Control method and control device of high-temperature water electrolysis system

Abstract

A control method of a high-temperature water electrolysis system, according to a first embodiment of the present invention, comprises the steps of: determining an operating temperature of a solid oxide water electrolysis stack in a high-temperature water electrolysis system including the solid oxide water electrolysis stack; selecting an operation mode of the solid oxide water electrolysis stack by comparing the operating temperature with a supply temperature of gas supplied to the solid oxide water electrolysis stack; determining a target voltage applied to the solid oxide water electrolysis stack according to the operation mode of the solid oxide water electrolysis stack; and applying the target voltage applied to the solid oxide water electrolysis stack in a step-up manner according to the operation mode of the solid oxide water electrolysis stack.

Description

Control method and control device for high-temperature water electrolysis system

[0001] The present invention relates to a high-temperature water electrolysis system, and more particularly, to a control method and control device for a high-temperature water electrolysis system.

[0002] A water electrolysis system is a facility that produces hydrogen from water through electrolysis and consists of a hydrogen generation electrode, an oxygen generation electrode, and an electrolyte. Water electrolysis technology is largely divided into high-temperature water electrolysis and low-temperature water electrolysis depending on the operating temperature of the system. High-temperature water electrolysis technology produces hydrogen using the thermal energy and electrical energy of steam at approximately 600-800℃. Solid oxide electrolysis (SOEE) is a representative example that uses solid oxides such as ceramics as electrolytes. On the other hand, low-temperature water electrolysis technology operates at relatively low temperatures of 50-80℃ and is classified into alkaline water electrolysis (AWE), cation exchange membrane electrolysis (PEMWE), and anion exchange membrane electrolysis (AEMWE) depending on the type of electrolyte.

[0003] A solid oxide electrolysis cell (SOEC) produces hydrogen by electrolyzing water vapor, reversing the process by which a solid oxide fuel cell (SOFC) consumes hydrogen and oxygen to produce water and electricity. The SOEC stack consists of multiple layers of ceramic cells and metal components, and the amount of hydrogen produced increases in proportion to the amount of current applied to the stack. Because SOECs utilize high-temperature water vapor, they require relatively less electricity than low-temperature ones, allowing for more efficient hydrogen production.

[0004] Since SOFC generates a lot of internal heat, it has the characteristic of being operated so that changes in current, temperature, etc. applied to the stack occur gradually. SOEC technology, which is derived from SOFC technology, also applies this as is. In order to minimize changes in the thermal stress gradient applied to the inside of the stack, the current / voltage is applied to the stack that is waiting to be operated at a high temperature by gradually increasing the current / voltage to the target value in a ramp-up manner.

[0005] (Patent Document 1) Patent Publication No. 2023-0048100 (“Solid Oxide Electrolysis Cell System and Method for Operating the Cell System”)

[0006] One embodiment of the present invention provides a control method and a control device for a high-temperature electrolysis system. The control method for a high-temperature electrolysis system according to one embodiment of the present invention does not apply current / voltage in the conventional ramp-up manner, but applies current / voltage in a step-up manner so that the applied current / voltage reaches the target value instantly.

[0007] A control method of a high-temperature electrolysis system according to another embodiment of the present invention applies current / voltage by using both a step-up method and a conventional ramp-up method so that the applied current / voltage reaches a target value.

[0008] A control device of a high-temperature electrolysis system according to one embodiment of the present invention applies current / voltage in a step-up manner so that the applied current / voltage reaches a target value, or applies current / voltage using a step-up manner and a conventional ramp-up manner together.

[0009] A control method of a high-temperature electrolysis system according to a first embodiment of the present invention comprises, in a high-temperature electrolysis system including a solid oxide electrolysis stack, a step of determining an operating temperature of the solid oxide electrolysis stack, a step of selecting an operating mode of the solid oxide electrolysis stack by comparing a supply temperature of a gas supplied to the solid oxide electrolysis stack with the operating temperature, a step of determining a target voltage to be applied to the solid oxide electrolysis stack according to the operating mode of the solid oxide electrolysis stack, and a step of applying the target voltage to the solid oxide electrolysis stack in a step-up manner according to the operating mode of the solid oxide electrolysis stack.

[0010] A control method of a high-temperature electrolysis system according to one embodiment of the present invention further includes a step of releasing the target voltage applied to the solid oxide electrolysis stack in a step-down manner to make it an open circuit voltage (VCO).

[0011] In a control method of a high-temperature electrolysis system according to one embodiment of the present invention, the operation mode of the solid oxide electrolysis stack includes an exothermic mode, an endothermic mode, and a thermally neutral mode.

[0012] In a control method of a high-temperature electrolysis system according to one embodiment of the present invention, the step of selecting an operation mode of the solid oxide electrolysis stack includes selecting a thermal neutral mode when the supply temperature of the gas and the operating temperature are the same, selecting an endothermic mode when the supply temperature of the gas is greater than the operating temperature, and selecting an exothermic mode when the supply temperature of the gas is less than the operating temperature.

[0013] A control method of a high-temperature electrolysis system according to one embodiment of the present invention further includes a step of determining a thermal neutrality voltage applied to the solid oxide electrolysis stack so that the solid oxide electrolysis stack operates in a thermal neutral mode with respect to an operating temperature of the solid oxide electrolysis stack.

[0014] In a control method of a high-temperature electrolysis system according to one embodiment of the present invention, a target voltage applied to the solid oxide electrolysis stack in the exothermic mode exceeds the thermal neutrality voltage, and a target voltage applied to the solid oxide electrolysis stack in the endothermic mode is less than the thermal neutrality voltage.

[0015] A method for controlling a high-temperature electrolysis system including a solid oxide electrolysis stack according to a second embodiment of the present invention includes the steps of: determining an operating temperature of the solid oxide electrolysis stack; determining a thermal neutral voltage of the solid oxide electrolysis stack with respect to the operating temperature of the solid oxide electrolysis stack; selecting an operating mode of the solid oxide electrolysis stack by comparing a supply temperature of a gas supplied to the solid oxide electrolysis stack with the operating temperature; determining a target voltage to be applied to the solid oxide electrolysis stack according to the operating mode of the solid oxide electrolysis stack; and applying a thermal neutral voltage to the solid oxide electrolysis stack in a step-up manner according to the operating mode of the solid oxide electrolysis stack and applying the voltage to the target voltage in a ramp-up / step-down manner after a predetermined period of time.

[0016] In one embodiment of the present invention, the operation mode of the solid oxide electrolysis stack includes an exothermic mode, an endothermic mode, and a thermally neutral mode.

[0017] In one embodiment of the present invention, the step of selecting the operation mode of the solid oxide electrolysis stack includes selecting a thermal neutral mode when the supply temperature of the gas and the operating temperature are the same, selecting an endothermic mode when the supply temperature of the gas is greater than the operating temperature, and selecting an exothermic mode when the supply temperature of the gas is less than the operating temperature.

[0018] In one embodiment of the present invention, the target voltage applied to the solid oxide electrolysis stack in the exothermic mode exceeds the thermal neutrality voltage, and the target voltage applied to the solid oxide electrolysis stack in the endothermic mode is less than the thermal neutrality voltage.

[0019] A device for controlling a high-temperature electrolysis system including a solid oxide electrolysis stack according to a third embodiment of the present invention includes one or more processors and a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by the one or more processors, the one or more processors determine an operating temperature of the solid oxide electrolysis stack, determine a thermal neutral voltage of the solid oxide electrolysis stack with respect to the operating temperature of the solid oxide electrolysis stack, select an operating mode of the solid oxide electrolysis stack by comparing a supply temperature of a gas supplied to the solid oxide electrolysis stack with the operating temperature, determine a target voltage to be applied to the solid oxide electrolysis stack according to the operating mode of the solid oxide electrolysis stack, and apply a thermal neutral voltage to the solid oxide electrolysis stack in a step-up manner according to the operating mode of the solid oxide electrolysis stack and increase or decrease the thermal neutral voltage to the solid oxide electrolysis stack in a ramp-up / step-down manner after a predetermined period of time.

[0020] In one embodiment of the present invention, the operation mode of the solid oxide electrolysis stack includes an exothermic mode, an endothermic mode, and a thermally neutral mode.

[0021] In one embodiment of the present invention, the processor selects a thermal neutral mode when the supply temperature of the gas and the operating temperature are the same, selects an endothermic mode when the supply temperature of the gas is greater than the operating temperature, and selects a heating mode when the supply temperature of the gas is less than the operating temperature.

[0022] In one embodiment of the present invention, the target voltage applied to the solid oxide electrolysis stack in the exothermic mode exceeds the thermal neutral voltage, and the target voltage applied to the solid oxide electrolysis stack in the endothermic mode is less than the thermal neutral voltage.

[0023] The control method of instantly raising or lowering the current / voltage applied to the high-temperature electrolysis stack according to the control method of the high-temperature electrolysis system according to the present invention has the effect of extending the life of the stack by alleviating the thermal stress gradient of the high-temperature electrolysis stack compared to the existing ramp-up method, and can secure the durability of the high-temperature electrolysis system and can maximize the operating rate of the system.

[0024] FIG. 1 is a drawing showing a high-temperature water electrolysis system according to one embodiment of the present invention.

[0025] FIG. 2 is a diagram schematically showing the structure of a solid oxide electrolysis cell constituting a high-temperature electrolysis stack according to one embodiment of the present invention.

[0026] FIG. 3 is a graph showing the correlation between the current applied to a high-temperature electrolysis stack and the heat generated or consumed in the stack in one embodiment of the present invention.

[0027] FIG. 4 is a graph showing the temperature change of a stack in an endothermic mode in which a voltage lower than the thermal neutral voltage is applied to a high-temperature electrolysis stack according to one embodiment of the present invention.

[0028] Figure 5 is a flowchart showing a control method of a high-temperature water electrolysis system according to one embodiment of the present invention.

[0029] FIG. 6 is a drawing showing an example of a driving voltage applied to drive a stack in a step-up manner in a control method of a high-temperature electrolysis system according to one embodiment of the present invention.

[0030] FIG. 7 is a drawing showing an experimental example of driving a stack in a step-up manner in a control method of a high-temperature electrolysis system according to one embodiment of the present invention.

[0031] Figures 8a to 8c are enlarged views showing the current and temperature changes during the initial step-up period of each mode in the experimental example of Figure 7.

[0032] Figure 9 is a flowchart showing a control method of a high-temperature water electrolysis system according to another embodiment of the present invention.

[0033] FIG. 10 is a block diagram illustrating a computing device capable of implementing, in whole or in part, a control device of a high-temperature electrolysis system according to one embodiment of the present invention.

[0034] Hereinafter, with reference to the attached drawings, preferred embodiments will be described in detail so that those skilled in the art can easily practice the present invention. However, in describing preferred embodiments of the present invention in detail, if it is determined that a specific description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the same reference numerals are used throughout the drawings for parts that have similar functions and actions. In addition, in this specification, terms such as “upper,” “upper part,” “top surface,” “lower,” “lower side,” “lower surface,” and “side” are based on the drawings, and in reality, they may vary depending on the direction in which the components are arranged.

[0035] Additionally, throughout the specification, when a part is said to be "connected" to another part, this includes not only cases where it is "directly connected," but also cases where it is "indirectly connected" with other components intervening. Furthermore, unless specifically stated otherwise, "including" a component does not exclude other components, but rather implies the inclusion of other components.

[0036] FIG. 1 is a drawing showing a high-temperature electrolysis system (100) according to one embodiment of the present invention. Referring to FIG. 1, the high-temperature electrolysis system (100) according to one embodiment of the present invention includes a steam storage unit (110), a power supply unit (120), a high-temperature electrolysis stack (130), and a control device (140).

[0037] The above steam storage unit (110) stores water as high-temperature steam using a thermal energy source. The thermal energy source may include various types of thermal energy sources, such as solar heat, nuclear heat, and process heat from an iron or steel manufacturing process.

[0038] The above power supply unit (120) generates power using renewable energy such as solar, wind, bio, hydro, geothermal, ocean, waste, etc. as well as nuclear energy, and supplies the generated power to the high-temperature water electrolysis stack (130) to generate hydrogen.

[0039] The high-temperature electrolysis stack (130) generates hydrogen using steam supplied from the steam storage unit (110) and power supplied from the power supply unit (120). The high-temperature electrolysis stack (130) utilizes a high-temperature electrolysis method, and generates hydrogen by electrochemically decomposing the supplied high-temperature steam. The high-temperature electrolysis method electrolyzes steam at high temperatures, and thus consumes less electrochemical energy required for hydrogen generation than the existing low-temperature electrolysis method that operates at low temperatures, resulting in high economic efficiency and energy efficiency.

[0040] The control device (140) can determine the operating temperature of the high-temperature electrolysis stack (130), compare the operating temperature with the supply temperature of steam supplied to the electrolysis stack (130), and select the operating mode of the high-temperature electrolysis stack (130). The control device (140) can determine the target voltage to be applied to the high-temperature electrolysis stack (130) according to the operating mode of the high-temperature electrolysis stack (130), and control the power supply unit (120) so that the target voltage to be applied to the high-temperature electrolysis stack (130) can be applied in a step-up manner according to the operating mode of the high-temperature electrolysis stack (130).

[0041] In another embodiment of the present invention, the control device (140) can determine the operating temperature of the high-temperature electrolysis stack (130) and, for this operating temperature, determine the thermal neutral voltage of the high-temperature electrolysis stack (130). The control device (140) can compare the supply temperature of steam supplied to the high-temperature electrolysis stack (130) with the operating temperature of the stack (130) to select the operating mode of the high-temperature electrolysis stack (130), and determine the target voltage to be applied to the high-temperature electrolysis stack (130) according to the operating mode. Depending on the operating mode, the control device (140) can control the power supply unit (120) to apply the thermal neutral voltage to the high-temperature electrolysis stack (130) in a step-up manner and, after a certain period of time, increase or decrease the applied voltage to the target voltage in a ramp-up / step-down manner.

[0042] FIG. 2 is a schematic diagram illustrating the structure of a high-temperature electrolysis cell (10) constituting a high-temperature electrolysis stack according to one embodiment of the present invention. In the high-temperature electrolysis cell (10), an electrolysis reaction of steam occurs. At the cathode (C) electrode, a reduction reaction occurs in which steam is decomposed into hydrogen and oxygen ions, and at the anode (A) electrode, an oxidation reaction occurs in which oxygen ions transferred from the cathode (C) electrode through the electrolyte are converted into oxygen gas. From an electrochemical perspective, there is no need to inject air into the anode (A) electrode of the high-temperature electrolysis cell (10). However, since the steam supplied from the steam storage unit to the cathode (C) electrode has pressure, high-temperature air may be injected into the anode (A) electrode to maintain the temperature of the high-temperature electrolysis cell (10) and balance the pressure.

[0043] The high-temperature electrolysis cell (10) may be a solid oxide electrolysis cell (SOEC) that uses a solid oxide such as ceramic as an electrolyte, and generally uses a thin ceramic cell less than 1 mm thick, and ceramic cells and metal parts are cross-laminated in multiple layers to form a high-temperature electrolysis stack. Due to the nature of the ceramic material, there is a problem that it is easily broken by the given stress, and for this reason, it is important to maintain a pressure balance in the gas flowing into the high-temperature electrolysis cell (10). It is good to utilize high-pressure steam in terms of system operation and hydrogen production, but since the high-temperature electrolysis cell (10) is vulnerable to high-pressure gas, a separate pressure vessel (not shown) is used.

[0044] FIG. 3 is a graph showing the correlation between the current applied to a high-temperature electrolysis stack and the heat generated or consumed in the stack in one embodiment of the present invention. The graph illustrated in FIG. 3 shows the results of analyzing the heat absorption and heat generation behavior of a 5 kW-class high-temperature electrolysis stack when operated at 700°C in one embodiment of the present invention. As illustrated in FIG. 3, unlike SOFCs that always generate heat in all operating sections, SOECs show behavior that, as the applied current increases, they move from the heat absorption section to the thermal neutral point and back to the heat generation section. In addition, the amount of heat generation in a section where a very high current is applied (for example, a section where 100 A or more is applied) is less than 1 / 3 of the amount of heat generation in a general SOFC operating section (a section where 0.4 A or more is applied).

[0045] High-temperature electrolysis is an endothermic reaction (reversible heat, TΔS), but when a reaction occurs due to current application, it generates heat due to irreversible loss (electrochemical overpotential). Therefore, endothermic and exothermic reactions coexist depending on the current application, and the thermal neutrality condition is 1.284 V @ 700℃, which can be calculated using the ΔH = -247.7 kJ / mol of the electrolysis reaction equation.

[0046] FIG. 4 is a graph showing the temperature change of a stack in an endothermic mode in which a voltage lower than the thermal neutrality voltage is applied in a high-temperature electrolysis stack according to an embodiment of the present invention. In an embodiment of the present invention, when a driving current is slowly increased from 0 A to 75 A (endothermic mode lower than the thermal neutrality voltage) to a 5 kW-class high-temperature electrolysis stack, the temperature change inside the stack is examined. It shows that the temperatures of the anode endplate, steam inlet, steam outlet, air inlet, and air outlet decrease for about 1 hour and 30 minutes after the driving current is applied, and then increase again after about 1 hour and 30 minutes. It shows that the temperature increases and then stabilizes at a certain temperature after about 2 hours. In other words, when the driving current is slowly increased and applied to the stack, the occurrence of a temperature change and an internal thermal stress gradient due to it cannot be avoided.

[0047] A control method for a high-temperature electrolysis system according to one embodiment of the present invention applies a target current / voltage to the high-temperature electrolysis stack in a step-up manner when applying a driving current / voltage to the high-temperature electrolysis stack, thereby reaching the target current / voltage directly without going through the heat absorption mode. The step-up manner can avoid temperature changes that occur due to the heat absorption section in the ramp-up manner and the resulting internal thermal stress gradient.

[0048] Figure 5 is a flowchart illustrating a method for operating a high-temperature electrolysis stack in a step-up manner in a high-temperature electrolysis system according to one embodiment of the present invention. First, the operating temperature of the high-temperature electrolysis stack is determined (510). Typically, a high-temperature electrolysis stack produces hydrogen by electrolyzing high-temperature steam at about 600 to 800°C. Once the operating temperature of the high-temperature electrolysis stack is determined, the thermal neutral point of the high-temperature electrolysis stack is determined based on the operating temperature (520). As described above, the thermal neutral point of the high-temperature electrolysis stack can be calculated through ΔH = -247.7 kJ / mol of the electrolysis reaction equation. Next, the operating conditions of the high-temperature electrolysis stack are selected (530).

[0049] High-temperature electrolysis stacks do not necessarily operate under thermally neutral conditions. Typically, when supplied with heat sources (steam) in industrial applications, the temperature of the steam ranges from 100°C to 900°C, and in some cases, water may be required. For example, steel mill process heat supplies steam at around 150°C to 190°C, light-water reactors can supply steam at 150°C to 340°C depending on the steam extraction location, and fourth-generation SMR (Small Modular Reactor) reactors operate at around 700°C to 850°C. When supplied with low-temperature steam, the supplied steam must be heated by stack exhaust gas. In this case, operating the stack in exothermic mode is advantageous from the perspective of system efficiency. However, when supplied with high-temperature steam, the remaining heat can significantly increase the exhaust gas temperature. In this case, operating the stack in endothermic mode is preferable.

[0050] When the operation mode of the high-temperature electrolysis stack is the endothermic mode, the high-temperature electrolysis stack is driven with a current / voltage below the thermal neutral point (540). When the operation mode of the high-temperature electrolysis stack is the exothermic mode, the high-temperature electrolysis stack is driven with a current / voltage exceeding the thermal neutral point (550). When the operation mode of the high-temperature electrolysis stack is the thermal neutral mode, the high-temperature electrolysis stack is driven with a current / voltage of the thermal neutral point (560). When driving the high-temperature electrolysis stack, the driving voltage / current is driven with a step-up / down method in which the driving voltage / current is raised or lowered to the target value all at once, rather than a ramp-up / down method in which the driving voltage / current is gradually raised or lowered to the target value.

[0051] Figure 6 is a diagram showing an example of a voltage applied when driving a stack in a step-up manner in a high-temperature electrolysis system according to an embodiment of the present invention. The stack is driven by applying current in a step-up manner rather than a conventional ramp-up manner by switching on the voltage to a high-temperature electrolysis stack having an OCV voltage (Open Circuit Voltage, voltage when the driving current is 0 A) of 0.891 V, and similarly, the current application is stopped in a step-down manner. 1 cycle (1 st Cycle) is the endothermic section, where the voltage applied to the stack is lower than the voltage at the thermal neutral point. Cycle 2 (2 nd Cycle) is the voltage applied to the thermal neutral section is the same as the voltage at the thermal neutral point. Cycle 3 (3 rd Cycle) is an example of a case where the experiment was conducted in the heating section, where the voltage applied to the stack is higher than the voltage at the thermal neutral point. When the stack is operated in thermal neutral mode, as in Cycle 2, the change in the thermal stress gradient applied to the stack is minimal.

[0052] Fig. 7 is a drawing showing an experimental example of driving a stack in a step-up manner in a high-temperature electrolysis system according to one embodiment of the present invention. Figs. 8a to 8c are drawings showing enlarged views of the current and temperature during the initial step-up period of each mode in the experimental example of Fig. 7. That is, Fig. 8a enlarges part (a) of Fig. 7, Fig. 8b enlarges part (b) of Fig. 7, and Fig. 8c enlarges part (c) of Fig. 7.

[0053] The temperature change (△T) of the stack varies depending on whether the driving current is in the endothermic or heating section. As shown in an enlarged view in Fig. 8a, in the endothermic section, when the driving current is initially applied in a step-up manner, the temperature of the stack gradually decreases as the driving current overshoots and then stabilizes. In addition, as shown in an enlarged view in Fig. 8b, in the thermally neutral section, when the driving current is initially applied in a step-up manner, the temperature of the stack shows almost no change as the driving current overshoots and then stabilizes. In addition, as shown in an enlarged view in Fig. 8c, in the heating section, when the driving current is initially applied in a step-up manner, the temperature of the stack increases together with the increasing driving current. Therefore, if the driving current is applied to the stack in an On / Off manner, the thermal stress of the stack can be minimized and the lifespan of the stack can be extended.

[0054] FIG. 9 is a flowchart illustrating a method for driving a high-temperature electrolysis stack in a step-up manner in a high-temperature electrolysis system according to another embodiment of the present invention. As in the embodiment illustrated in FIG. 5, the step of determining the operating temperature of the high-temperature electrolysis stack (910), the step of determining the thermal neutral point of the high-temperature electrolysis stack based on the operating temperature of the high-temperature electrolysis stack (920), and the step of selecting the operating conditions of the high-temperature electrolysis stack (930) are the same. When the operating mode of the high-temperature electrolysis stack is the thermal neutral mode, the high-temperature electrolysis stack is driven in a step-up / down manner that simultaneously raises or lowers the current / voltage of the thermal neutral point (960). When the operating mode of the high-temperature electrolysis stack is the endothermic mode, the driving current / voltage of the high-temperature electrolysis stack is simultaneously raised to the current / voltage of the thermal neutral point, and then, after waiting for a certain period of time, for example, about 30 minutes to 2 hours, the stack is driven in a ramp-down manner that gradually lowers it to the target current / voltage of the endothermic mode (940). When the operating mode of the high-temperature electrolysis stack is the heating mode, the high-temperature electrolysis stack can be operated in a ramp-up manner in which the driving current / voltage is increased to the current / voltage of the thermal neutral point at once, and then slowly increased to the target current / voltage of the heating mode after waiting for a certain period of time, for example, about 30 minutes to 2 hours (950). That is, when the target voltage is not the thermal-neutral mode but the heating or endothermic mode, the high-temperature electrolysis stack driving current / voltage can be switched on at once to the thermal-neutral current / voltage, and then slowly ramped up / down to the target current / voltage of the heating / endothermic mode after waiting for a certain period of time, for example, about 30 minutes to 2 hours. The ramp-up / down rate can be, for example, approximately 0.5 to 2 A / min based on current control. When operated in this manner, the thermal shock caused by the heat absorption and generation applied to the inside of the high-temperature electrolysis stack can be minimized.The experimental examples illustrated in FIG. 7 and FIG. 8a to 8c above show that when a high-temperature electrolysis stack is controlled by switching on / off at various voltages at once, the current responds quickly and follows the controlled voltage well, and it may be more desirable to operate a high-temperature electrolysis stack in the manner illustrated in FIG. 9 to minimize thermal shock.

[0055] FIG. 10 is a block diagram showing a computing device capable of implementing, in whole or in part, a control device of a high-temperature electrolysis system according to one embodiment of the present invention.

[0056] As illustrated in FIG. 10, the computing device (900) includes at least one processor (901), a computer-readable storage medium (902), and a communication bus (903).

[0057] The processor (901) may cause the computing device (900) to operate according to the exemplary embodiments described above. For example, the processor (901) may execute one or more programs stored in a computer-readable storage medium (902). The one or more programs may include one or more computer-executable instructions, which, when executed by the processor (901), may be configured to cause the computing device (900) to perform operations according to the exemplary embodiments.

[0058] The computer-readable storage medium (902) is configured to store computer-executable instructions or program code, program data, and / or other suitable forms of information. A program (902a) stored in the computer-readable storage medium (902) includes a set of instructions executable by the processor (901). In one embodiment, the computer-readable storage medium (902) may be a memory (volatile memory such as random access memory, non-volatile memory, or a suitable combination thereof), one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, any other form of storage medium that can be accessed by the computing device (900) and capable of storing desired information, or a suitable combination thereof.

[0059] A communication bus (903) interconnects various other components of the computing device (900), including the processor (901) and computer-readable storage medium (902).

[0060] The computing device (900) may also include one or more input / output interfaces (905) that provide interfaces for one or more input / output devices (904) and one or more network communication interfaces (906). The input / output interfaces (905) and the network communication interfaces (906) are connected to a communication bus (903). The network may be any one of a cellular network, such as Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), Time Division-CDMA (TD-CDMA), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), or another cellular network.

[0061] The input / output device (904) may be connected to other components of the computing device (900) via an input / output interface (905). Exemplary input / output devices (904) may include input devices such as a pointing device (such as a mouse or a trackpad), a keyboard, a touch input device (such as a touchpad or a touchscreen), a voice or sound input device, various types of sensor devices and / or photographing devices, and / or output devices such as a display device, a printer, a speaker, and / or a network card. The exemplary input / output device (904) may be included within the computing device (900) as a component constituting the computing device (900), or may be connected to the computing device (900) as a separate device distinct from the computing device (900).

[0062] Meanwhile, embodiments of the present invention may include a program for performing the methods described herein on a computer, and a computer-readable recording medium including the program. The computer-readable recording medium may include program commands, local data files, local data structures, etc., alone or in combination. The medium may be specially designed and configured for the present invention, or may be one commonly used in the field of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical recording media such as CD-ROMs and DVDs, and hardware devices specially configured to store and execute program commands such as ROMs, RAMs, and flash memories. Examples of the program may include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0063] Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical spirit or essential characteristics thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. A method for controlling a high temperature electrolysis system including a solid oxide electrolysis stack, A step of determining the operating temperature of the above solid oxide electrolysis stack; A step of selecting an operation mode of the solid oxide electrolysis stack by comparing the supply temperature of the gas supplied to the solid oxide electrolysis stack and the operating temperature; A step of determining a target voltage applied to the solid oxide electrolysis stack according to the operation mode of the solid oxide electrolysis stack; and A control method for a high-temperature electrolysis system, comprising a step of applying a target voltage to the solid oxide electrolysis stack in a step-up manner according to the operation mode of the solid oxide electrolysis stack.

2. In paragraph 1, A control method for a high-temperature electrolysis system further comprising a step of releasing the target voltage applied to the solid oxide electrolysis stack in a step-down manner to make it an open circuit voltage.

3. In paragraph 1, The operation mode of the above solid oxide electrolysis stack is a control method of a high temperature electrolysis system including an exothermic mode, an endothermic mode, and a thermally neutral mode.

4. In paragraph 3, The step of selecting the operation mode of the above solid oxide electrolysis stack is: When the supply temperature and operating temperature of the above gas are the same, select the thermal neutral mode, If the supply temperature of the above gas is greater than the operating temperature, select the endothermic mode, A control method for a high temperature electrolysis system, wherein the heating mode is selected when the supply temperature of the above gas is lower than the operating temperature.

5. In paragraph 3, A control method for a high-temperature electrolysis system further comprising the step of determining a thermal neutral voltage applied to the solid oxide electrolysis stack so that the solid oxide electrolysis stack operates in a thermal neutral mode, with respect to the operating temperature of the solid oxide electrolysis stack.

6. In paragraph 5, A control method for a high temperature electrolysis system in which a target voltage applied to the solid oxide electrolysis stack in the above heating mode exceeds the thermal neutral voltage.

7. In paragraph 5, A control method for a high-temperature electrolysis system in which a target voltage applied to the solid oxide electrolysis stack in the above-described endothermic mode is less than a thermal neutral voltage.

8. A method for controlling a high temperature electrolysis system including a solid oxide electrolysis stack, A step of determining the operating temperature of the above solid oxide electrolysis stack; A step of determining the thermal neutral voltage of the solid oxide electrolysis stack for the operating temperature of the solid oxide electrolysis stack; A step of selecting an operation mode of the solid oxide electrolysis stack by comparing the supply temperature of the gas supplied to the solid oxide electrolysis stack and the operating temperature; A step of determining a target voltage applied to the solid oxide electrolysis stack according to the operation mode of the solid oxide electrolysis stack; and A control method for a high-temperature electrolysis system, comprising a step of applying a thermal neutral voltage to the solid oxide electrolysis stack in a step-up manner according to the operation mode of the solid oxide electrolysis stack, and applying the voltage to the target voltage in a ramp-up / down manner after a certain period of time.

9. In paragraph 8, The operation mode of the above solid oxide electrolysis stack is a control method of a high temperature electrolysis system including an exothermic mode, an endothermic mode, and a thermally neutral mode.

10. In paragraph 9, The step of selecting the operation mode of the above solid oxide electrolysis stack is: When the supply temperature and operating temperature of the above gas are the same, select the thermal neutral mode, If the supply temperature of the above gas is greater than the operating temperature, select the endothermic mode, A control method for a high temperature electrolysis system, wherein the heating mode is selected when the supply temperature of the above gas is lower than the operating temperature.

11. In paragraph 9, A control method for a high temperature electrolysis system in which a target voltage applied to the solid oxide electrolysis stack in the above heating mode exceeds the thermal neutral voltage.

12. In paragraph 9, A control method for a high-temperature electrolysis system in which a target voltage applied to the solid oxide electrolysis stack in the above-described endothermic mode is less than a thermal neutral voltage.

13. In a device for controlling a high-temperature electrolysis system including a solid oxide electrolysis stack, one or more processors; and A storage medium storing computer-readable instructions, When the computer-readable instructions are executed by the one or more processors, the one or more processors: Determine the operating temperature of the above solid oxide electrolysis stack, For the operating temperature of the above solid oxide electrolysis stack, the thermal neutral voltage of the above solid oxide electrolysis stack is determined, The operation mode of the solid oxide electrolysis stack is selected by comparing the supply temperature of the gas supplied to the solid oxide electrolysis stack and the operating temperature, The target voltage applied to the solid oxide electrolysis stack is determined according to the operation mode of the solid oxide electrolysis stack, and A control device for a high-temperature electrolysis system that applies a thermal neutral voltage to the solid oxide electrolysis stack in a step-up manner according to the operation mode of the solid oxide electrolysis stack, and after a certain period of time, increases or decreases the applied voltage to the target voltage in a ramp-up / down manner.

14. In paragraph 13, The above solid oxide electrolysis stack has an operation mode of a control device for a high temperature electrolysis system including an exothermic mode, an endothermic mode, and a thermally neutral mode.

15. In the 13th paragraph, the processor, When the supply temperature and operating temperature of the above gas are the same, select the thermal neutral mode, If the supply temperature of the above gas is greater than the operating temperature, select the endothermic mode, A control device of a high temperature electrolysis system for selecting a heating mode when the supply temperature of the above gas is lower than the operating temperature.

16. In paragraph 15, A control device for a high temperature electrolysis system in which the target voltage applied to the solid oxide electrolysis stack in the above heating mode exceeds the thermal neutral voltage.

17. In paragraph 15, A control device for a high temperature electrolysis system in which the target voltage applied to the solid oxide electrolysis stack in the above endothermic mode is less than the thermal neutral voltage.

Images