103RCT6 single-chip microcomputer through an optical coupler to prevent the large current of the metering pump from affecting the normal operation of the MCU. The current limiting resistor R11 is connected between the 4 pins of the optical coupler and the signal pin of the metering pump to prevent the light-emitting diode of the optical coupler from being burned. One end of the filter capacitor C13 is connected to the signal line and the other end is grounded. Pull-down resistors R8 and R10 are connected in parallel with capacitor C13 to prevent the optical coupler pin from floating when there is no signal. The cathode of the voltage-stabilizing diode D2 is connected to the signal line, and the anode is grounded to protect the light-emitting diode of the optical coupler from electrostatic interference. The signal converted by the optical coupler is connected to the STM32F103RCT6 single-chip microcomputer PA11 pin through the current limiting resistor R9.

[0038] As a preferred embodiment, in the present application, the RF1 of the sensor detection module is a pH and ORP sensor interface, and the pH and ORP signals are output through pins 1 and 2 respectively, and are connected to pins 3 of operational amplifiers U3.1 and U4.1 through resistors R12 and R16. Capacitors C14-C21 are power filter capacitors, one end is connected to ±5V, and the other end is connected to AGND. Resistors R13 and R14 are connected in series, one end is connected to pin 1 of the operational amplifier, and the other end is connected to AGND, which is used to control the amplification factor of the operational amplifier, and resistors R18 and R19 are the same. Resistors R15 and R17 connect the AIN0 and AIN1 pins of chip U5 to pins 1 of two operational amplifiers respectively, and are output to the corresponding interfaces PB10 and PB11 pins of the STM32F103RCT6 single-chip microcomputer through IIC after chip conversion.

[0039] As a preferred embodiment, in the present application, the power interface of the power module is connected to the input pin VIN of the chip U6 via the fuse F1, the positive pole of the power filter capacitor C23 is connected to the +12V voltage line, the negative pole is connected to PGND, and the filter capacitor C24 is connected in parallel with the capacitor C23. The chip FB pin is connected between R22 and R23, the output voltage is monitored and fed back to the controller chip. The chip SW pin is connected to the inductor L1 and then outputs +5V voltage. The capacitors C26, C27 and the diode D3 are connected between +5V and PGND to play a filtering and voltage stabilizing role. U7 is an AMS1117 chip, +5V is connected to the VIN pin, and the OUT pin outputs a +3.3V voltage. The filter capacitors C28 and C29 are respectively connected between VIN, VOUT and GND. U8 uses the LM2662 chip, the +5V voltage is connected to the chip V+ pin, the capacitor C31 is connected between the chip 2 and 4 pins, and the chip OUT pin outputs a corresponding negative voltage to power the operational amplifier. Two 0Ω resistors R24 and R25 are connected between the two ground pins to reduce the interference of the digital ground on the analog ground.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. Metering pump frequency control system, characterized in that: include: STM32F103RCT6 microcontroller, flow monitoring module, metering pump control module, sensor detection module, display module and power module; The output end of the flow monitoring module is connected to the input end of the STM32F103RCT6 single chip microcomputer to obtain the water flow information entering the system; The input end of the metering pump control module is connected to the output end of the STM32F103RCT6 single chip microcomputer, and is used to control the working frequency of the metering pump and adjust the delivery amount of the stock liquid; The output end of the sensor detection module is connected to the input end of the STM32F103RCT6 single-chip microcomputer, and is used to feed back the detected pH value and ORP value to the single-chip microcomputer; The output end of the power module is connected to the STM32F103RCT6 single chip microcomputer, the flow monitoring module, the metering pump control module, and the sensor detection module, and is used to provide power supply voltage to each module.

2. The metering pump frequency control system according to claim 1, characterized in that: The output signal of the flow monitoring module is connected to the PA10 pin of the GPIO port of the STM32F103RCT6 chip through the current limiting resistor R7. One end of the pull-up resistor R6 is connected to the +12V voltage, and the other end is connected to the output pin of the flow monitoring module, which is used to clamp the uncertain signal to a high level. At the same time, the filter capacitor C12 is connected in parallel with the electrostatic protection diode D1, one end is connected to the signal output, and the other end is grounded, which is used to eliminate high-frequency noise and surge voltage interference in the signal.

3. The metering pump frequency control system according to claim 1, characterized in that: The PA11 interface of the STM32F103RCT6 single-chip computer outputs a pulse signal, which is connected to pin 2 of the optocoupler through a current limiting resistor R9, pin 1 of the optocoupler is connected to VCC, pin 3 is grounded, and the frequency signal is output from pin 4, and is input into the metering pump control module after passing through the current limiting resistor R11. The filter capacitor C13 and the pull-down resistors R8 and R10 are connected in parallel, one end is connected to pin 4 of the optocoupler, and the other end is grounded. The anode of the voltage regulator diode D2 is grounded, and the cathode is connected to pin 4 of the optocoupler to protect the light-emitting diode of the optocoupler from electrostatic interference.

4. The metering pump frequency control system according to claim 1, characterized in that: The sensor detection circuit detects signals through the pH sensor and the ORP sensor, amplifies the signals through the operational amplifiers U3.1 and U4.1 respectively, connects the output signal to the ADS1115 chip, and outputs it to the GPIO interfaces PB10 and PB11 of the single-chip computer through the IIC after chip conversion. The capacitors C14-C21 are connected between the positive and negative voltages and the analog ground to play a power supply filtering role. The resistors R13 and R14 are connected in series, and the resistors R18 and R19 are connected in series to control the amplification factors of the operational amplifiers U3.1 and U4.1 respectively.

5. The metering pump frequency control system according to claim 1, characterized in that: The power module connects the +12V voltage to the 5-pin of the chip U6 through the fuse F1, and the 3-pin of the chip U6 outputs a +5V voltage after the inductor L1 continues the current. The capacitors C23, C24, C26, and C27 act as power supply filters. The voltage regulator diode D3 is connected to the 3-pin of the chip U6 and PGND for stabilizing the voltage. The chip U7 inputs a +5V voltage and outputs a +3.3V voltage. The chip U8 is used to convert the +5V input voltage into a negative voltage of -5V. The resistance values ​​of the resistors R24 and R25 are both 0Ω, and they are connected between two different ground pins to reduce the interference of the digital ground on the analog ground.

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