Method and device for dynamically adjusting conductivity of PEM electrolytic cell test system

Abstract

The invention discloses a method and device for dynamically adjusting the conductivity of a PEM electrolytic cell test system, and the method comprises the steps: triggering a water supplementing and draining program when the conductivity detected in the PEM electrolytic cell test system is higher than a first set value, opening a water supplementing pump, opening a water supplementing gas control valve and a water draining gas control valve in a pulse manner, and supplementing water and draining water at the same time, after the detected conductivity is lower than a second set value, stopping the water replenishing and draining program, and closing the water replenishing pump, the water replenishing air control valve and the water draining air control valve; the system has the advantages that water with impurity ions in the circulating pipeline is discharged, water of the water purifier is supplemented into the circulating water pipeline, the effect of reducing the conductivity is achieved, shutdown treatment is not needed, pressure relief and cooling, water supplementing after resin replacement, temperature rising and back pressure are not needed, and the time cost and the electric power gas production cost are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by electrolyzing water, and particularly to a method and device for dynamically adjusting the conductivity of a PEM electrolyzer test system. Background Art

[0002] In order to reduce greenhouse gas emissions and accelerate the energy transition, hydrogen energy, as a clean, green, and sustainable energy carrier, has gradually become a key direction for global energy development. Among various hydrogen production technologies, hydrogen production by electrolyzing water has received extensive attention because it can directly electrolyze water to produce hydrogen using renewable energy sources (such as wind energy and solar energy). The advantage of this technology is that through the electrolysis process driven by green electricity, zero-carbon emission production of hydrogen can be achieved.

[0003] The PEM (Proton Exchange Membrane) electrolysis water hydrogen production technology has an important position in hydrogen energy production due to its advantages such as high hydrogen purity, fast response, and high efficiency. Compared with traditional alkaline electrolysis of water, the PEM electrolysis water system can operate at a lower temperature, adapt to the fluctuations of renewable energy, and produce high-purity hydrogen, which is suitable for applications with high-purity hydrogen requirements such as fuel cells.

[0004] In the PEM electrolysis water hydrogen production technology, the conductivity of the circulating water is crucial for its electrical performance. Excessive conductivity will lead to an increase in the ion concentration in the electrolyte, reduce the resistance of the electrolyte, thereby causing an excessive current density, resulting in local overheating, increasing the risk of electrode corrosion, and shortening the service life of the system. Secondly, excessive conductivity may cause uneven distribution of the electric field in the electrolyzer, affecting the separation effect of hydrogen and oxygen and reducing the hydrogen purity. And high conductivity may also lead to a decrease in electrolysis efficiency, increase energy consumption, and affect the overall performance and operating cost of the system.

[0005] During the durability test, due to long-term cyclic electrolysis, the catalytic layer of the electrolyzer will fall off, resulting in a gradual increase in metal ions in the circulating water system, thereby causing an increase in conductivity and a decrease in electrolysis performance. Therefore, it is necessary to replace the resin and the circulating water, which requires shutdown for treatment, pressure relief and cooling. After replacing the resin, water replenishment, heating, and backpressure are required, increasing the time cost and the power generation cost of hydrogen production. Chinese Patent Publication No. CN117867590A discloses a PEM electrolyzer test system, but does not explain how to adjust the conductivity. Summary of the Invention

[0006] The technical problem to be solved by the present invention is that the existing method for adjusting the conductivity requires shutdown for treatment, pressure relief and cooling. After replacing the resin, water replenishment, heating, and backpressure are required, increasing the time cost and the power generation cost of hydrogen production.

[0007] The present invention solves the above technical problems through the following technical means: A method for dynamically adjusting the conductivity of a PEM electrolyzer test system, the method includes:

[0008] When the conductivity detected in the PEM electrolyzer test system is higher than the first set value, the makeup and drainage program is triggered. The makeup water pump is turned on, and the makeup water pneumatic control valve and the drainage pneumatic control valve are pulsed open. At the same time, makeup water and drainage are carried out until the detected conductivity is lower than the second set value, then the makeup and drainage program is stopped, and the makeup water pump, the makeup water pneumatic control valve, and the drainage pneumatic control valve are closed.

[0009] Beneficial effects: During the operation of the electrolyzer, the present invention adopts the method of online water replacement to discharge the water with impurity ions in the circulation pipeline, and at the same time replenish the water of the pure water machine into the circulation water pipeline, so as to achieve the effect of reducing conductivity. There is no need to stop the machine for treatment, nor to relieve pressure and cool down. After replacing the resin, makeup water, heating, and back pressure are carried out, reducing the time cost and the power generation cost.

[0010] Further, the method further includes:

[0011] If the pipeline pressure is detected within the set pressure limit range during the makeup and drainage process of the PEM electrolyzer test system, the makeup water pump, the makeup water pneumatic control valve, and the drainage pneumatic control valve are closed. When the detected pipeline pressure differs from the target value within the preset range, the makeup water pump, the makeup water pneumatic control valve, and the drainage pneumatic control valve are triggered to open again.

[0012] Further, the method further includes:

[0013] If the anode inlet temperature of the electrolyzer in the PEM electrolyzer test system is less than the first target temperature, the makeup water pump, the makeup water pneumatic control valve, and the drainage pneumatic control valve need to be closed. When the anode inlet temperature of the electrolyzer is greater than the second target temperature, the makeup water pump, the makeup water pneumatic control valve, and the drainage pneumatic control valve are triggered to open again, where the second target temperature is greater than the first target temperature.

[0014] Further, for the anode inlet temperature of the electrolyzer, the deionized water replenished is heated to the first target temperature by a two-stage temperature control method. The specific process is as follows: When the water is replenished into the separator, the temperature of the deionized water in the separator decreases. The water is circulated by the circulation water pump to the heater. The outlet temperature of the heater and the outlet target temperature value are input into the first PID controller to adjust the opening of the heater, so that the water replenished into the separator is heated. This is the first-stage temperature control. Since there is a certain distance of pipeline from the heater to the anode inlet of the electrolyzer and there is heat dissipation, the pipeline at the anode inlet of the electrolyzer is wound with an electric heating tape. The anode inlet temperature of the electrolyzer and the inlet target temperature value are input into the second PID controller to adjust the opening of the electric heating tape. This is the second-stage heating. The two-stage heating makes the deviation between the anode inlet temperature of the electrolyzer and the first target temperature within the preset deviation range.

[0015] Further, the rate of pulsed makeup water should be lower than the rate of pulsed drainage, and the time for opening the makeup water pneumatic control valve within a specified time should be lower than the time for opening the drainage pneumatic control valve.

[0016] The present invention also provides a device for dynamically adjusting the conductivity of a PEM electrolyzer test system. Applying the method described above, the device includes an electrolyzer, a pure water tank, a makeup water pump, a makeup water pneumatic control valve, a separator, a deionized resin tank, a circulation pump, a heater, a drainage pneumatic control valve, a back pressure valve, and a waste water tank. High-purity deionized water is supplied from the outside to the pure water tank. The pure water tank, the makeup water pump, the makeup water pneumatic control valve, and the inlet of the separator are connected in sequence through pipelines. The outlet of the separator, the deionized resin tank, the drainage pneumatic control valve, and the waste water tank are connected in sequence through pipelines. The pipeline between the deionized resin tank and the drainage pneumatic control valve is connected to the inlet of the circulation pump. The outlet of the circulation pump, the heater, and the anode inlet of the electrolyzer are connected through pipelines. The anode outlet of the electrolyzer is connected to the circulating water inlet of the separator through a pipeline. A back pressure valve is provided at the gas outlet of the separator.

[0017] Furthermore, the device further includes a heater outlet temperature sensor, a conductivity sensor, a circulating water flowmeter, and an electrolyzer anode inlet temperature sensor. The heater outlet temperature sensor is arranged on the pipeline at the outlet of the heater. The conductivity sensor and the circulating water flowmeter are arranged on the pipeline between the heater and the electrolyzer. The electrolyzer anode inlet temperature sensor is arranged at the anode inlet of the electrolyzer.

[0018] Furthermore, the device further includes an electric heating tape, which is wound around the pipeline between the anode inlet of the electrolyzer and the circulating water flowmeter.

[0019] Furthermore, the device further includes a differential pressure liquid level gauge, which is arranged inside the separator.

[0020] Furthermore, the device further includes a pressure sensor, which is arranged inside the separator and feeds back the pressure to the back pressure valve.

[0021] The advantages of the present invention are as follows:

[0022] (1) During the operation of the electrolyzer, the present invention adopts an online water replacement method to discharge the water with impurity ions in the circulating pipeline, and at the same time replenish the water of the pure water machine into the circulating water pipeline, so as to achieve the effect of reducing the conductivity. There is no need to stop the machine for treatment, nor to relieve pressure and cool down. After replacing the resin, replenish water, raise the temperature, and set the back pressure, reducing the time cost and the power generation cost.

[0023] (2) On the one hand, in the present invention, since the replenished water is at room temperature while the circulating water during operation is at high temperature, inevitably, during the water replenishment process, the temperature at the anode inlet of the electrolyzer will fluctuate and decrease, thus affecting the performance of the electrolyzer. Therefore, the present invention proposes a pulse water replenishment method, and through secondary temperature control, the temperature at the anode inlet of the electrolyzer is stabilized within a preset temperature range, reducing the impact of temperature fluctuations on the performance of the electrolyzer. On the other hand, during the high-pressure endurance operation process, the replenishment and drainage of water will also cause significant fluctuations in the anode pressure. Therefore, the present invention also proposes a pulse drainage method to stabilize the pressure fluctuations within the accuracy range, thereby reducing the impact of large pressure fluctuations on the performance of the electrolyzer.

[0024] (3) The rate of pulse water replenishment in the present invention is lower than the rate of pulse drainage, that is, the time for opening the water replenishment pneumatic control valve within a specified time is lower than the time for the drainage pneumatic control valve; by setting the pulse replenishment and drainage time, a small amount of water in the separator can be discharged and replenished, further stabilizing the temperature fluctuations during the operation of the electrolyzer; to ensure the pressure stability during the operation of the electrolyzer under a wide range of pressures, the pulse drainage time can be set at different pressures.

[0025] (4) Through the two-stage heating method in the present invention, the temperature at the anode inlet of the electrolyzer can always maintain a very small deviation from the target value, so that the electrolyzer always maintains a stable temperature operation state. By setting the opening time of the pulse water replenishment and drainage pneumatic control valves, and the start of the water replenishment and drainage pneumatic control valves limited by pressure and temperature, during the constant pressure and constant temperature operation of the electrolyzer, the conductivity of the circulating water can be dynamically adjusted while controlling the temperature at the anode inlet of the electrolyzer and the pressure of the anode system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of a device for dynamically adjusting the conductivity of a PEM electrolyzer test system disclosed in an embodiment of the present invention;

[0027] Figure 2 It is a flowchart of a method for dynamically adjusting the conductivity of a PEM electrolyzer test system disclosed in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0029] Embodiment 1

[0030] AsFigure 1 As shown in the figure, the device for dynamically adjusting the conductivity of a PEM electrolyzer 1 test system provided by Embodiment 1 of the present invention includes an electrolyzer 1, a pure water tank 2, a makeup water pump 3, a makeup water pneumatic control valve 4, a separator 5, a deionized resin tank 6, a circulation water pump 7, a heater 8, a heater outlet temperature sensor 9, a drainage pneumatic control valve 10, a conductivity sensor 11, a circulating water flowmeter 12, an electric heating tape 13, an electrolyzer anode inlet temperature sensor 14, a differential pressure liquid level gauge 15, a pressure sensor 16, a back pressure valve 17, and a waste water tank 18. It integrates an electrolyte circulation module, an oxygen pressure control module, and a pure water supply module. The electrolyte circulation module is the above-mentioned separator 5, differential pressure liquid level gauge 15, deionized resin tank 6, circulation water pump 7, heater 8, heater outlet temperature sensor 9, drainage pneumatic control valve 10, conductivity sensor 11, circulating water flowmeter 12, electric heating tape 13, electrolyzer anode inlet temperature sensor 14, and electrolyzer 1. The oxygen pressure control module is the above-mentioned pressure sensor 16 and back pressure valve 17, and the pure water supply module is the above-mentioned pure water tank 2, makeup water pump 3, and makeup water pneumatic control valve 4. The pure water supply module mainly supplies high-purity deionized water to the entire system, and the electrolyte circulation module mainly provides electrolyte for the electrolyzer 1, mainly including anode electrolyte circulation; the anode electrolyte circulation mainly circulates the electrolyte flowing out of the anode separator 5 through a circulation pump for anode electrolyte circulation; the oxygen pressure control module mainly produces oxygen from the anode outlet during the operation of the electrolyzer 1 and entrains the electrolyte, enters the anode separator 5 for dehydration, then adjusts the anode side pressure through the back pressure valve 17, and finally vents the oxygen.

[0031] High-purity deionized water is externally supplied to the pure water tank 2. The pure water tank 2, makeup water pump 3, makeup water pneumatic control valve 4, and the inlet of the separator 5 are sequentially connected through pipelines. The high-purity deionized water in the pure water tank 2 is replenished into the circulating water system through the makeup water pump 3 and the makeup water pneumatic control valve 4. The outlet of the separator 5, deionized resin tank 6, drainage pneumatic control valve 10, and waste water tank 18 are sequentially connected through pipelines. The pipeline between the deionized resin tank 6 and the drainage pneumatic control valve 10 is connected to the inlet of the circulation water pump 7, that is, the deionized resin tank 6, drainage pneumatic control valve 10, and circulation water pump 7 are connected through a tee. The outlet of the circulation water pump 7, heater 8, and the anode inlet of the electrolyzer 1 are connected through pipelines. The anode outlet of the electrolyzer 1 is connected to the circulating water inlet of the separator 5 through a pipeline, and a back pressure valve 17 is provided at the gas outlet of the separator 5.

[0032] ​The heater outlet temperature sensor 9 is arranged on the pipeline at the outlet of the heater 8, the conductivity sensor 11 and the circulating water flowmeter 12 are arranged on the pipeline between the heater 8 and the electrolytic cell 1, and the electrolytic cell anode inlet temperature sensor 14 is arranged at the anode inlet of the electrolytic cell 1. The electric heating tape 13 is wound around the pipeline between the anode inlet of the electrolytic cell 1 and the circulating water flowmeter 12. The differential pressure liquid level gauge 15 is inserted at the top of the separator 5. The pressure sensor 16 is arranged inside the separator 5 and feeds back the pressure to the back pressure valve 17. The back pressure valve 17 adjusts the opening degree of the back pressure valve 17 through the feedback value of the pressure sensor 16 to achieve the effect of stabilizing the pressure.

[0033] Embodiment 2

[0034] As Figure 2 shown, based on the device of Embodiment 1, Embodiment 2 of the present invention provides a method for dynamically adjusting the conductivity of a PEM electrolytic cell 1 test system. The method includes:

[0035] Set the water replenishment and drainage target liquid levels according to the differential pressure liquid level gauge 15. When the water replenishment target liquid level is reached, the water replenishment pump 3 and the water replenishment pneumatic control valve 4 are closed. When the drainage target liquid level is reached, the drainage pneumatic control valve 10 is closed. Set the high conductivity target value, the low conductivity target value, the pulsed drainage time, the pulsed water replenishment time, the set waiting time, the set pressure target value, and the set anode inlet temperature target value.

[0036] During the constant pressure and constant temperature operation of the electrolytic cell 1, when the feedback value of the conductivity sensor 11 in the PEM electrolytic cell 1 test system is higher than the first set value, the water replenishment and drainage script, that is, the water replenishment and drainage program, is triggered. The water replenishment pump 3 is opened, and the water replenishment pneumatic control valve 4 and the drainage pneumatic control valve 10 are pulsed open. Water replenishment and drainage are carried out simultaneously until the feedback value of the conductivity sensor 11 is lower than the second set value, and then the water replenishment and drainage program is stopped, and the water replenishment pump 3, the water replenishment pneumatic control valve 4, and the drainage pneumatic control valve 10 are closed.

[0037] According to the feedback of the pressure sensor 16, if the feedback value of the pressure sensor 16 detected in the PEM electrolytic cell 1 test system during the water replenishment and drainage process is within the set range of the pressure limit value, the water replenishment pump 3, the water replenishment pneumatic control valve 4, and the drainage pneumatic control valve 10 are closed. When it is detected that the pipeline pressure differs from the target value within the preset range, the water replenishment pump 3, the water replenishment pneumatic control valve 4, and the drainage pneumatic control valve 10 are triggered to open again. In practical applications, the set range of the pressure limit value is not particularly limited and can be adjusted according to actual needs. For example, it can be set to 99 kPa to 101 kPa. The target value of the pipeline pressure is not particularly limited and can be adjusted according to actual needs. For example, it can be set to 80 kPa. The preset range can be 1 to 2 kPa, that is, when the pipeline pressure differs from the target value by 1 to 2 kPa, the water replenishment pump 3, the water replenishment pneumatic control valve 4, and the drainage pneumatic control valve 10 are triggered to open again.

[0038] When the feedback value of the electrolytic cell anode inlet temperature sensor 14 of the PEM electrolytic cell 1 test system is less than the first target temperature, the makeup water pump 3, the makeup water pneumatic control valve 4, and the drain pneumatic control valve 10 need to be closed. When the feedback value of the electrolytic cell anode inlet temperature sensor 14 is greater than the second target temperature, continue to trigger the opening of the makeup water pump 3, the makeup water pneumatic control valve 4, and the drain pneumatic control valve 10. In practical applications, the value of the first target temperature is not particularly limited and can be adjusted according to actual needs, and the value range can be 79°C to 79.4°C. The value of the second target temperature is not particularly limited and can be adjusted according to actual needs, and the value range can be 79.8°C to 80.2°C. The second target temperature is greater than the first target temperature, and the second target temperature is closer to the set electrolytic cell anode inlet temperature. The makeup and drain script runs repeatedly and is limited by the pressure and temperature fluctuation ranges. During the constant pressure and constant temperature operation of the electrolytic cell 1, the makeup and drain script is triggered multiple times in small amounts until the conductivity is reduced to the target conductivity, and then the makeup water pneumatic control valve 4 and the makeup water pump 3 are pulsed to fill the separator 5 liquid level to the target level and stop. Among them, the rate of pulsed makeup water should be lower than the rate of pulsed drainage, that is, the time to open the makeup water pneumatic control valve 4 within a specified time should be lower than the time of the drain pneumatic control valve 10; by setting the pulsed makeup and drain time, a small amount of water in the separator 5 can be discharged and replenished, further stabilizing the temperature fluctuation during the operation of the electrolytic cell 1; to ensure the pressure stability during the operation of the electrolytic cell 1 under a wide range of pressures, it is necessary to set the pulsed drainage time at different pressures.

[0039] The anode inlet temperature of the electrolytic cell 1 can quickly raise the temperature of the replenished deionized water to the target temperature through a two-stage temperature control method. The specific process is as follows: When water is replenished into the separator 5, the temperature of the deionized water in the separator 5 decreases. Since the entire circulating water system is in a circulating heating state, that is, the water is circulated by the circulating water pump 7 to the heater 8, the value feedback by the outlet temperature sensor 9 of the heater and the outlet target temperature value are input into the first PID controller and the opening of the heater 8 is adjusted so that the water replenished into the separator 5 can be quickly heated up. This is the first-stage heating. The control principle of the first PID controller is prior art. It calculates the deviation between the value feedback by the outlet temperature sensor 9 of the heater and the outlet target temperature value, and continuously adjusts the opening of the heater 8, so that the value feedback by the outlet temperature sensor 9 of the heater is consistent with the outlet target temperature value. Since there is a certain distance of pipeline from the heater 8 to the anode inlet of the electrolytic cell 1 and there is heat dissipation, the pipeline between the anode inlet of the electrolytic cell 1 and the outlet of the circulating water flowmeter 12 is wound with an electric heating tape to further compensate the dissipated temperature by the electric heating tape. The anode inlet temperature of the electrolytic cell 1 and the inlet target temperature value are input into the second PID controller and the opening of the electric heating tape is adjusted. The opening of the electric heating tape is also the output power of the electric heating tape. This is the second-stage heating. The two-stage heating makes the deviation between the anode inlet temperature of the electrolytic cell 1 and the first target temperature within the preset deviation range, so as to keep the electrolytic cell 1 in a stable operating state with a constant temperature. The control principle of the second PID controller is prior art. It calculates the deviation between the anode inlet temperature of the electrolytic cell 1 and the inlet target temperature value, and adjusts the opening of the electric heating tape so that the anode inlet temperature of the electrolytic cell 1 is consistent with the inlet target temperature value.

[0040] In summary, during the process of providing a test environment load for the electrolytic cell 1 in the prior art PEM electrolytic cell 1 test system, during the endurance test, since the catalytic layer will fall off during the continuous electrolysis process of the electrolytic cell 1, the resin needs to be replaced when it reaches the end of its life. Otherwise, it will cause an increase in the conductivity of the circulating water, reduce the performance of the electrolytic cell 1, and require shutdown for treatment, replacement of deionized resin, which delays the test progress. Based on this, the method and device of the present invention for automatically supplementing and draining water to reduce the conductivity in the circulating water system while reducing temperature and pressure fluctuations can effectively avoid the time and cost of disassembling and replacing deionized resin and shutdown, cooling, pressure relief, startup, heating, and pressure boosting. Controlling the conductivity within a suitable range is crucial for ensuring the stability, hydrogen production, and efficiency of the PEM electrolysis system. Optimizing the electrolyte composition, controlling the electrolyte concentration, and current density are all key measures to improve the system performance and extend the equipment life.

[0041] The method of online water replacement during the operation of the electrolyzer 1 proposed by the present invention discharges the water with impurity ions in the circulation pipeline, and at the same time replenishes the water from the pure water machine into the circulation water pipeline to achieve the effect of reducing the conductivity. On the one hand, since the replenished water is at room temperature while the circulating water during operation is at high temperature, inevitably during the water replenishment process, the temperature at the anode inlet of the electrolyzer 1 will fluctuate and decrease, thus affecting the performance of the electrolyzer 1. Therefore, the present invention proposes a pulse water replenishment method, and through secondary temperature control, the temperature at the anode inlet of the electrolyzer 1 is stabilized within a preset range to reduce the impact of temperature fluctuations on the performance of the electrolyzer 1. On the other hand, during the high-voltage endurance operation process, the replenishment and drainage of water will also cause large fluctuations in the anode pressure. Therefore, the present invention also proposes a pulse drainage method to stabilize the pressure fluctuations within the accuracy range, thereby reducing the impact of large pressure fluctuations on the performance of the electrolyzer 1.

[0042] The present invention can realize that during the long-term low-conductivity operation of the electrolyzer 1, by limiting the opening time of the water replenishment and drainage pneumatic control valve 10 through temperature and pressure, the operating temperature and pressure of the electrolyzer 1 are always maintained around the target value, providing a stable operating environment for the electrolyzer 1 and not requiring shutdown for reducing conductivity during long-term operation; the present invention can realize the stability of the temperature at the anode inlet of the electrolyzer 1 and the system pressure during the long-term low-conductivity operation of the electrolyzer 1 within a wide pressure and wide temperature range.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for dynamically adjusting the conductivity of a PEM electrolyzer test system, characterized in that: Methods include: When the conductivity detected in the PEM electrolyzer test system is higher than the first set value, the water replenishment and drainage program is triggered, the water replenishment pump is turned on, and the water replenishment air-controlled valve and the drainage air-controlled valve are opened in a pulsed manner to replenish water and drain water at the same time until the detected conductivity is lower than the second set value, then the water replenishment and drainage program is stopped, and the water replenishment pump, the water replenishment air-controlled valve and the drainage air-controlled valve are closed.

2. The method for dynamically adjusting the conductivity of a PEM electrolyzer test system according to claim 1, characterized in that: The method further comprises: If the PEM electrolyzer test system detects that the pipeline pressure is within the set pressure limit during the replenishment and drainage process, the water replenishment pump, water replenishment air control valve and drainage air control valve will be closed. When it is detected that the difference between the pipeline pressure and the target value is within the preset range, the water replenishment pump, water replenishment air control valve and drainage air control valve will continue to be triggered to open.

3. The method for dynamically adjusting the conductivity of a PEM electrolyzer test system according to claim 1, characterized in that: The method further comprises: If the anode inlet temperature of the electrolyzer of the PEM electrolyzer test system is lower than the first target temperature, the water supply pump, the water supply gas control valve and the drainage gas control valve need to be closed. When the anode inlet temperature of the electrolyzer is higher than the second target temperature, the water supply pump, the water supply gas control valve and the drainage gas control valve continue to be triggered to open, wherein the second target temperature is higher than the first target temperature.

4. The method for dynamically adjusting the conductivity of a PEM electrolyzer test system according to claim 1, characterized in that: The anode inlet temperature of the electrolytic cell is raised to the first target temperature by a two-stage temperature control method. The specific process is: after the water is added to the separator, the temperature of the deionized water in the separator decreases, and the water is circulated to the heater by a circulating water pump. The outlet temperature of the heater and the outlet target temperature value are input into the first PID controller and the opening of the heater is adjusted to raise the temperature of the water added to the separator. This is a one-stage temperature control. Since there is a certain distance between the heater and the anode inlet of the electrolytic cell, there is heat dissipation. The pipeline at the anode inlet of the electrolytic cell is wrapped with an electric heating tape, and the anode inlet temperature of the electrolytic cell and the inlet target temperature value are input into the second PID controller and the opening of the electric heating tape is adjusted. This is a two-stage temperature increase. The two-stage temperature increase makes the deviation between the anode inlet temperature of the electrolytic cell and the first target temperature within a preset deviation range.

5. The method for dynamically adjusting the conductivity of a PEM electrolyzer test system according to claim 1, characterized in that: The pulse water replenishment rate must be lower than the pulse drainage rate, and the time for opening the water replenishment air control valve within the specified time must be lower than the time for opening the drainage air control valve.

6. A device for dynamically adjusting the conductivity of a PEM electrolyzer test system, characterized in that: The method described in any one of claims 1 to 5 is applied, wherein the device comprises an electrolytic cell, a pure water tank, a water replenishment pump, a water replenishment gas-controlled valve, a separator, a deionized resin tank, a circulating water pump, a heater, a drainage gas-controlled valve, a back-pressure valve and a waste water tank, and high-purity deionized water is supplied to the pure water tank from the outside. The pure water tank, the water replenishment pump, the water replenishment gas-controlled valve and the inlet of the separator are connected in sequence through a pipeline, the outlet of the separator, the deionized resin tank, the drainage gas-controlled valve and the waste water tank are connected in sequence through a pipeline, the pipeline between the deionized resin tank and the drainage gas-controlled valve is connected to the inlet of the circulating water pump, the outlet of the circulating water pump, the heater and the anode inlet of the electrolytic cell are connected through a pipeline, the anode outlet of the electrolytic cell is connected to the circulating water inlet of the separator through a pipeline, and a back-pressure valve is provided at the gas outlet of the separator.

7. The device for dynamically adjusting the conductivity of a PEM electrolyzer test system according to claim 6, characterized in that: It also includes a heater outlet temperature sensor, a conductivity sensor, a circulating water flow meter, and an electrolytic cell anode inlet temperature sensor. The heater outlet temperature sensor is arranged on the pipe at the heater outlet, the conductivity sensor and the circulating water flow meter are arranged on the pipe between the heater and the electrolytic cell, and the electrolytic cell anode inlet temperature sensor is arranged at the anode inlet of the electrolytic cell.

8. The device for dynamically adjusting conductivity of a PEM electrolyzer test system according to claim 7, characterized in that: It also includes an electric heating belt, which is wound on the pipeline between the anode inlet of the electrolytic cell and the circulating water flow meter.

9. The device for dynamically adjusting conductivity of a PEM electrolyzer test system according to claim 6, characterized in that: It also includes a differential pressure level gauge, which is arranged in the separator.

10. The device for dynamically adjusting conductivity of a PEM electrolyzer test system according to claim 6, characterized in that: A pressure sensor is also included, which is disposed in the separator and feeds back the pressure to the back pressure valve.

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