Online pH value monitoring device for phase modifier external cold water system

Abstract

The invention relates to the technical field of power system management, in particular to a pH value online monitoring device for a phase modifier external cooling water system. Comprising a pH composite electrode unit which is used for measuring the activity of hydrogen ions in a solution; the interface circuit unit is used for receiving the electric signal transmitted by the pH composite electrode unit and amplifying the electric signal; the control module is used for receiving the electric signal transmitted by the interface circuit unit, converting the electric signal into digital quantity and carrying out data processing; the display module is used for displaying and outputting the measurement result; the keyboard module is used for inputting parameter adjustment and mode setting; the battery module is electrically connected with the control module, and the battery module is used for providing working power for other components; the stability and anti-interference performance of data acquisition are improved, the pH value of the water quality of external cold water is dynamically monitored, the alkalinity of the water quality of the external cold water meets the requirement, and the pH measuring device is high in precision, high in stability, portable, easy to use and easy to maintain.

Description

Technical Field

[0001] The invention relates to the technical field of power system management, and in particular to an online monitoring device for pH value of a phase-shifting external cooling water system. Background Art

[0002] The function of the external cooling water system of the condenser station is to send cooling water to exchange heat with the cooling water cooler, oil system cooler and air cooler in the condenser stator and rotor, so as to ensure that the oil and water of the condenser and the air inside the condenser are within the qualified temperature range. The scaling of the external cooling water of the condenser is that the pH index cannot be accurately monitored, because the pH value of water quality is an important indicator to measure the acidity and alkalinity of water. The pH value of water quality also directly affects many processes in industrial production, such as cooling water of other systems and boiler water. The reason for the fluctuation of pH value in the external cooling water system may be due to external factors. For example, when the circulating cooling water system is contaminated by pollutants or other chemicals in the atmosphere, these pollutants will change the chemical composition of the circulating cooling water, resulting in fluctuations in pH value. In addition, the gas in the circulating cooling water system may also affect the pH value, for example, the dissolution of carbon dioxide will cause the pH value to drop. Internal factors of the external cooling water system may also cause fluctuations in pH value. For example, metal corrosion in the external cooling water system will release some metal ions, which will change the acidity and alkalinity of water and affect the pH value. In addition, the growth of microorganisms in the external cooling water system may also cause changes in pH value. The metabolites of microorganisms will change the chemical composition of water, thus affecting the pH value. The pH meter on the market is the most widely used chemical analysis instrument in the laboratory, which measures the pH value in the aqueous solution. It has been widely used in agriculture, industry, food, pharmaceuticals, biology, environmental protection, marine and other fields. With the continuous development of modern chemical industry, environmental protection, medical and other fields, the requirements for water quality monitoring are becoming increasingly stringent. And pH value plays an important role as the main reference indicator for water quality monitoring. In the process of pH measurement, there are many factors that affect its measurement accuracy, among which the aging of the electrode, the temperature change of the measured solution and the stability of the circuit all bring certain errors to the measurement. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide an online monitoring device for the pH value of a phase-shifting external cooling water system, improve the stability and anti-interference of data acquisition, dynamically monitor the pH value of the external cooling water quality so that the alkalinity of the external cooling water quality meets the requirements, and provide a high-precision, high-stability, portable, easy-to-use and easy-to-maintain pH measuring device.

[0004] The object of the present invention is achieved in this way: an online monitoring device for pH value of a phase-shifting external cooling water system comprises: A pH composite electrode unit, wherein the pH composite electrode unit is used to measure the activity of hydrogen ions in a solution; An interface circuit unit, the interface circuit unit is electrically connected to the pH composite electrode unit, the interface circuit unit receives the electrical signal transmitted by the pH composite electrode unit and amplifies it; A control module, the control module is electrically connected to the interface circuit unit, the control module receives the electrical signal transmitted by the interface circuit unit, converts the electrical signal into a digital quantity and performs data processing; A display module, the display module is electrically connected to the control module, and the display module is used to display and output the measurement results; A keyboard module, the keyboard module is electrically connected to the control module, and the keyboard module is used for inputting parameter adjustment and mode setting; A battery module, the battery module is electrically connected to the control module, and the battery module is used to provide working power for other components.

[0005] Furthermore, the pH composite electrode unit includes a pH electrode and a reference electrode. The pH electrode is used to measure the activity of hydrogen ions in the solution and is a core component of the pH meter. The reference electrode is used to provide a stable reference potential to ensure the accuracy of the measurement results.

[0006] Furthermore, the pH composite electrode unit transmits a thermistor resistance signal of the measured temperature and a voltage signal corresponding to the pH value of the solution to the interface circuit unit.

[0007] Furthermore, the control module includes a microprocessor chip, and the microprocessor chip is a HC32L176 series chip.

[0008] Furthermore, a thermistor for measuring temperature is arranged in the pH composite electrode unit, and the resistance value of the thermistor changes with the temperature. The pH composite electrode unit transmits the changed resistance value signal to the interface circuit unit.

[0009] Furthermore, the interface circuit unit processes the received resistance value signal transmitted by the pH composite electrode unit and converts it into a corresponding voltage value, and transmits it to the control module.

[0010] Furthermore, a key interface circuit is provided in the keyboard module, and the keyboard module includes a plurality of keys. When a key is pressed, the key interface circuit generates a low level to trigger a pulse signal and sends it to the processor in the control module for identification feedback.

[0011] Furthermore, the display module includes a display screen, the material of which is an LCD screen, and the display module displays the pH value and temperature transmitted by the control module in real time.

[0012] Furthermore, a DC 24V large-capacity rechargeable battery is provided in the power module.

[0013] Beneficial effects of the present invention: The on-line monitoring device for pH value of the phase-shifting outdoor cooling water system of the present invention adopts surface mount components in the circuit design, which reduces the volume while ensuring the functions, and meets the requirements of portability. The HC32L176 series single-chip microcomputer is used for data processing to realize temperature compensation, automatic calibration and other processes, thereby improving the accuracy of measurement and reducing errors. Low power consumption is taken into consideration in the design of software and hardware, and this issue is also considered when selecting components and processors, so that the power consumption of the entire instrument is relatively reduced. The instrument has auxiliary functions such as manual temperature compensation, high and low alarms, and isolated RS485 transmission. Anti-interference measures are adopted in both hardware circuit and software program design to ensure the accuracy of measurement and improve the reliability of the instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention 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 only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 The figure is a schematic diagram of the pH value online monitoring device of the phase-shifting external cooling water system of the present invention.

[0016] Figure 2 Schematic diagram of the HC32L176 chip diagram in an embodiment of the present invention.

[0017] Figure 3 The diagram is a schematic diagram of a partial circuit of an interface circuit unit in an embodiment of the present invention.

[0018] Figure 4 It is a schematic diagram of a partial circuit design for temperature processing of an interface circuit unit in an embodiment of the present invention.

[0019] Figure 5 The diagram is a schematic diagram of a circuit diagram of a portion of a keyboard module key interface in an embodiment of the present invention.

[0020] Figure 6 It is a schematic diagram of a circuit showing an interface part in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that all directional indications in the embodiments of the present invention (such as up-down-left-right-front-back...) are only used to explain the relative position relationship - movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. The connection can be a direct connection or an indirect connection.

[0025] like Figure 1-6 As shown, the pH value online monitoring device of the phase-shifting external cooling water system of the present invention comprises: A pH composite electrode unit, wherein the pH composite electrode unit is used to measure the activity of hydrogen ions in a solution; An interface circuit unit, the interface circuit unit is electrically connected to the pH composite electrode unit, the interface circuit unit receives the electrical signal transmitted by the pH composite electrode unit and amplifies it; A control module, the control module is electrically connected to the interface circuit unit, the control module receives the electrical signal transmitted by the interface circuit unit, converts the electrical signal into a digital quantity and performs data processing; A display module, the display module is electrically connected to the control module, and the display module is used to display and output the measurement results; A keyboard module, the keyboard module is electrically connected to the control module, and the keyboard module is used for inputting parameter adjustment and mode setting; A battery module, the battery module is electrically connected to the control module, and the battery module is used to provide working power for other components.

[0026] The working principle of the pH online monitoring device is to rely on the sample solution to exchange ions with the liquid in the glass electrode (pH buffer) through the glass membrane to establish a potential difference that responds to the change in the activity of the hydrogen ions of the measured solution. Placing the pH-sensitive electrode and the reference electrode in the same solution forms a primary cell, the potential of which is the algebraic sum of the potentials of the glass electrode and the reference electrode. E cell = E reference + E glass. If the temperature is constant, the potential of this cell changes with the pH value of the solution to be measured. It is difficult to measure the potential generated by the battery in the pH online monitoring device because its electromotive force is very small and the impedance of the circuit is very large; therefore, the signal must be amplified to make it sufficient to drive a standard millivoltmeter or milliammeter. The function of the ammeter is to amplify the potential of the primary cell several times, and the amplified signal is displayed by the ammeter. The degree of deflection of the pointer of the traditional ammeter indicates the strength of the signal it drives. For the needs of use, the dial of the pH meter ammeter is engraved with the corresponding pH value; while the pH online monitoring device designed this time directly displays the pH value in digital form.

[0027] Furthermore, in one embodiment, the pH composite electrode unit includes a pH electrode and a reference electrode. The pH electrode is used to measure the activity of hydrogen ions in a solution and is a core component of a pH meter. The reference electrode is used to provide a stable reference potential to ensure the accuracy of the measurement results.

[0028] Furthermore, in one embodiment, the pH composite electrode unit transmits a thermistor resistance signal for measuring temperature and a voltage signal corresponding to the pH value of the solution to the interface circuit unit.

[0029] Furthermore, in one embodiment, the control module includes a microprocessor chip, and the microprocessor chip is a HC32L176 series chip.

[0030] The microprocessor chip is the core of the pH online monitoring device. Its selection determines the intelligence level of the pH online monitoring device and the complexity of its structure. The main principles for selecting a microprocessor chip are: operation word length, addressing range, execution speed, power consumption, etc.

[0031] The HC32L176 series chip is a high-performance microcontroller. Its ultra-low power consumption, high-performance CPU, rich peripheral integration, high integration and reliability, powerful storage capacity and good versatility make it a significant advantage in the field of microcontrollers.

[0032] 1) Ultra-low power consumption: The power consumption in deep sleep mode is extremely low, which helps to extend the battery life of portable measurement systems. The wake-up time is only 4μs, making mode switching more flexible and efficient, and the system more responsive.

[0033] 2) High-performance CPU: Based on the ARM Cortex-M0+ core, the main frequency is up to 48MHz, providing sufficient computing power for various applications.

[0034] 3) Rich peripheral integration: Integrates 12-bit 1Msps high-precision SARADC, 1 12-bit DAC, comparator, op amp, high-performance PWM timer, LCD display and other peripherals. Supports multiple UART, SPI, I2C and other rich communication interfaces to facilitate communication with other devices.

[0035] 4) High integration and high reliability: High integration design reduces system complexity and development difficulty. Built-in AES, TRNG and other information security modules ensure data security and integrity, and have high anti-interference capabilities, ensuring stable operation of the system in various environments.

[0036] 5) Storage capacity: It has 128K bytes of Flash memory and 16K bytes of RAM memory, supports ISP, ICP, IAP and other programming methods, and is convenient for program development and updating. The Flash memory has a write-erase protection function, and the RAM memory comes with parity check, which enhances the stability of the system.

[0037] 6) Versatility: With mature Keil & IAR debugging and development software, it supports C language and assembly language, and is easy to program and debug. A wide range of pin configuration options (such as 88IO / 100PIN, 72IO / 80PIN, etc.) can meet different application requirements.

[0038] In summary, the HC32L176MATA chip has significant advantages in the field of microcontrollers with its ultra-low power consumption, high-performance CPU, rich peripheral integration, high integration and high reliability, powerful storage capacity and good versatility.

[0039] Furthermore, in one embodiment, a thermistor for measuring temperature is provided in the pH composite electrode unit, and the resistance of the thermistor changes with temperature. The pH composite electrode unit transmits a changed resistance value signal to the interface circuit unit.

[0040] Furthermore, in one embodiment, the interface circuit unit processes and converts the received resistance value signal transmitted by the pH composite electrode unit into a corresponding voltage value, and transmits it to the control module.

[0041] The electrode part adopts glass composite electrode, which has good response speed and stability. The signal output from the signal electrode and the reference electrode of the composite pH electrode is voltage. At a certain temperature, as long as the voltage value is known, the pH value of the solution can be obtained. The measurement is actually the measurement of voltage signal. The signal acquisition circuit is the key of the pH online monitoring device. Since the internal resistance of the composite electrode is very high, the key to the measurement circuit is to achieve high impedance input. To achieve high impedance input, the operational amplifier must first have a very high input impedance. Generally, the internal resistance of the glass electrode is very high. When the input impedance of the operational amplifier is higher than the internal resistance of the sensor, the correct voltage signal can be obtained.

[0042] The signal output from the sensor electrode is the relative voltage between the signal electrode and the reference electrode. This device uses a composite electrode, and the sensor reference electrode is a neutral solution. That is, when the pH value of the measured solution is 7, its output voltage is theoretically 0. In other cases, the output voltage changes positively or negatively according to the different acidity and alkalinity of the solution. According to the working principle of the operational amplifier, the input of negative voltage is inconsistent with the single power supply. However, because the output signal is the voltage difference relative to the reference electrode, a suitable voltage value is given to the reference electrode (pH-input), which can ensure that the voltage of the signal electrode (pH+input) is always positive, and the single power supply of the operational amplifier can meet the requirements. The electrode output voltage does not meet the requirements, and the conversion input requires that the basic amplification power of the operational amplifier can make it reach the voltage range required for analog-to-digital conversion, and then it can be sent to the single-chip microcomputer for data processing.

[0043] The pH sensor electrode used in this device contains a thermistor for measuring temperature. Its resistance changes with temperature, but the resistance value is not the desired signal. The focus of the temperature signal processing circuit is to convert the changing resistance value into a corresponding changing voltage value, which is processed to change to the voltage value required for the conversion and sent to the microprocessor.

[0044] At the same time, the interface circuit retains the RS485 communication expansion interface, manual temperature compensation and high and low alarm contacts. If you want to expand this function later, you can directly expand this function through the interface.

[0045] Furthermore, in one embodiment, a key interface circuit is provided in the keyboard module, and the keyboard module includes a plurality of keys. When a key is pressed, the key interface circuit generates a low level to trigger a pulse signal and sends it to the processor in the control module for identification feedback.

[0046] From the initial function setting, the pH online monitoring device needs five buttons: menu, return, confirm and two direction keys. The button interface circuit design can generate a low level when the button is pressed to trigger a pulse signal to be sent to the processor for identification feedback, but jitter will occur during actual button operation. That is, when the button is pressed and released, the button contact cannot react in time and cannot be connected or disconnected immediately. Key jitter may cause the microprocessor to recognize a single key operation as multiple operations. Software programs can be used to eliminate jitter in the device design.

[0047] Furthermore, in one embodiment, the display module includes a display screen, the material of which is an LCD screen, and the display module displays the pH value and temperature transmitted by the control module in real time.

[0048] Because it is necessary to display pH value, temperature, etc. in real time, the displayed data types will appear in the combination of Chinese characters, numbers and letters, so the requirements for the display module are relatively high, so the material selection uses an LCD screen. The single-chip microcomputer interface is connected to the data and clock ports of the liquid crystal display module respectively. The working current of the module only meets the requirements of low power consumption when working. It is easy to use and only occupies two pins of the single-chip microcomputer, which simplifies the system design.

[0049] Furthermore, in one embodiment, a DC 24V large-capacity rechargeable battery is provided in the power module.

[0050] The design of the power module is equipped with a large-capacity rechargeable battery, abandons the 220V power supply, and adopts a DC 24V power supply that is portable and convenient to power. It is not restricted by regional usage and location, ensuring long-term stable operation.

[0051] In summary, the circuit design of the phase-shifting outdoor cooling water system online monitoring device of the present invention adopts surface mount components in terms of components, which reduces the volume while ensuring the functionality, and meets the requirement of portability. The HC32L176 series single-chip microcomputer is used for data processing to realize temperature compensation, automatic calibration and other processes, thereby improving the measurement accuracy and reducing errors. Low power consumption is taken into consideration in the design of software and hardware, and this issue is also considered when selecting components and processors, so that the power consumption of the entire instrument is relatively reduced. The instrument has auxiliary functions such as manual temperature compensation, high and low alarms, and isolated RS485 transmission. Anti-interference measures are adopted in both hardware circuit and software program design to ensure the measurement accuracy and improve the reliability of the instrument.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. The online monitoring device for pH value of the external cooling water system of the phase regulator is characterized by: include: A pH composite electrode unit, wherein the pH composite electrode unit is used to measure the activity of hydrogen ions in a solution; An interface circuit unit, the interface circuit unit is electrically connected to the pH composite electrode unit, the interface circuit unit receives the electrical signal transmitted by the pH composite electrode unit and amplifies it; A control module, the control module is electrically connected to the interface circuit unit, the control module receives the electrical signal transmitted by the interface circuit unit, converts the electrical signal into a digital quantity and performs data processing; A display module, the display module is electrically connected to the control module, and the display module is used to display and output the measurement results; A keyboard module, the keyboard module is electrically connected to the control module, and the keyboard module is used for inputting parameter adjustment and mode setting; A battery module, the battery module is electrically connected to the control module, and the battery module is used to provide working power for other components.

2. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 1, characterized in that: The pH composite electrode unit comprises a pH electrode and a reference electrode. The pH electrode is used to measure the activity of hydrogen ions in a solution, and the reference electrode is used to provide a stable reference potential.

3. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 2, characterized in that: The pH composite electrode unit transmits a thermistor resistance signal for measuring temperature and a voltage signal corresponding to the pH value of the solution to the interface circuit unit.

4. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 1, characterized in that: The control module includes a microprocessor chip, and the microprocessor chip is a HC32L176 series chip.

5. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 3, characterized in that: The pH composite electrode unit is provided with a thermistor for measuring temperature. The resistance value of the thermistor changes with the temperature. The pH composite electrode unit transmits a changed resistance value signal to the interface circuit unit.

6. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 5, characterized in that: The interface circuit unit processes the received resistance value signal transmitted by the pH composite electrode unit and converts it into a corresponding voltage value, and transmits it to the control module.

7. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 1, characterized in that: A key interface circuit is provided in the keyboard module, and the keyboard module includes a plurality of keys. When a key is pressed, the key interface circuit generates a low level to trigger a pulse signal and sends it to the processor in the control module for identification feedback.

8. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 1, characterized in that: The display module includes a display screen, and its material is an LCD screen. The display module displays the pH value and temperature transmitted by the control module in real time.

9. The on-line monitoring device for pH value of a phase-shifting external cooling water system according to claim 1, characterized in that: The power module is provided with a DC 24V large-capacity rechargeable battery.

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