Multifunctional hydrogen production circulation system and its control method

Abstract

The present application discloses a multi-functional hydrogen production circulation system and its control method. The multi-functional hydrogen production circulation system includes a water replenishment circuit, a deionized water circulation circuit, and an electrolytic cell circulation circuit. By setting up the water replenishment circuit, the deionized water circulation circuit, and the electrolytic cell circulation circuit, the connection position of the deionized water circulation circuit and the electrolytic cell circulation circuit is before the oxygen-water primary separation tank, and is connected to the oxygen-water primary separation tank through an anti-turbulence mixing pipeline, which can effectively mix and avoid the turbulence phenomenon caused by different water temperatures in the deionized water circulation circuit and the electrolytic cell circulation circuit, and can effectively control the inlet water conductivity and stably control the pure water conductivity and temperature entering the electrolytic cell by using the water replenishment circuit and the deionized water circulation circuit.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogen production systems, and particularly relates to a multifunctional hydrogen production circulation system and a control method thereof. Background Art

[0002] There are many drawbacks in the current hydrogen production system: First, it is difficult to accurately control the conductivity of the inlet water, resulting in an out-of-control state; Second, for the conductivity and temperature of the pure water entering the electrolyzer, stable and effective control cannot be achieved, with frequent fluctuations, seriously affecting the hydrogen production efficiency and quality; Third, during the operation of the system, there is a huge energy loss, a large amount of energy is wasted without reason and not reasonably utilized; Fourth, from the perspective of cost-benefit, the economy is poor, the input-output ratio is low, which is not conducive to long-term operation and market promotion; Fifth, in terms of safety, the potential risk coefficient is quite high, there are hidden dangers in many links, posing a greater threat to personnel, equipment and the surrounding environment. Summary of the Invention

[0003] Embodiments of the present application provide a multifunctional hydrogen production circulation system and a control method thereof, which can solve the technical problems of the existing hydrogen production system that cannot effectively control the conductivity of the inlet water, cannot stably control the conductivity and temperature of the pure water entering the electrolyzer, has serious energy waste, poor economy, and high safety risk coefficient.

[0004] Embodiments of the present application provide a multifunctional hydrogen production circulation system, including a water replenishment circuit, a deionized water circulation circuit and an electrolyzer circulation circuit;

[0005] The deionized water circulation circuit is a ring-connected deionized water circulation pump, heat exchanger, deionizer, electric heater, oxygen-water primary separation tank, and the deionized water circulation pump;

[0006] The electrolyzer circulation circuit is a ring-connected electrolyzer circulation pump, PEM electrolyzer, the oxygen-water primary separation tank, and the electrolyzer circulation pump;

[0007] The access point of the water replenishment circuit is located between the heat exchanger and the deionized water circulation pump;

[0008] Wherein the output end of the electric heater and the anode water outlet of the PEM electrolyzer converge into one path and are connected to the oxygen-water primary separation tank through an anti-turbulence mixing pipeline.

[0009] Further, the water replenishment circuit includes a pure water tank and a water replenishment pump. The pure water tank is provided with a deionized water input pipeline, and the pure water tank is connected to the position between the heat exchanger and the deionized water circulation pump through the water replenishment pump.

[0010] Further, the cathode water outlet of the PEM electrolyzer is connected to the pure water tank through a hydrogen primary separation tank.

[0011] The present application also provides a control method for a multifunctional hydrogen production circulation system, which includes:

[0012] When the multifunctional hydrogen production circulation system is in an operating state, obtain the conductivity of the primary oxygen-water separation tank, and determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to a first threshold S1;

[0013] When the conductivity of the primary oxygen-water separation tank is less than the first threshold S1, start the electrolytic cell circulation loop;

[0014] When the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold S1, after setting a first delay duration, determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to a second threshold S2, where the second threshold S2 is greater than the first threshold S1;

[0015] When the conductivity of the primary oxygen-water separation tank is greater than or equal to the second threshold S2, close the electrolytic cell circulation loop, and continue to determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold S1;

[0016] When the conductivity of the primary oxygen-water separation tank is less than the second threshold S2, then determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to a third threshold S3, where the third threshold S3 is greater than the second threshold S2;

[0017] When the conductivity of the primary oxygen-water separation tank is greater than the third threshold S3, after setting a second delay duration, close the multifunctional hydrogen production circulation system;

[0018] When the conductivity of the primary oxygen-water separation tank is less than or equal to the third threshold S3, set the deionized water circulation loop to operate at the maximum flow rate, and continue to determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold S1.

[0019] Furthermore, the control method for the multifunctional hydrogen production circulation system further includes:

[0020] Determine whether the first delay duration has ended. If not, continue to determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold S1. If so, determine whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the second threshold S2;

[0021] Determine whether the second delay duration has ended. If so, close the multifunctional hydrogen production circulation system. If not, continue to determine whether the conductivity of the primary oxygen-water separation tank is greater than the third threshold S3.

[0022] Furthermore, the control method for the multifunctional hydrogen production circulation system further includes:

[0023] When the conductivity of the primary oxygenated water separation tank is less than the first threshold S1, set the deionized water circulation loop to calculate the amount of circulating water passing through the deionizer according to the flow limits of the deionized water circulation pump and the electrolytic cell circulation pump;

[0024] When the conductivity of the primary oxygenated water separation tank is greater than or equal to the first threshold S1, by calculate a delay of the first duration t, where Q is the amount of circulating water passing through the deionizer, V is the water storage capacity of the system, is the deionizer efficiency, and C(t) is the conductivity of the primary oxygenated water separation tank at different times.

[0025] Further, the control method of the multifunctional hydrogen production circulation system further includes:

[0026] When the multifunctional hydrogen production circulation system is in an operating state, obtain the real-time temperature value T1 of the primary oxygenated water separation tank, obtain the real-time temperature value T2 at the output end of the heat exchanger, obtain the set key temperature threshold T3 of the key regulating valve of the heat exchanger, and determine whether the real-time temperature value T1 of the heat exchanger is greater than the set key temperature threshold T3 of the key regulating valve of the heat exchanger;

[0027] When the real-time temperature value T1 of the heat exchanger is greater than the set key temperature threshold T3 of the key regulating valve of the heat exchanger, turn off the electric heater;

[0028] When the real-time temperature value T1 of the heat exchanger is less than or equal to the set key temperature threshold T3 of the key regulating valve of the heat exchanger, determine whether there is flow in the deionized water circulation loop;

[0029] If there is no flow in the deionized water circulation loop, set a delay of the third duration and then turn off the multifunctional hydrogen production circulation system. If there is flow in the deionized water circulation loop, turn on the electric heater and adjust the real-time temperature value T1 of the heat exchanger to the set key temperature threshold T3 of the key regulating valve of the heat exchanger.

[0030] Further, when the real-time temperature value T1 of the heat exchanger is greater than the set key temperature threshold T3 of the key regulating valve of the heat exchanger, after turning off the electric heater, it further includes:

[0031] Obtain the heat production Qnet of the PEM electrolytic cell and the heat exchange amount Qexc of the deionized water circulation loop;

[0032] When the heat generation quantity Qnet of the PEM electrolyzer is greater than the heat exchange quantity Qexc of the deionized water circulation loop, set the real-time temperature value T2 at the output end of the heat exchanger as the set temperature threshold T4, where the set temperature threshold T4 is greater than the set key temperature threshold T3; according to the real-time temperature value T1 of the heat exchanger and the set temperature threshold T4, adjust the opening degree of the key regulating valve of the heat exchanger through a proportional-integral-derivative algorithm;

[0033] When the heat generation quantity Qnet of the PEM electrolyzer is less than the heat exchange quantity Qexc of the deionized water circulation loop, adjust the opening degree of the key regulating valve of the heat exchanger through a proportional-integral-derivative algorithm according to the real-time temperature value T1 of the heat exchanger and the set key temperature threshold T3.

[0034] Further, obtaining the heat generation quantity of the PEM electrolyzer and the heat exchange quantity Qexc of the deionized water circulation loop includes:

[0035] By calculating the heat generation quantity of the PEM electrolyzer, where Istack is the total current of the PEM electrolyzer, Acell is the reaction area of the PEM electrolyzer, Ncell is the number of electrolytic cell sections of the PEM electrolyzer, Vcell is the voltage of the PEM electrolyzer, and Vth is the electrolytic voltage of the PEM electrolyzer;

[0036] By calculating the heat dissipation quantity of the PEM electrolyzer, where h is the heat conduction coefficient, Tstack is the stack temperature, and Tamb is the ambient temperature;

[0037] By calculating the heat generation quantity Qnet of the PEM electrolyzer;

[0038] By calculating the heat exchange quantity Qexc of the deionized water circulation loop, where C is the specific heat capacity of water, m is the mass of water, and Δt is the temperature difference.

[0039] Further, adjusting the opening degree of the key regulating valve of the heat exchanger through a proportional-integral-derivative algorithm includes:

[0040] The proportional-integral-derivative algorithm is ; where Kp, Ki, and Kd are the proportional gain coefficient, integral gain coefficient, and derivative gain coefficient respectively, and e(t) is the deviation between the set temperature and the actual temperature.

[0041] Further, the control method of the multifunctional hydrogen production circulation system further includes:

[0042] When the multi-functional hydrogen production circulation system is in an operating state, obtain the flow rate of the PEM electrolyzer and the flow rate of the deionized water circulation loop, and calculate the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer;

[0043] Obtain the relationship between the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer and the temperature of the deionized water circulation loop, and adjust the temperature of the deionized water circulation loop based on the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer.

[0044] The multi-functional hydrogen production circulation system and its control method provided by the embodiments of the present application, by setting up a water replenishment loop, a deionized water circulation loop and an electrolyzer circulation loop, the connection positions of the deionized water circulation loop and the electrolyzer circulation loop are before the oxygen-water primary separation tank, and are connected to the oxygen-water primary separation tank through an anti-turbulence mixing pipeline, which can effectively mix and avoid the turbulence phenomenon caused by different water temperatures of the deionized water circulation loop and the electrolyzer circulation loop, and can effectively control the inlet water conductivity and stably control the pure water conductivity and temperature entering the electrolyzer by using the water replenishment loop and the deionized water circulation loop. Description of the Drawings

[0045] The following will clearly and completely describe the technical solutions of the present application in conjunction with the specific embodiments of the present application with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0046] Figure 1 is a schematic structural diagram of the multi-functional hydrogen production circulation system provided by the embodiments of the present application;

[0047] Figure 2 is a flowchart of the control method of the multi-functional hydrogen production circulation system provided by the embodiments of the present application;

[0048] Figure 3 is a flowchart of the temperature adjustment of the deionized water circulation loop of the control method of the multi-functional hydrogen production circulation system provided by the embodiments of the present application. Detailed Embodiments

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0050] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a connection that enables mutual communication; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0051] Specifically, please refer to Figure 1 , the embodiment of the present application provides a multifunctional hydrogen production circulation system, including a water replenishment circuit, a deionized water circulation circuit, and an electrolytic cell circulation circuit;

[0052] The deionized water circulation circuit is a deionized water circulation pump P-0102, a heat exchanger E-0101, a deionizer X-0101, an electric heater H-0101, an oxygenated water primary separation tank V-0102, and the deionized water circulation pump P-0102 that are connected in a ring;

[0053] The electrolytic cell circulation circuit is an electrolytic cell circulation pump P-0103, a PEM electrolytic cell PK-0201, the oxygenated water primary separation tank V-0102, and the electrolytic cell circulation pump P-0103 that are connected in a ring;

[0054] The access point of the water replenishment circuit is located between the heat exchanger E-0101 and the deionized water circulation pump P-0102;

[0055] Among them, the output end of the electric heater H-0101 and the anode water outlet of the PEM electrolytic cell PK-0201 converge into one path and are connected to the oxygenated water primary separation tank V-0102 through an anti-turbulence mixing pipeline.

[0056] Among them, the deionized water replenishment temperature of the deionized water circulation circuit is usually lower than the water temperature at the anode water outlet of the PEM electrolytic cell PK-0201. Connecting the water replenishment point before the heat exchanger E-0101 can reduce the heat exchange amount of the heat exchanger E-0101, thereby reducing the volume and the system energy consumption.

[0057] Due to various uncertain factors, long-term storage, or the material of the storage medium not meeting the requirements of the deionized water source of the water replenishment circuit, the conductivity does not match the expectation. Connecting the deionized water before the deionizer X-0101 of the deionized water circulation circuit can immediately purify this part of the water, thereby avoiding polluting the system water quality and disturbing the system conductivity after entering the system.

[0058] The deionized water circulation pump P-0102 can increase the flow rate only when the conductivity is abnormal and operate at a low load under normal conditions, thereby reducing the system energy consumption. By adjusting the temperature in the oxygen water primary separation tank V-0102 instead of the electrolyzer temperature, the temperature change of the system is smoother, reducing the impact of temperature fluctuations on water quality control.

[0059] Among them, the deionized water circulation loop and the electrolyzer circulation loop are completely independent, avoiding the mutual influence of temperature and water quality fluctuations, and making the operating environment of the electrolyzer more stable.

[0060] Integrating the heater and the heat exchanger into the deionized water circulation loop, in the initial operation state (when the conductivity and temperature are unqualified), it does not enter the PEM electrolyzer PK-0201. The two loops are independent of each other and do not interfere with each other, which not only protects the PEM electrolyzer PK-0201 but also makes the control more stable; because the flow rate of the deionized water loop is lower, the volumes of the electric heater H-0101 and the heat exchanger E-0101 can be made smaller, facilitating system integration and making the multifunctional hydrogen production circulation system more concise and flexible.

[0061] Connected to the oxygen water primary separation tank V-0102 through an anti-turbulence mixing pipeline, it can effectively mix to avoid the turbulence phenomenon caused by different water temperatures in the deionized water circulation loop and the electrolyzer circulation loop, and improve the uniformity of the return water temperature.

[0062] Furthermore, the makeup water loop includes a pure water tank V-0101 and a makeup water pump P-0101. The pure water tank V-0101 is provided with a deionized water input pipeline, and the pure water tank V-0101 is connected to between the heat exchanger E-0101 and the deionized water circulation pump P-0102 through the makeup water pump P-0101.

[0063] By setting the pure water tank V-0101, it provides a short-term water source guarantee for the system, and does not affect the system operation when the external water source is interrupted, ensuring the stable operation of the PEM electrolyzer PK-0201.

[0064] Furthermore, the cathode water outlet of the PEM electrolyzer PK-0201 is connected to the pure water tank V-0101 through a hydrogen primary separation tank.

[0065] This application recovers the deionized high-temperature water that has passed from the anode of the PEM electrolyzer PK-0201 due to concentration difference, pressure difference, and electroosmotic drag, saving the water consumption of the system; because the recovered is the high-temperature water flowing out of the PEM electrolyzer PK-0201, it efficiently utilizes the waste heat of the PEM electrolyzer PK-0201, reducing the additional heating demand, thereby reducing the operating energy consumption of the system; by intelligently adjusting the working states of the electric heater H-0101 and the heat exchanger E-0101, it reduces the energy consumption at non-high load, optimizing the energy consumption of the entire system.

[0066] Please refer to Figure 2 , this application also provides a control method for a multi-functional hydrogen production circulation system, which includes:

[0067] When the multi-functional hydrogen production circulation system is in an operating state, obtain the conductivity of the oxygenated water primary liquid separation tank V-0102, and determine whether the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to a first threshold S1;

[0068] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is less than the first threshold S1, start the electrolytic cell circulation loop;

[0069] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to the first threshold S1, set a first delay time and then determine whether the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to a second threshold S2, where the second threshold S2 is greater than the first threshold S1;

[0070] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to the second threshold S2, close the electrolytic cell circulation loop and continue to determine whether the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to the first threshold S1;

[0071] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is less than the second threshold S2, then determine whether the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to a third threshold S3, where the third threshold S3 is greater than the second threshold S2;

[0072] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than the third threshold S3, set a second delay time and then shut down the multi-functional hydrogen production circulation system;

[0073] When the conductivity of the oxygenated water primary liquid separation tank V-0102 is less than or equal to the third threshold S3, set the deionized water circulation loop to operate at the maximum flow rate and continue to determine whether the conductivity of the oxygenated water primary liquid separation tank V-0102 is greater than or equal to the first threshold S1.

[0074] In this embodiment, conductivity sensors are arranged at both the inlet (AT-0101) and outlet (AT-0102) of the circulating water. By collecting the real-time conductivity data C1 and C2 and comparing them with the set values S0 (0.055 μS / cm), S1 (0.2 μS / cm), set value S2 (0.2 - 0.9 μS / cm), and set value S3 (0.9 μS / cm), water quality adjustment and fault warning are achieved. Level sensors (LT-0101 / 0102) are arranged on the pure water storage tank and the primary oxygen-water separation tank. The real-time water volume data V1 is collected and involved in the system's calculation and judgment. Flow sensors FT0101 / 0102 are arranged on the double circulation loop. By collecting the real-time water flow rates Q1 and Q2, the power of the pump is changed to achieve the function of adjusting the water volume.

[0075] Further, the control method of the multifunctional hydrogen production circulation system further includes:

[0076] Judge whether the first delay duration has ended. If not, continue to judge whether the conductivity of the primary oxygen-water separation tank V-0102 is greater than or equal to the first threshold S1. If so, judge whether the conductivity of the primary oxygen-water separation tank V-0102 is greater than or equal to the second threshold S2.

[0077] Judge whether the second delay duration has ended. If so, turn off the multifunctional hydrogen production circulation system. If not, continue to judge whether the conductivity of the primary oxygen-water separation tank V-0102 is greater than the third threshold S3.

[0078] Further, the control method of the multifunctional hydrogen production circulation system further includes:

[0079] When the conductivity of the primary oxygen-water separation tank V-0102 is less than the first threshold S1, set the deionized water circulation loop to calculate the circulating water volume passing through the deionizer X-0101 according to the flow rate limits of the deionized water circulation pump P-0102 and the electrolytic cell circulation pump P-0103.

[0080] When the conductivity of the primary oxygen-water separation tank V-0102 is greater than or equal to the first threshold S1, through Calculate the first delay duration t, where Q is the circulating water volume passing through the deionizer X-0101 (t / h), V is the water storage volume of the system (m³), is the deionizer efficiency (%), and C(t) is the conductivity of the primary oxygen-water separation tank V-0102 at different times (μS / cm).

[0081] Please refer to Figure 3 , the control method of the multifunctional hydrogen production circulation system further includes:

[0082] When the multi-functional hydrogen production circulation system is in operation, obtain the real-time temperature value T1 of the oxygen-water primary separation tank V-0102, obtain the real-time temperature value T2 at the output end of the heat exchanger E-0101, obtain the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101, and determine whether the real-time temperature value T1 of the heat exchanger E-0101 is greater than the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101;

[0083] When the real-time temperature value T1 of the heat exchanger E-0101 is greater than the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101, turn off the electric heater H-0101;

[0084] When the real-time temperature value T1 of the heat exchanger E-0101 is less than or equal to the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101, determine whether there is flow in the deionized water circulation loop;

[0085] If there is no flow in the deionized water circulation loop, set a third delay time and then turn off the multi-functional hydrogen production circulation system. If there is flow in the deionized water circulation loop, turn on the electric heater H-0101 and adjust the real-time temperature value T1 of the heat exchanger E-0101 to the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101.

[0086] Further, when the real-time temperature value T1 of the heat exchanger E-0101 is greater than the set key temperature threshold T3 of the key regulating valve TV-0501 of the heat exchanger E-0101, after turning off the electric heater H-0101, it further includes:

[0087] Obtain the heat production Qnet of the PEM electrolyzer PK-0201 and the heat exchange Qexc of the deionized water circulation loop;

[0088] When the heat production Qnet of the PEM electrolyzer PK-0201 is greater than the heat exchange Qexc of the deionized water circulation loop, set the real-time temperature value T2 at the output end of the heat exchanger E-0101 to the set temperature threshold T4, where the set temperature threshold T4 is greater than the set key temperature threshold T3; according to the real-time temperature value T1 of the heat exchanger E-0101 and the set temperature threshold T4, adjust the opening of the key regulating valve TV-0501 of the heat exchanger E-0101 through a proportional-integral-derivative algorithm;

[0089] When the heat generation quantity Qnet of the PEM electrolyzer PK-0201 is less than the heat exchange quantity Qexc of the deionized water circulation loop, the opening degree of the key regulating valve TV-0501 of the heat exchanger E-0101 is adjusted by a proportional-integral-derivative algorithm according to the real-time temperature value T1 of the heat exchanger E-0101 and the set key temperature threshold T3.

[0090] Further, obtaining the heat generation quantity of the PEM electrolyzer PK-0201 and the heat exchange quantity Qexc of the deionized water circulation loop includes:

[0091] By calculating the heat generation quantity of the PEM electrolyzer PK-0201, where Istack is the total current (A) of the PEM electrolyzer PK-0201, Acell is the reaction area (cm 2 ) of the PEM electrolyzer PK-0201, Ncell is the number of electrolytic cell sections (pieces) of the PEM electrolyzer PK-0201, Vcell is the voltage (V) of the PEM electrolyzer PK-0201, and Vth is the electrolytic voltage (1.48 V) of the PEM electrolyzer PK-0201;

[0092] By calculating the heat dissipation quantity of the PEM electrolyzer PK-0201, where h is the heat transfer coefficient (the thermal conductivity of the material, unit: W / m·K), Tstack is the stack temperature (the operating temperature of the electrolyzer, unit: °C), and Tamb is the ambient temperature (the external air temperature, unit: °C);

[0093] By calculating the heat generation quantity Qnet of the PEM electrolyzer PK-0201;

[0094] By calculating the heat exchange quantity Qexc of the deionized water circulation loop, where C is the specific heat capacity of water (J / (kg·°C)), m is the mass of water (kg), and Δt is the temperature difference (°C).

[0095] Further, adjusting the opening degree of the key regulating valve TV-0501 of the heat exchanger E-0101 by a proportional-integral-derivative algorithm includes:

[0096] The proportional-integral-derivative algorithm is ; where, Kp, Ki, and Kd are the proportional gain coefficient, integral gain coefficient, and derivative gain coefficient respectively, and e(t) is the deviation between the set temperature and the actual temperature; when the heat generation Qnet of the PEM electrolyzer PK-0201 is greater than the heat exchange amount Qexc of the deionized water circulation loop, e(t) = T4 - T2; when the heat generation Qnet of the PEM electrolyzer PK-0201 is less than the heat exchange amount Qexc of the deionized water circulation loop, e(t) = T3 - T2.

[0097] Further, the control method of the multifunctional hydrogen production circulation system further includes:

[0098] When the multifunctional hydrogen production circulation system is in an operating state, obtain the flow rate of the PEM electrolyzer PK-0201 and the flow rate of the deionized water circulation loop, and calculate the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer PK-0201;

[0099] Obtain the relationship between the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer PK-0201 and the temperature of the deionized water circulation loop, and adjust the temperature of the deionized water circulation loop based on the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer PK-0201.

[0100] Among them, the relationship between the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer PK-0201 and the temperature of the deionized water circulation loop is shown in Table 1.

[0101] Table 1 Relationship between the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolyzer PK-0201 and the temperature of the deionized water circulation loop

[0102] Serial number Flow rate ratio Temperature of deionized circulation loop 1 0.05 37.4812474 2 0.055 41.6407959 3 0.06 45.1024583 4 0.065 48.0156113 5 0.07 50.5088256 6 0.075 52.6666075 7 0.08 54.5381244 8 0.085 56.1916681 9 0.09 57.6599448 10 0.095 58.970302 11 0.1 60.1486066 12 0.105 61.212153 13 0.11 62.1775874 14 0.115 63.0590763 15 0.12 63.8653963 16 0.125 64.6068721 17 0.13 65.2903739 18 0.135 65.9229599 19 0.14 66.5094738 20 0.145 67.0552697 21 0.15 67.5644101 22 0.155 68.0402497 23 0.16 68.4861648 24 0.165 68.9047052 25 0.17 69.2985553 26 0.175 69.6694557 27 0.18 70.0197447 28 0.185 70.3508365 29 0.19 70.6643827 30 0.195 70.9617575 31 0.2 71.2441072 32 0.205 71.5125227 33 0.21 71.7682161 34 0.215 72.0118005 35 0.22 72.2442906 36 0.225 72.466348 37 0.23 72.6787005 38 0.235 72.8819244 39 0.24 73.0766687 40 0.245 73.263369 41 0.25 73.4425656 42 0.255 73.6146967 43 0.26 73.7801614 44 0.265 73.9393519 45 0.27 74.0925978 46 0.275 74.2402419 47 0.28 74.385451 48 0.285 74.521006 49 0.29 74.6535672 50 0.295 74.7816006 51 0.3 74.9053378

[0103] It can be seen from the above table that when the electrolyzer operates at full load, in order to ensure that the electrolyzer operates at the set temperature, the flow rate ratio of the deionized water path needs to meet the above table, and a suitable value is set within the ratio range for control.

[0104] Among them, the cooling capacity of the system is accurately adjusted by controlling the cold water side proportional valve, thereby controlling the temperature of the entire system; the temperature measurement point is installed inside the tank to make the control more stable and the fluctuation smaller; the conductivity measurement point is installed inside the tank to make the conductivity more stable and the fluctuation smaller; the system monitors the conductivity of the deionized water in real time, and through accurate measurement and compensation formula, ensures that the conductivity fluctuation is minimized and the water quality is stable during the operation of the electrolyzer; when the conductivity is abnormal, the flow rate of the deionized water circulation pump is automatically adjusted to respond quickly and avoid the system conductivity not meeting the standard and affecting the hydrogen production efficiency.

[0105] The multi-functional hydrogen production circulation system and its control method provided by the embodiments of the present application, by setting up a water replenishment circuit, a deionized water circulation circuit and an electrolytic cell circulation circuit, the connection position of the deionized water circulation circuit and the electrolytic cell circulation circuit is before the oxygen-water primary separation tank V-0102, and is connected to the oxygen-water primary separation tank V-0102 through an anti-turbulence mixing pipeline, which can effectively mix to avoid the turbulence phenomenon caused by different water temperatures of the deionized water circulation circuit and the electrolytic cell circulation circuit, and can effectively control the inlet water conductivity and stably control the pure water conductivity and temperature entering the electrolytic cell by using the water replenishment circuit and the deionized water circulation circuit.

[0106] In the above embodiments, the descriptions of the respective embodiments have their own focuses. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0107] The above has introduced in detail a multi-functional hydrogen production circulation system and its control method provided by the embodiments of the present application. Specific examples are used herein to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application; those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A control method for a multi-functional hydrogen production circulation system, characterized in that, The multifunctional hydrogen production circulation system includes a water replenishment circuit, a deionized water circulation circuit, and an electrolyzer circulation circuit; The deionized water circulation circuit is a ring-connected deionized water circulation pump, heat exchanger, deionizer, electric heater, oxygen-water primary separation tank, and the deionized water circulation pump; The electrolyzer circulation circuit is a ring-connected electrolyzer circulation pump, PEM electrolyzer, the oxygen-water primary separation tank, and the electrolyzer circulation pump; The access point of the water replenishment circuit is located between the heat exchanger and the deionized water circulation pump; Among them, the output end of the electric heater and the anodic water outlet of the PEM electrolyzer converge into one path and are connected to the oxygen-water primary separation tank through an anti-turbulence mixing pipeline; Among them, the control method of the multifunctional hydrogen production circulation system includes: When the multifunctional hydrogen production circulation system is in an operating state, obtain the conductivity of the oxygen-water primary separation tank, and judge whether the conductivity of the oxygen-water primary separation tank is greater than or equal to the first threshold value S1; When the conductivity of the oxygen-water primary separation tank is less than the first threshold value S1, start the electrolyzer circulation circuit; When the conductivity of the oxygen-water primary separation tank is greater than or equal to the first threshold value S1, set a first delay time and then judge whether the conductivity of the oxygen-water primary separation tank is greater than or equal to the second threshold value S2, and the second threshold value S2 is greater than the first threshold value S1; When the conductivity of the oxygen-water primary separation tank is greater than or equal to the second threshold value S2, close the electrolyzer circulation circuit, and continue to judge whether the conductivity of the oxygen-water primary separation tank is greater than or equal to the first threshold value S1; When the conductivity of the oxygen-water primary separation tank is less than the second threshold value S2, then judge whether the conductivity of the oxygen-water primary separation tank is greater than or equal to the third threshold value S3, and the third threshold value S3 is less than the second threshold value S2; When the conductivity of the oxygen-water primary separation tank is greater than the third threshold value S3, set a second delay time and then close the multifunctional hydrogen production circulation system; When the conductivity of the oxygen-water primary separation tank is less than or equal to the third threshold value S3, set the deionized water circulation circuit to operate at the maximum flow rate, and continue to judge whether the conductivity of the oxygen-water primary separation tank is greater than or equal to the first threshold value S1; Among them, when the multifunctional hydrogen production circulation system is in an operating state, obtain the real-time temperature value T1 of the oxygen-water primary separation tank, obtain the real-time temperature value T2 of the output end of the heat exchanger, obtain the set key temperature threshold value T3 of the key regulating valve of the heat exchanger, and judge whether the real-time temperature value T1 of the heat exchanger is greater than the set key temperature threshold value T3 of the key regulating valve of the heat exchanger; When the real-time temperature value T1 of the heat exchanger is greater than the set key temperature threshold value T3 of the key regulating valve of the heat exchanger, turn off the electric heater; Obtain the net heat production Qnet of the PEM electrolyzer and the heat exchange amount Qexc of the deionized water circulation circuit; When the heat generation quantity Qnet of the PEM electrolytic cell is greater than the heat exchange quantity Qexc of the deionized water circulation loop, set the real-time temperature value T2 at the output end of the heat exchanger as the set temperature threshold value T4, where the set temperature threshold value T4 is greater than the set critical temperature threshold value T3; according to the real-time temperature value T1 of the heat exchanger and the set temperature threshold value T4, adjust the opening degree of the critical regulating valve of the heat exchanger through a proportional-integral-derivative algorithm; When the heat generation quantity Qnet of the PEM electrolytic cell is less than the heat exchange quantity Qexc of the deionized water circulation loop, adjust the opening degree of the critical regulating valve of the heat exchanger through a proportional-integral-derivative algorithm according to the real-time temperature value T1 of the heat exchanger and the set critical temperature threshold value T3.

2. The control method of the multifunctional hydrogen production circulation system according to claim 1, characterized in that It further includes: Judge whether the first delay duration ends. If not, continue to judge whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold value S1. If so, judge whether the conductivity of the primary oxygen-water separation tank is greater than or equal to the second threshold value S2; Judge whether the second delay duration ends. If so, close the multifunctional hydrogen production circulation system. If not, continue to judge whether the conductivity of the primary oxygen-water separation tank is greater than the third threshold value S3.

3. The control method of the multifunctional hydrogen production circulation system according to claim 1, characterized in that, It further includes: When the conductivity of the primary oxygen-water separation tank is less than the first threshold value S1, set the deionized water circulation loop to calculate the circulating water volume passing through the deionizer according to the flow rate limits of the deionized water circulation pump and the electrolytic cell circulation pump; When the conductivity of the primary oxygen-water separation tank is greater than or equal to the first threshold S1, through calculate the first delay duration t, where Q is the circulating water volume passing through the deionizer, V is the water storage volume of the system, is the deionizer efficiency, and C(t) is the conductivity of the primary oxygen-water separation tank at different times.

4. The control method of the multifunctional hydrogen production circulation system according to claim 1, characterized in that, It further includes: When the real-time temperature value T1 of the heat exchanger is less than or equal to the set critical temperature threshold value T3 of the critical regulating valve of the heat exchanger, judge whether there is a flow rate in the deionized water circulation loop; If there is no flow rate in the deionized water circulation loop, set to close the multifunctional hydrogen production circulation system after a third delay duration. If there is a flow rate in the deionized water circulation loop, turn on the electric heater and adjust the real-time temperature value T1 of the heat exchanger to the set critical temperature threshold value T3 of the critical regulating valve of the heat exchanger.

5. The control method of the multifunctional hydrogen production circulation system according to claim 4, characterized in that, The obtaining of the heat generation quantity of the PEM electrolytic cell and the heat exchange quantity Qexc of the deionized water circulation loop includes: By calculating the calorific value of the PEM electrolyzer, where Istack is the total current of the PEM electrolyzer, Acell is the reaction area of the PEM electrolyzer, Ncell is the number of electrolytic cell sections of the PEM electrolyzer, Vcell is the voltage of the PEM electrolyzer, and Vth is the electrolysis voltage of the PEM electrolyzer; By calculating the heat dissipation of the PEM electrolyzer, where h is the heat transfer coefficient, Tstack is the stack temperature, and Tamb is the ambient temperature; By calculating the net heat generation Qnet of the PEM electrolyzer; By calculating the heat exchange amount Qexc of the deionized circulation loop, where C is the specific heat capacity of water, m is the mass of water, and Δt is the temperature difference.

6. The control method of the multifunctional hydrogen production circulation system according to claim 5, characterized in that, The adjusting of the opening degree of the critical regulating valve of the heat exchanger through a proportional-integral-derivative algorithm includes: The proportional-integral-derivative algorithm is ; where Kp, Ki, and Kd are the proportional gain coefficient, integral gain coefficient, and derivative gain coefficient, respectively, and e(t) is the deviation between the set temperature and the actual temperature.

7. The control method of the multifunctional hydrogen production circulation system according to claim 1, characterized in that It further includes: When the multifunctional hydrogen production circulation system is in an operating state, obtain the flow rate of the PEM electrolytic cell and the flow rate of the deionized water circulation loop, and calculate the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolytic cell; Obtain the relationship between the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolytic cell and the temperature of the deionized water circulation loop, and adjust the temperature of the deionized water circulation loop based on the ratio of the flow rate of the deionized water circulation loop to the flow rate of the PEM electrolytic cell.

8. The control method of the multifunctional hydrogen production circulation system according to claim 1, characterized in that, The makeup water circuit includes a pure water tank and a makeup water pump. The pure water tank is provided with a deionized water input pipeline, and the pure water tank is connected to the heat exchanger through the makeup water pump between the deionized water circulation pump.

9. The control method of the multifunctional hydrogen production circulation system according to claim 8, wherein The cathode water outlet of the PEM electrolytic cell is connected to the pure water tank through a primary hydrogen separation tank.

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