Device and method for measuring voltage and temperature of electrolytic cell chamber of water electrolysis hydrogen production equipment

Abstract

The invention relates to a device and a method for measuring voltage and temperature of electrolytic cell cells of water electrolysis hydrogen production equipment, which are used for measuring voltage and temperature of each electrolytic cell in an electrolytic cell. Comprising a terminal strip, a temperature measuring resistor and a high-precision fixed resistance resistor, the ith electrolysis cell corresponds to two terminals on the terminal row, namely a first terminal and a second terminal, the first terminal is connected to a wire connection point arranged on a polar plate of the ith electrolysis cell through a wire, and the second terminal is connected to one end of a temperature sampling resistor through a wire; the other end of the temperature sampling resistor is connected to the other wire connection point arranged on the ith electrolysis cell polar plate through a wire; and the high-precision fixed-resistance resistor is connected between the second terminal of the ith electrolysis cell and the first terminal of the (i + 1) th electrolysis cell. According to the invention, the real-time monitoring of the voltages of all cells of the electrolytic cell and the temperature of each polar plate is realized, and the problems of single monitoring parameter and cable redundancy in the prior art are solved.

Description

Technical Field

[0001] This invention belongs to the field of operation monitoring technology for water electrolysis hydrogen production equipment, specifically involving the acquisition and protection technology of core operating parameters of the electrolyzer. It focuses on the real-time monitoring of the voltage of a single electrolysis chamber and the temperature of each electrode plate inside the electrolyzer, and is applicable to the safe and stable operation management of the electrolyzer in large-scale water electrolysis hydrogen production equipment. Background Technology

[0002] Electrolyzer parameter monitoring technology is mainly applied to the electrolyzer system of water electrolysis hydrogen production equipment. During the operation of the electrolyzer, the voltage of each electrolysis cell and the temperature of each electrode plate are key operating parameters: when a short circuit fault occurs in the electrolyzer, the voltage of the faulty cell will drop rapidly, and the temperature of the corresponding electrode plate will rise rapidly. Therefore, real-time monitoring of these two parameters and timely shutdown based on abnormal information are core requirements for ensuring the stable operation of the electrolyzer.

[0003] Currently, the electrolyzers used in industrial hydrogen production equipment typically have hundreds or even 300-400 electrode plates (corresponding to 300-400 electrolysis chambers), but existing monitoring methods have significant limitations:

[0004] Insufficient monitoring scope: Only the total voltage, inlet temperature, and outlet temperature of the electrolytic cell are monitored, which cannot cover the voltage of all cells and the temperature of the electrodes in real time. Short circuits and other faults in the electrolytic cell often occur in a single cell. The voltage drop and electrode temperature rise in the faulty cell will not cause significant changes in the total voltage or the inlet and outlet temperatures of the cell, making the fault difficult to detect. This may lead to the insulation gaskets being damaged due to excessively high temperature of individual electrodes, causing direct electrode connection and triggering a larger safety accident.

[0005] Excessive cable usage: Traditional small cell voltage and electrode temperature acquisition are independent systems. Measuring the voltage between two electrodes requires two cables, and measuring the temperature of one electrode requires two cables. For large electrolytic cells with 300-400 small cells, this will generate a massive amount of cables, increasing the complexity and cost of the equipment. Summary of the Invention

[0006] In view of this, the present invention proposes a device and method for measuring the voltage and temperature of the electrolyzer compartments in a water electrolysis hydrogen production equipment. This invention overcomes the limitations of existing methods that only monitor the total voltage and inlet / outlet temperature, achieving real-time monitoring of the voltage of all compartments in the electrolyzer and the temperature of each electrode plate, thus solving problems such as single monitoring parameters and redundant cables in existing technologies.

[0007] The specific technical solution is as follows:

[0008] The water electrolysis hydrogen production equipment includes a voltage and temperature measuring device for each electrolysis cell, used to measure the voltage and temperature of each electrolysis cell. It also includes a terminal block, a temperature-sensing resistor, and a high-precision fixed-value resistor. The i-th electrolysis cell has two terminals on the terminal block: a first terminal and a second terminal. The first terminal is connected via a wire to a wire connection point on the electrode plate of the i-th electrolysis cell. The second terminal is connected via a wire to one end of the temperature-sensing resistor, and the other end of the temperature-sensing resistor is connected via a wire to another wire connection point on the electrode plate of the i-th electrolysis cell. The high-precision fixed-value resistor is connected between the second terminal of the i-th electrolysis cell and the first terminal of the (i+1)-th electrolysis cell.

[0009] Furthermore, the temperature sensing resistor is of the type with inherently high resistance, which is used to effectively avoid burnout due to its own power value exceeding the rated range, thereby preventing the induction of short circuit faults between the plates.

[0010] Furthermore, it also includes a data acquisition module, which acquires the voltage between the first terminals of the i-th and i+1-th electrolytic cells, i.e., the cell voltage of the i-th electrolytic cell, and acquires the voltage between the second terminal of the i-th electrolytic cell and the first terminal of the i+1-th electrolytic cell, i.e., the voltage across the high-precision fixed-value resistor.

[0011] Furthermore, it also includes a data processing module, which is used to calculate the temperature of the electrolysis chamber based on the relationship between the resistance value of the temperature sampling resistor and the temperature.

[0012] Furthermore, it also includes screen display and industrial communication interfaces.

[0013] A method for measuring the voltage and temperature of the electrolytic cell in a water electrolysis hydrogen production equipment includes: drawing two wires, referred to as the first wire and the second wire, from the electrode plate of each electrolysis cell; connecting a temperature-sensing resistor and a high-precision fixed-value resistor in series between the second wire of the i-th electrolysis cell and the first wire of the (i+1)-th electrolysis cell; measuring the voltage between the two first wires of the i-th and (i+1)-th electrolysis cells, which is the cell voltage of the i-th electrolysis cell; using the cell voltage of the i-th electrolysis cell to drive the temperature-sensing resistor and the high-precision fixed-value resistor, and measuring the voltage between the second wire of the i-th electrolysis cell and the first wire of the (i+1)-th electrolysis cell, which is the voltage across the high-precision fixed-value resistor; obtaining the actual voltage value across the temperature-sensing resistor through difference calculation; obtaining the resistance value of the temperature-sensing resistor by utilizing the fact that the current flowing through the series resistor is equal; and then obtaining the temperature of the i-th electrolysis cell based on the calculated relationship between the resistance value of the temperature-sensing resistor and the temperature.

[0014] Beneficial effects

[0015] 1. More timely and accurate fault detection, enhancing safety early warning capabilities: Breaking through the limitations of traditional equipment that only monitors the total voltage and inlet and outlet temperatures of the electrolytic cell, it can monitor the voltage of all chambers and the temperature of each electrode plate in real time. It can quickly detect local faults such as short circuits in individual chambers (e.g., voltage drop) and abnormal temperature rises of individual electrodes (e.g., temperature surge), avoiding missed faults due to local problems not causing significant changes in overall parameters, and proactively avoiding potential safety hazards.

[0016] 2. Reduce equipment complexity and cost while ensuring parameter acquisition accuracy: Addressing the cable redundancy issue of traditional independent acquisition systems, an innovative method couples temperature and chamber voltage measurements, reducing cable usage by one-third compared to traditional solutions. For large electrolytic cells with 300-400 chambers, this significantly reduces equipment wiring complexity, lowers cable procurement and maintenance costs, while ensuring the accuracy of voltage and temperature parameter acquisition remains unaffected.

[0017] 3. Prevent accidents from escalating and ensure stable equipment operation: It has the function of triggering shutdown based on abnormal information. When abnormal conditions such as sudden drop in cell voltage or sudden rise in electrode temperature are detected, the shutdown procedure can be initiated in time. This effectively prevents larger accidents caused by problems such as damage to the insulating gasket due to excessive temperature of individual electrodes or direct connection of electrodes. It realizes a closed loop of "real-time monitoring of all parameters - timely shutdown of abnormalities - ensuring stable operation" and improves the reliability of electrolytic cell operation. Attached Figure Description

[0018] Figure 1 A schematic diagram of the device structure described in this invention;

[0019] Figure 2 1. Schematic diagram of the measurement principle of the device described in this invention;

[0020] Figure 3 1. Schematic diagram of the existing device structure. Detailed Implementation

[0021] The device described in this invention is as follows Figure 1As shown, the measuring devices and methods for all tested electrolytic cell chambers are the same. The following detailed description takes the measurement of voltage and temperature of test chamber 1 as an example. Two wire connection points are set on the electrode plate of test chamber 1. One wire is directly led out to terminal 1 of the terminal block, and the other wire is led out from the electrode plate and connected to one end of temperature sampling resistor T1. The other end of temperature sampling resistor T1 is connected to terminal 2 of the terminal block. T1 temperature sampling resistor is the temperature sensor of test chamber 1. R1 is a high-precision fixed resistance resistor, and its two ends are connected to terminals 1 and 2 of the terminal block, respectively. Electrolytic cell No. 2 is adjacent to electrolytic cell No. 1. Two wire connection points are also set on the electrode plate of electrolytic cell No. 2. Similarly, one wire is led directly to terminal 3 of the terminal block, and the other wire is led from the electrode plate and connected to one end of the T2 temperature sampling resistor. The other end of the T2 temperature sampling resistor is connected to terminal 4 of the terminal block. The T2 temperature sampling resistor serves as the temperature sensor for electrolytic cell No. 2. R2 is a high-precision fixed-value resistor, with its two ends connected to terminals 4 and 5 of the terminal block, respectively. The wiring method for the other electrolytic cell chambers is the same; each electrolytic cell chamber has two wires leading out, corresponding to two terminals on the terminal block. Using a differential voltage measurement circuit, the voltage V13 between terminals 1 and 3 and the voltage V23 between terminals 2 and 3 are measured respectively. V13 is the voltage of the cell in electrolytic cell 1 being tested. The temperature of cell 1 is calculated by measuring the resistance change of resistor T1. The resistance of T1 is calculated as follows: the temperature sampling resistor T1 and the high-precision fixed resistor R1 are connected in series, and the current flowing through them is the same. The voltage across the high-precision fixed resistor R1 is V23, and the voltage across the temperature sampling resistor T1 is V13 - V23. Therefore, the formula for calculating the resistance of the temperature sampling resistor T1 can be derived as follows:

[0022] T1 = (V13 - V23) * R1 / V23

[0023] The resistance value can be calculated using the above formula. The change in resistance corresponds one-to-one with the change in temperature, and can then be converted into temperature data.

[0024] The conversion formula depends on the type of temperature sampling resistor. For example, temperature sampling resistors include platinum resistance thermometers such as PT100 and PT1000, or thermistors such as 5K ohms, 10K ohms, 50K ohms, and 100K ohms. The formulas for the change in resistance value and temperature are different for different types of temperature sampling resistors.

[0025] Furthermore, since the temperature is measured by directly connecting the temperature sampling resistor to the two electrolytic plates, the temperature sampling resistor must have a large inherent resistance value when selected. Otherwise, it may exceed the power value of the temperature sampling resistor, causing the temperature sampling resistor to burn out and resulting in a short circuit between the plates. For example, a thermistor with a resistance of 10K ohms or higher should be selected.

[0026] The selection of high-precision fixed-value resistors should be consistent with the resistance value of the temperature sampling resistor at standard temperatures. For example, for a 10K ohm thermistor, the fixed-value resistor should be 10K ohms.

[0027] This invention measures temperature by utilizing a voltage of approximately 2V between the plates of adjacent electrolytic cell chambers after the electrolytic cell starts operating. Two resistors are added between the plates: one is a platinum resistance thermometer used to measure the temperature, and the other is a fixed-value high-precision resistor used to calculate the resistance value of the platinum resistance thermometer.

[0028] Figure 2 This is a schematic diagram of the measuring device. Each measurement of the voltage and plate temperature of an electrolytic cell requires measuring the voltage signals from two channels. These two voltage signals need to be converted from the differential voltage signals between the two points to be measured into single-ended voltage signals that share a common ground with the microcontroller, allowing the microcontroller to acquire the signals.

[0029] After sampling the analog voltage signal, the data processing step begins. In this step, the cell voltage and electrode temperature signals are calculated using formulas.

[0030] After data acquisition and processing to obtain all the voltage and temperature signals that need to be measured, the data can be displayed on the screen of this device. At the same time, this device supports TCP and 485 interfaces and standard industrial communication protocols, such as Modbus TCP or Modbus RTU, so that external devices can directly read the parameters.

[0031] This device uses a method of fixing the cable and temperature sensor by drilling holes. The cable is fixed by inserting a banana plug directly into it. The temperature sensor is a miniature platinum resistance thermometer or thermistor. The platinum resistance thermometer or thermistor is inserted into the hole to measure the temperature inside the electrode plate.

[0032] The specific operating steps for this device are as follows:

[0033] S1. Drill holes in the electrolytic cell, insert a banana head and lead out wires to connect the electrolytic cell plates to the terminal block of this device;

[0034] S2. Drill a hole in the electrolytic cell and insert a temperature sampling resistor. One end of the cable of the temperature sampling resistor in Method 1 needs to be connected to the electrode plate of the electrolytic cell, and the other end of the cable needs to be connected to the terminal block of the device. The platinum resistance of Method 2 needs to be wrapped with Teflon or other insulating and corrosion-resistant materials to prevent the cable from short-circuiting with the electrode plate of the electrolytic cell. The two cable ends are directly connected to the terminal block of the device.

[0035] S3. Connect all wires to the external terminal block of this device according to the principles in methods 1 and 2 respectively;

[0036] S4. Electrolytic cell startup: After this device is powered on, it can measure the cell voltage and plate temperature of the electrolytic cell.

[0037] S5 allows you to observe all measurement results on the local screen, and also allows you to remotely read all parameters via TCP or 485 ports.

[0038] Figure 3 Existing devices for measuring the voltage and temperature of the cell in an electrolytic cell under test. For example... Figure 3 As shown, each electrolytic cell electrode plate has three wire connection points. One wire leads directly to the terminal, and the other two wires are drawn from the thermistor or platinum resistance thermometer. In this scheme, the measurement of the cell voltage and temperature is isolated. The cell voltage is measured by one wire leading from each electrode plate, measuring the electrolytic cell voltage between the electrode plates. The temperature is measured using a 3.3V voltage signal inside the measuring device, which drives the platinum resistance thermometer R1 and the measuring resistor R2. The specific calculation formula is as follows:

[0039] T1 = V23 * R1 / (3.3 - V23)

[0040] This method uses the power supply on the circuit board to drive the temperature sampling resistor, samples the voltage signal, converts it into the resistance value of the temperature sampling resistor, and then converts it into temperature parameters. The advantages are that the temperature signal can be detected normally in both the off and running states of the electrolytic cell; there are no restrictions on the selection of the temperature sensor, and any type of resistive temperature sensor can be used. The disadvantage is that three wires need to be printed for each electrode plate.

[0041] and Figure 3 Compared to the technical solutions shown, the advantages of this invention are that it requires fewer wires; only two wires are needed to connect each electrode to measure the voltage of the electrolytic cell chamber and the temperature of the electrode. The disadvantage is that the temperature can only be measured when the electrolytic cell is in operation. If the electrolytic cell is shut down, there is no voltage between the electrodes, making it impossible to drive the platinum resistance thermometer and thus measure the temperature signal.

Claims

1. A voltage and temperature measuring device for the electrolytic cell chambers of a water electrolysis hydrogen production equipment, used to measure the voltage and temperature of each electrolytic cell in the electrolytic cell, characterized in that: It also includes a terminal block, a temperature sensing resistor, and a high-precision fixed-value resistor; the i-th electrolytic cell has two terminals on the terminal block, namely the first terminal and the second terminal. The first terminal is connected to a wire connection point on the electrode plate of the i-th electrolytic cell via a wire, and the second terminal is connected to one end of the temperature sampling resistor via a wire. The other end of the temperature sampling resistor is connected to another wire connection point on the electrode plate of the i-th electrolytic cell via a wire; the high-precision fixed-value resistor is connected between the second terminal of the i-th electrolytic cell and the first terminal of the (i+1)-th electrolytic cell.

2. The voltage and temperature measuring device for the electrolytic cell chamber of the water electrolysis hydrogen production equipment according to claim 1, characterized in that: The temperature sensing resistor is of the type with inherently high resistance value, which is used to effectively avoid burnout due to its own power value exceeding the rated range, thereby preventing the induction of short circuit faults between the plates.

3. The voltage and temperature measuring device for the electrolytic cell chamber of the water electrolysis hydrogen production equipment according to claim 1, characterized in that: It also includes a data acquisition module, which acquires the voltage between the first terminals of the i-th and i+1-th electrolytic cells, i.e., the cell voltage of the i-th electrolytic cell, and acquires the voltage between the second terminal of the i-th electrolytic cell and the first terminal of the i+1-th electrolytic cell, i.e., the voltage across the high-precision fixed-value resistor.

4. The voltage and temperature measuring device for the electrolytic cell chamber of the water electrolysis hydrogen production equipment according to claim 1, characterized in that: It also includes a data processing module, which is used to calculate the temperature of the electrolysis chamber based on the relationship between the resistance value of the temperature sampling resistor and the temperature.

5. The apparatus according to any one of claims 1-4, characterized in that: It also includes screen display and industrial communication interfaces.

6. A method for measuring the voltage and temperature of the electrolytic cell in a water electrolysis hydrogen production equipment, characterized in that: Two wires, designated as the first wire and the second wire, are drawn from the electrode plates of each electrolysis chamber. A temperature-sensing resistor and a high-precision fixed-value resistor are connected in series between the second wire of the i-th electrolysis chamber and the first wire of the (i+1)-th electrolysis chamber. The voltage between the two first wires of the i-th and (i+1)-th electrolysis chambers is measured, which is the chamber voltage of the i-th electrolysis chamber. The chamber voltage of the i-th electrolysis chamber is used to drive the temperature-sensing resistor and the high-precision fixed-value resistor, and the voltage between the second wire of the i-th electrolysis chamber and the first wire of the (i+1)-th electrolysis chamber is measured, which is the voltage across the high-precision fixed-value resistor. The actual voltage value across the temperature-sensing resistor is obtained through difference calculation. The resistance value of the temperature-sensing resistor is obtained by using the fact that the current flowing through the series resistor is equal. Then, the temperature of the i-th electrolysis chamber is obtained according to the calculation relationship between the resistance value of the temperature-sensing resistor and the temperature.

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