Test system and test method for high-temperature solid oxide water electrolysis hydrogen production

Abstract

The invention discloses a test system and a test method for high-temperature solid oxide water electrolysis hydrogen production. The test system comprises a gas supply device, a heating unit, a back pressure stabilizing unit and a control unit, the back pressure stabilizing unit is connected with a cathode outlet of the SOEC stack and comprises a back pressure sensor, a first pressure regulating valve and a variable-frequency speed regulating induced draft fan; and the control unit takes back pressure data acquired by the back pressure sensor and air inlet pressure data acquired by the air inlet sensor arranged at the cathode inlet of the SOEC stack as parameters, and generates an adjusting instruction of the first pressure adjusting valve and / or the variable frequency speed adjusting induced draft fan according to a preset rule. According to the invention, performance testing can be carried out on a large-scale single electric pile and a module group composed of a plurality of small-scale or medium-scale electric piles in a large-power range; in addition, different combination modes of series connection and parallel connection between multiple electric piles and the change rule of the electrolysis performance can be tested, and then a more compact and efficient multi-electric-pile matching module can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production by water electrolysis, and in particular to a testing system and a testing method for hydrogen production by water electrolysis using high-temperature solid oxides. Background Art

[0002] There are three main ways to produce hydrogen by electrolysis of water using renewable energy: alkaline electrolysis of water, proton exchange membrane electrolysis of water, and solid oxide electrolysis of water.

[0003] Solid oxide electrolysis cell (SOEC) water electrolysis hydrogen production technology is the mainstream water electrolysis hydrogen production technology in the future because of its high electrolysis efficiency (over 90%), and can be integrated with existing petrochemical equipment to efficiently utilize the abundant waste heat of petrochemical equipment, reduce power consumption, and improve the overall efficiency of the system.

[0004] After research, the inventors found that in the prior art, the operating performance of the high-temperature solid oxide water electrolysis hydrogen production device cannot be fully tested before its assembly is completed. Therefore, it is impossible to perform performance evaluation on some key equipment or systems of the high-temperature solid oxide water electrolysis hydrogen production device by pre-determining the optimal operating parameters of the high-temperature solid oxide water electrolysis hydrogen production device corresponding to different types of fuel cells or modules.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to perform performance evaluation on some key equipment or systems of a high-temperature solid oxide water electrolysis hydrogen production device.

[0007] The present invention provides a test system for high-temperature solid oxide water electrolysis to produce hydrogen, comprising: a gas supply device for providing a gas that meets preset requirements to a solid oxide electrolysis cell SOEC, a heating unit for controlling the working temperature of the SOEC, a back pressure stabilization unit for stabilizing the back pressure of the SOEC, and a control unit;

[0008] The back pressure stabilization unit is connected to the cathode outlet of the SOEC stack, and includes a back pressure sensor arranged upstream of the cathode heat exchange and cooling unit, a first pressure regulating valve and a variable frequency speed regulating induced draft fan arranged downstream of the cathode heat exchange and cooling unit;

[0009] The control unit uses the back pressure data collected by the back pressure sensor and the intake pressure data collected by the intake sensor provided at the cathode inlet of the SOEC stack as parameters, and generates adjustment instructions for the pressure regulating valve and / or the variable frequency speed regulating induced draft fan according to preset rules.

[0010] Preferably, in an embodiment of the present invention, the air supply device includes a water purification unit, a steam generation unit, an air unit, an auxiliary air supply unit and a mixing unit, wherein:

[0011] The water purification unit includes an ultrapure water machine and an ultrapure water storage tank, which are used to purify laboratory tap water into ultrapure water suitable for SOEC electrolysis and store it;

[0012] The steam generation unit includes a steam generator for converting ultrapure water into steam;

[0013] The auxiliary gas supply unit includes a gas cylinder or a gas supply station for supplying the purge nitrogen required for SOEC electrolysis and the protective hydrogen required for the cathode of the SOEC;

[0014] The mixing unit is used to mix steam and hydrogen into hydrogen-containing mixed steam and avoid the occurrence of condensed water;

[0015] The air unit includes an air compressor, a flow meter and a control valve, and is used to continuously supply air for delivering oxygen to the anode of the SOEC.

[0016] Preferably, in an embodiment of the present invention, the heating unit comprises: a heating furnace or a heating box adapted to a single fuel cell stack or a module consisting of a plurality of fuel cell stacks.

[0017] Preferably, in the embodiment of the present invention, it also includes:

[0018] Anode heat exchange and cooling unit, the anode heat exchange and cooling unit and the cathode heat exchange and cooling unit are used to fully utilize high-temperature heat and reduce cooling losses, thereby improving system thermal efficiency.

[0019] Preferably, in the embodiment of the present invention, it also includes:

[0020] Gas drying and purification unit, used to remove water vapor and impurities in hydrogen produced by water electrolysis to ensure high purity of hydrogen product;

[0021] Preferably, in the embodiment of the present invention, it also includes:

[0022] A hydrogen storage unit is used to store product hydrogen through a hydrogen storage tank and recycle the hydrogen as cathodic protection hydrogen and purge hydrogen.

[0023] Preferably, in an embodiment of the present invention, the back pressure stabilization unit further comprises an anode voltage stabilization component connected to the anode outlet of the SOEC stack;

[0024] The anode voltage stabilizing assembly comprises a liquid separation tank, a back pressure valve and a variable frequency speed regulating induced draft fan.

[0025] Preferably, in the embodiment of the present invention, it also includes:

[0026] The hydrogen storage unit is connected to the air inlet end of the air supply pipeline; the air outlet end of the air supply pipeline provided with a second pressure regulating valve is communicated with the air inlet of the cathode heat exchange and cooling unit.

[0027] Preferably, in an embodiment of the present invention, the structure in which the air supply pipeline is connected to the air inlet of the cathode heat exchange and cooling unit includes:

[0028] The gas outlet end of the gas supply pipeline is directly connected to the air inlet of the cathode heat exchange and cooling unit; the cathode outlet pipeline connected to the cathode outlet of the SOEC stack is vertically connected to the gas supply pipeline.

[0029] Preferably, in an embodiment of the present invention, generating the adjustment instruction of the pressure regulating valve and / or the variable frequency speed regulating induced draft fan according to a preset rule includes:

[0030] When the back pressure of the cathode of the SOEC stack is greater than a first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than a second preset threshold, the variable frequency speed regulating induced draft fan is started.

[0031] Preferably, in the embodiment of the present invention, it also includes:

[0032] When the variable frequency speed regulating induced draft fan is in the starting state, the induced air volume of the variable frequency speed regulating induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulating induced draft fan according to the back pressure fluctuation of the cathode of the SOEC stack; including increasing the induced air volume when the back pressure of the cathode of the SOEC stack increases.

[0033] Preferably, in the embodiment of the present invention, it also includes:

[0034] When the pressure value at the cathode outlet of the SOEC stack is less than the third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than the fourth preset threshold, the pressure value at the cathode outlet of the SOEC stack is adjusted by adjusting the amount of hydrogen added by the second pressure regulating valve.

[0035] Preferably, in an embodiment of the present invention, it includes:

[0036] When a module consisting of a plurality of fuel cell stacks or a large single fuel cell stack is installed in the heating furnace or the heating box, a plurality of pressure rods are used to perform pressure weighting.

[0037] Preferably, in an embodiment of the present invention, the pressure rod includes a conductive rod.

[0038] In the present invention, a test method for producing hydrogen by electrolysis of water using high-temperature solid oxides is also provided, which is used for the test system for producing hydrogen by electrolysis of water using high-temperature solid oxides, and comprises the following steps:

[0039] Obtain the back pressure data and intake pressure data of the cathode of the SOEC stack;

[0040] When the back pressure data is greater than a first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than a second preset threshold, the variable frequency speed regulating induced draft fan is started.

[0041] Preferably, in the embodiment of the present invention, it also includes:

[0042] When the variable frequency speed regulating induced draft fan is in the starting state, the induced air volume of the variable frequency speed regulating induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulating induced draft fan according to the back pressure fluctuation of the cathode of the SOEC stack; including increasing the induced air volume when the back pressure of the cathode of the SOEC stack increases.

[0043] Preferably, in the embodiment of the present invention, it also includes:

[0044] When the pressure value at the cathode outlet of the SOEC stack is less than a third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than a fourth preset threshold, the second pressure regulating valve is controlled to add hydrogen.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The test system for high-temperature solid oxide water electrolysis to produce hydrogen in the present invention is provided with a gas supply device and a heating unit for the gas of the SOEC of the test object. In addition, in order to stabilize the back pressure of the SOEC, the present invention is also provided with a back pressure stabilization unit and a control unit; the cathode pressure stabilization component included in the back pressure stabilization unit in the present invention further includes a back pressure sensor, a first pressure regulating valve and a variable frequency speed regulating induced draft fan; the back pressure data and the intake pressure data collected by the intake sensor are used as parameters, and the adjustment instructions of the first pressure regulating valve and / or the variable frequency speed regulating induced draft fan are generated according to preset rules; in this way, the pressure difference of the cathode pipeline of the SOEC stack can be adjusted by the power change of the variable frequency speed regulating induced draft fan, thereby stabilizing the SOEC back pressure.

[0047] From the above, it can be seen that the present invention, by providing a gas supply device, a heating unit, a back pressure stabilization unit and a control unit, can not only perform performance tests on large single fuel cells within a larger power range, but also perform performance tests on modules composed of multiple small or medium-sized fuel cells; further, the present invention can also test the changes in electrolytic performance of different series and parallel combinations of multiple fuel cells, thereby obtaining a more compact and efficient multi-fuel cell matching module.

[0048] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, and to make the above and other purposes, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] Figure 1 It is a schematic diagram of the structure of the test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to the present invention;

[0051] Figure 2 It is a structural schematic diagram of the back pressure stabilization unit described in the present invention.

[0052] Figure 3 It is another structural schematic diagram of the back pressure stabilization unit described in the present invention;

[0053] Figure 4 This is a schematic diagram of the structure of the air supply pipeline in the present invention.

[0054] Figure 5 This is another structural schematic diagram of the air supply pipeline described in the present invention.

[0055] Figure 6 It is another structural schematic diagram of the gas supplement pipeline described in the present invention. DETAILED DESCRIPTION

[0056] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0057] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0058] In this document, the terms "first", "second", etc. are used to distinguish two different elements or parts, and are not used to limit a specific position or relative relationship. In other words, in some embodiments, the terms "first", "second", etc. can also be interchangeable.

[0059] Embodiment 1

[0060] In order to evaluate the performance of some key equipment or systems of high-temperature solid oxide water electrolysis hydrogen production device, refer to Figure 1 and Figure 2 In an embodiment of the present invention, a test system for high-temperature solid oxide water electrolysis to produce hydrogen is provided, comprising: a gas supply device 01 for providing a gas meeting preset requirements to a solid oxide electrolysis cell SOEC, a heating unit 02 (i.e., a heating furnace or a heating box) for controlling the working temperature of the SOEC, a back pressure stabilization unit 03 for stabilizing the back pressure of the SOEC, and a control unit (not shown in the figure);

[0061] The back pressure stabilization unit 03 is connected to the cathode outlet of the SOEC stack, and includes a back pressure sensor 32 arranged upstream of the cathode heat exchange and cooling unit 31, a first pressure regulating valve 33 and a variable frequency speed regulating induced draft fan 34 arranged downstream of the cathode heat exchange and cooling unit 31; the control unit uses the back pressure data collected by the back pressure sensor 32 and the intake pressure data collected by the intake sensor 35 arranged at the cathode inlet of the SOEC stack as parameters, and generates control instructions for the first pressure regulating valve 33 and / or the variable frequency speed regulating induced draft fan 34 according to preset rules.

[0062] Preferably, the air supply device 01 in the embodiment of the present invention may include a water purification unit 11 , a steam generation unit 12 , an air unit 13 , an auxiliary air supply unit 14 and a mixing unit 15 .

[0063] In practical applications, the water purification unit 11 in the embodiment of the present invention may include an ultrapure water machine and an ultrapure water storage tank, which are used to purify laboratory tap water into ultrapure water suitable for SOEC electrolysis and store it, and then control the operation time of the ultrapure water machine according to the liquid level of the ultrapure water storage tank;

[0064] The steam generation unit 12 includes a steam generator for converting ultrapure water into steam; the auxiliary gas supply unit includes a gas cylinder or a gas supply station for supplying the purge nitrogen required for SOEC electrolysis and the protective hydrogen required for the cathode of SOEC; the mixing unit 15 is used to mix steam and hydrogen into hydrogen-containing mixed steam and avoid the occurrence of condensed water; the air unit 13 includes an air compressor, a flow meter and a control valve, which is used to continuously supply air for transporting oxygen to the anode of SOEC.

[0065] The heating unit 02 in the embodiment of the present invention may include a heating furnace or a heating box adapted to a single fuel cell stack or a module consisting of multiple fuel cell stacks.

[0066] In practical applications, the embodiment of the present invention may further include: an anode heat exchange and cooling unit 36, a gas drying and purification unit 37, and a hydrogen storage unit 38, wherein:

[0067] The anode heat exchange and cooling unit 36 ​​and the cathode heat exchange and cooling unit 31 are used to fully utilize the high-temperature heat and reduce cooling losses, thereby improving the thermal efficiency of the system;

[0068] The gas drying and purification unit 37 is connected to the variable frequency speed regulating induced draft fan 34 to remove water vapor and impurities in the hydrogen produced by electrolysis of water to ensure the high purity of the hydrogen produced;

[0069] The hydrogen storage unit 38 is used to store the product hydrogen through a hydrogen storage tank and recycle the hydrogen as cathodic protection hydrogen and purge hydrogen.

[0070] Preferably, the anode back pressure stabilization unit in the embodiment of the present invention includes an anode voltage stabilization component 39 connected to the anode outlet of the SOEC stack; the anode voltage stabilization component 39 may specifically include a liquid separator tank, a back pressure valve and a variable frequency speed regulating induced draft fan.

[0071] Preferably, in an embodiment of the present invention, when a module consisting of multiple battery stacks or a large single battery stack is installed in a heating furnace or a heating box, multiple pressure rods are used for pressure rod weighting. Further, in an embodiment of the present invention, the pressure rod can preferably be a conductive rod.

[0072] The embodiments of the present invention can use not only a single ceramic pressure rod to weigh a large single battery stack or a module composed of multiple battery stacks, but also multiple pressure rods to weigh the battery; multiple pressure rods are beneficial to uniform pressure distribution; preferably, for a large single battery stack or a large module, two or more external conductive rods can be used as pressure rods, that is, the conductive rods are used for both conduction and as weight-bearing elements, which is simple and convenient.

[0073] In an embodiment of the present invention, a specific method of generating a control instruction for the first pressure regulating valve and / or the variable frequency speed regulating induced draft fan according to a preset rule may include:

[0074] When the back pressure of the cathode of the SOEC stack is greater than the first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than the second preset threshold, the variable frequency speed regulating induced draft fan is started. The first preset threshold and the second preset threshold in the embodiment of the present invention can be determined by those skilled in the art based on experience or a limited number of experiments, and are not specifically limited here.

[0075] It should be noted that excessive back pressure at the cathode of the SOEC stack and too small a difference between the intake pressure data and the back pressure will affect the normal operation of the SOEC. For this reason, in an embodiment of the present invention, the variable frequency speed regulating induced draft fan is started to induce air, thereby avoiding poor hydrogen flow in the SOEC.

[0076] In addition, in order to further improve the stability of back pressure, the embodiments of the present invention may also include: when the variable frequency speed regulation induced draft fan is in the starting state, the induced air volume of the variable frequency speed regulation induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulation induced draft fan according to the back pressure fluctuation of the cathode of the SOEC stack; including, when the back pressure of the cathode of the SOEC stack increases, increasing the induced air volume.

[0077] In summary, the test system for high-temperature solid oxide water electrolysis to produce hydrogen in the embodiment of the present invention is provided with a gas supply device and a heating unit for the gas of the SOEC of the test object. In addition, in order to stabilize the back pressure of the SOEC, a back pressure stabilization unit and a control unit are also provided in the embodiment of the present invention; the cathode pressure stabilization component included in the back pressure stabilization unit in the embodiment of the present invention further includes a back pressure sensor, a first pressure regulating valve and a variable frequency speed regulating induced draft fan; the back pressure data and the intake pressure data collected by the intake sensor are used as parameters, and control instructions for the first pressure regulating valve and / or the variable frequency speed regulating induced draft fan are generated according to preset rules; in this way, the pressure difference of the cathode pipeline of the SOEC stack can be adjusted by the power change of the variable frequency speed regulating induced draft fan, thereby stabilizing the SOEC back pressure.

[0078] From the above, it can be seen that the embodiment of the present invention, by providing a gas supply device, a heating unit, a back pressure stabilization unit and a control unit, can not only perform performance tests on large single fuel cells within a larger power range, but also perform performance tests on modules composed of multiple small or medium-sized fuel cells; further, the embodiment of the present invention can also test the changes in electrolytic performance of different series and parallel combinations of multiple fuel cells, thereby obtaining a more compact and efficient multi-fuel cell matching module.

[0079] Embodiment 2

[0080] On the basis of the first embodiment, further, in the embodiment of the present invention, as Figure 3 As shown, it can also include an air supply pipeline 04; specifically, the pipeline between the hydrogen storage units is connected to the air inlet end of the air supply pipeline 04; the air outlet end of the air supply pipeline 04 provided with a second pressure regulating valve 41 is connected to the air inlet of the cathode heat exchange and cooling unit 31.

[0081] The inventors have found through research that when the hydrogen production of SOEC is too small, if the smoothness of the transmission of the product crude hydrogen in the cathode pipeline of the SOEC stack is maintained simply by increasing the power of the variable frequency speed regulation induced draft fan, the pressure at the cathode outlet of the SOEC stack will suddenly become too small, thereby causing a negative impact on the working SOEC stack. For this reason, in order to further improve the stability of the SOEC back pressure, the embodiment of the present invention is further provided with a gas replenishment pipeline 04 on the basis of the setting; to replenish the product hydrogen in the hydrogen storage unit to the pipeline at the cathode outlet of the SOEC stack.

[0082] Preferably, in order to avoid a sudden increase in the pressure on the cathode outlet of the SOEC stack when the gas supply pipeline 04 is replenished with hydrogen, refer to Figure 4 and Figure 5 In the embodiment of the present invention, the air supply pipeline is configured so that the outlet end of the air supply pipeline 04 is directly connected to the air inlet of the cathode heat exchange and cooling unit 31; the cathode outlet pipeline connected to the cathode outlet of the SOEC stack is vertically connected to the air supply pipeline, or the angle between the cathode outlet pipeline connected to the cathode outlet of the SOEC stack and the air supply pipeline is less than 90 degrees; in this way, the faster supplementary hydrogen in the air supply pipeline 04 will flow in a straight line to the cathode heat exchange and cooling unit 31, and will not generate pressure on the cathode outlet of the SOEC stack, thereby optimizing the stabilizing effect on the SOEC back pressure.

[0083] Corresponding to the air supply pipeline, in the embodiment of the present invention, the specific method of generating the control instruction of the second pressure regulating valve according to the preset rule may include:

[0084] When the pressure value at the cathode outlet of the SOEC stack is less than the third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than the fourth preset threshold, the amount of hydrogen added is adjusted by the second pressure regulating valve to adjust the pressure value at the cathode outlet of the SOEC stack. The third preset threshold and the fourth preset threshold in the embodiment of the present invention can be determined by those skilled in the art based on experience or a limited number of experiments, and are not specifically limited here.

[0085] Preferably, reference Figure 6 In an embodiment of the present invention, the cathode heat exchange and cooling unit includes a cathode heat exchange subunit and a cathode cooling subunit; in an embodiment of the present invention, the air supply pipeline 04 is configured such that the outlet end of the air supply pipeline is located between the cathode heat exchange subunit and the cathode cooling subunit.

[0086] Embodiment 3

[0087] On the basis of Example 1 and Example 2, the embodiment of the present invention further provides a test method for producing hydrogen by electrolysis of water using high-temperature solid oxides, comprising the steps of:

[0088] Obtain the back pressure data and intake pressure data of the cathode of the SOEC stack;

[0089] When the back pressure data is greater than a first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than a second preset threshold, the variable frequency speed regulating induced draft fan is started.

[0090] Specifically, when the back pressure of the cathode of the SOEC stack is too large, and the difference between the intake pressure data and the back pressure is too small, the normal operation of the SOEC will be affected. For this reason, in an embodiment of the present invention, the variable frequency speed regulating induced draft fan is started to induce air, thereby avoiding the poor flow of hydrogen production in the SOEC.

[0091] In addition, in order to further improve the stability of back pressure, the embodiments of the present invention may also include: when the variable frequency speed regulation induced draft fan is in the starting state, according to the back pressure fluctuation of the cathode of the SOEC stack, the induced air volume of the variable frequency speed regulation induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulation induced draft fan; including, when the back pressure of the cathode of the SOEC stack increases, increasing the induced air volume.

[0092] In summary, the test system for high-temperature solid oxide water electrolysis to produce hydrogen in the embodiment of the present invention is provided with a gas supply device and a heating unit for the gas of the SOEC of the test object. In addition, in order to stabilize the back pressure of the SOEC, a back pressure stabilization unit and a control unit are also provided in the embodiment of the present invention; the cathode pressure stabilization component included in the back pressure stabilization unit in the embodiment of the present invention further includes a back pressure sensor, a first pressure regulating valve and a variable frequency speed regulating induced draft fan; the back pressure data and the intake pressure data collected by the intake sensor are used as parameters, and control instructions for the first pressure regulating valve and / or the variable frequency speed regulating induced draft fan are generated according to preset rules; in this way, the pressure difference of the cathode pipeline of the SOEC stack can be adjusted by the power change of the variable frequency speed regulating induced draft fan, thereby stabilizing the SOEC back pressure.

[0093] From the above, it can be seen that the embodiment of the present invention, by providing a gas supply device, a heating unit, a back pressure stabilization unit and a control unit, can not only perform performance tests on large single fuel cells within a larger power range, but also perform performance tests on modules composed of multiple small or medium-sized fuel cells; further, the embodiment of the present invention can also test the changes in electrolytic performance of different series and parallel combinations of multiple fuel cells, thereby obtaining a more compact and efficient multi-fuel cell matching module.

[0094] In order to further improve the stability of the SOEC back pressure, the embodiment of the present invention is further provided with a gas supply pipeline on the basis of the setting; to replenish the product hydrogen in the hydrogen storage unit to the pipeline at the cathode outlet of the SOEC stack.

[0095] Preferably, in order to avoid a sudden increase in the pressure on the cathode outlet of the SOEC stack when the gas supply pipeline replenishes hydrogen, the gas supply pipeline in the embodiment of the present invention is configured so that the gas outlet end of the gas supply pipeline is directly connected to the gas inlet of the cathode heat exchange and cooling unit, or, in the embodiment of the present invention, the cathode heat exchange and cooling unit includes a cathode heat exchange sub-unit and a cathode cooling sub-unit; the gas supply pipeline in the embodiment of the present invention is configured so that the gas outlet end of the gas supply pipeline is located between the cathode heat exchange sub-unit and the cathode cooling sub-unit.

[0096] The cathode outlet pipeline connected to the cathode outlet of the SOEC stack is vertically connected to the gas supply pipeline; in this way, the faster supplementary hydrogen in the gas supply pipeline will flow in a straight line to the cathode heat exchange and cooling unit, and will not generate pressure on the cathode outlet of the SOEC stack, thereby optimizing the stabilizing effect on the SOEC back pressure.

[0097] Corresponding to the air supply pipeline, in the embodiment of the present invention, the control instruction of the second pressure regulating valve can be further generated according to the preset rules, including:

[0098] When the pressure value at the cathode outlet of the SOEC stack is less than the third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than the fourth preset threshold, the pressure value at the cathode outlet of the SOEC stack is adjusted by adjusting the amount of hydrogen added by the second pressure regulating valve.

[0099] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A test system for producing hydrogen by electrolysis of water using high-temperature solid oxides, characterized in that: include: A gas supply device for providing gas that meets preset requirements to the solid oxide electrolysis cell SOEC, a heating unit for controlling the working temperature of the SOEC, a back pressure stabilizing unit for stabilizing the back pressure of the SOEC, and a control unit; The back pressure stabilization unit is connected to the cathode outlet of the SOEC stack, and includes a back pressure sensor arranged upstream of the cathode heat exchange and cooling unit, a first pressure regulating valve and a variable frequency speed regulating induced draft fan arranged downstream of the cathode heat exchange and cooling unit; The control unit uses the back pressure data collected by the back pressure sensor and the intake pressure data collected by the intake sensor provided at the cathode inlet of the SOEC stack as parameters, and generates adjustment instructions for the pressure regulating valve and / or the variable frequency speed regulating induced draft fan according to preset rules.

2. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: The gas supply device comprises a water purification unit, a steam generation unit, an air unit, an auxiliary gas supply unit and a mixing unit, wherein: The water purification unit includes an ultrapure water machine and an ultrapure water storage tank, which are used to purify laboratory tap water into ultrapure water suitable for SOEC electrolysis and store it; The steam generation unit includes a steam generator for converting ultrapure water into steam; The auxiliary gas supply unit includes a gas cylinder or a gas supply station for supplying the purge nitrogen required for SOEC electrolysis and the protective hydrogen required for the cathode of the SOEC; The mixing unit is used to mix steam and hydrogen into hydrogen-containing mixed steam and avoid the occurrence of condensed water; The air unit includes an air compressor, a flow meter and a control valve, and is used to continuously supply air for delivering oxygen to the anode of the SOEC.

3. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: The heating unit includes: a heating furnace or a heating box adapted to a single battery stack or a module consisting of multiple battery stacks.

4. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: Also includes: Anode heat exchange and cooling unit, the anode heat exchange and cooling unit and the cathode heat exchange and cooling unit are used to fully utilize high-temperature heat and reduce cooling losses, thereby improving system thermal efficiency.

5. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: Also includes: The gas drying and purification unit is used to remove water vapor and impurities from the hydrogen produced by water electrolysis to ensure the high purity of the hydrogen product.

6. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: Also includes: A hydrogen storage unit is used to store product hydrogen through a hydrogen storage tank and recycle the hydrogen as cathodic protection hydrogen and purge hydrogen.

7. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 1, characterized in that: The back pressure stabilization unit also includes an anode voltage stabilization component connected to the anode outlet of the SOEC stack; The anode voltage stabilizing assembly comprises a liquid separation tank, a back pressure valve and a variable frequency speed regulating induced draft fan.

8. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 6, characterized in that: Also includes: The hydrogen storage unit is connected to the air inlet end of the air supply pipeline; the air outlet end of the air supply pipeline provided with a second pressure regulating valve is connected to the air inlet of the cathode heat exchange and cooling unit.

9. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 8, characterized in that: The structure in which the air supply pipeline is connected to the air inlet of the cathode heat exchange and cooling unit includes: The gas outlet end of the gas supply pipeline is directly connected to the air inlet of the cathode heat exchange and cooling unit; the cathode outlet pipeline connected to the cathode outlet of the SOEC stack is vertically connected to the gas supply pipeline.

10. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 8, characterized in that: The step of generating the adjustment instructions for the pressure regulating valve and / or the variable frequency speed regulating induced draft fan according to the preset rules includes: When the back pressure of the cathode of the SOEC stack is greater than a first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than a second preset threshold, the variable frequency speed regulating induced draft fan is started.

11. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 10, characterized in that: Also includes: When the variable frequency speed regulating induced draft fan is in a starting state, the induced air volume of the variable frequency speed regulating induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulating induced draft fan according to the back pressure fluctuation of the cathode of the SOEC stack; Including increasing the amount of induced air when the back pressure of the cathode of the SOEC stack increases.

12. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 11, characterized in that: Also includes: When the pressure value at the cathode outlet of the SOEC stack is less than the third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than the fourth preset threshold, the pressure value at the cathode outlet of the SOEC stack is adjusted by adjusting the amount of hydrogen added by the second pressure regulating valve.

13. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 3, characterized in that: include: When a module consisting of a plurality of fuel cell stacks or a large single fuel cell stack is installed in the heating furnace or the heating box, a plurality of pressure rods are used to perform pressure weighting.

14. The test system for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 12, characterized in that: The pressure rod comprises a conductive rod.

15. A test method for producing hydrogen by electrolysis of water using high-temperature solid oxides, used in the test system for producing hydrogen by electrolysis of water using high-temperature solid oxides as claimed in any one of claims 1 to 14, characterized in that: Includes steps: Obtain the back pressure data and intake pressure data of the cathode of the SOEC stack; When the back pressure data is greater than a first preset threshold, or when the difference between the intake pressure data and the back pressure data is less than a second preset threshold, the variable frequency speed regulating induced draft fan is started.

16. The test method for producing hydrogen by electrolysis of water using high-temperature solid oxides according to claim 15, characterized in that: Also includes: When the variable frequency speed regulating induced draft fan is in a starting state, the induced air volume of the variable frequency speed regulating induced draft fan is adjusted by the first pressure regulating valve or the output power of the variable frequency speed regulating induced draft fan according to the back pressure fluctuation of the cathode of the SOEC stack; Including increasing the amount of induced air when the back pressure of the cathode of the SOEC stack increases.

17. The test method for producing hydrogen by electrolysis of water using high temperature solid oxides according to claim 16, characterized in that: Also includes: When the pressure value at the cathode outlet of the SOEC stack is less than a third preset threshold, or when the difference between the intake pressure data and the back pressure data is greater than a fourth preset threshold, the second pressure regulating valve is controlled to add hydrogen.

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