Method, apparatus, computer program and system for determining measured temperature of multi-cell electrolyzer

Abstract

To provide an improved method, apparatus, and computer program for measuring the temperature of electrolyzer cells.SOLUTION: Examples related to a method, apparatus, and computer program for determining a measured temperature of a multi-cell electrolyzer, and to a system comprising such an apparatus and a fiber-optic temperature sensor. The method comprises a step (120) of obtaining sensor information of a fiber-optic temperature sensor, wherein the sensor information comprises temperature values measured at a plurality of intervals of a fiber-optic cable used by the fiber-optic temperature sensor, and a step (150) of calculating, for each cell of the multi-cell electrolyzer, at least one temperature, based on the temperature values measured at the plurality of intervals.SELECTED DRAWING: Figure 1a

Description

[Technical field]

[0001] Examples of the invention relate to methods, devices and computer programs for determining the measured temperature of a multi-cell electrolyser, and to systems comprising such devices and fiber optic temperature sensors. [Background technology]

[0002] An electrolyser is a device that uses electricity to drive otherwise non-naturally occurring chemical reactions, such as splitting compounds, such as water, into their constituent elements by electrolysis. For example, hydrogen electrolysers and chlor-alkali electrolysers are important tools for the production of hydrogen and chlorine / sodium, respectively. For large-scale applications, electrolysers often use many individual electrolyser cells, which are often arranged in a horizontal stack.

[0003] The temperature within an individual electrolyser cell is an important metric since it is believed to be important for the overall efficiency of the electrolyser. In addition, the temperature can indicate problems with the individual cells, which may be related to a loss of efficiency or may be caused by cell degradation. Furthermore, in the case of hydrogen electrolyser cells, leaks can cause external flameless combustion, which is difficult to detect.

[0004] Measuring temperature by traditional means has many limitations. For example, measuring inside or outside the cell is very difficult due to the corrosive environment and strong electromagnetic fields. Furthermore, flames can occur anywhere in the electrolyzer, which may require multiple temperature sensors per cell. Multiple temperature sensors also require processing hardware (e.g., a Programmable Logic Controller (PLC) and a computer) to process the data, making this a costly method. Summary of the Invention [Problem to be solved by the invention]

[0005] There may be a need for improved concepts for measuring the temperature of electrolytic cell. [Means for solving the problem]

[0006] Various examples of the invention are based on the discovery that a number of measurements required for efficient monitoring of a multi-cell electrolyzer can be realized using fiber optic temperature sensors. Fiber optic temperature measurements allow separate temperature measurements at a number of points along a long fiber optic cable, which in some applications can extend for several kilometers. For example, such fiber optic temperature sensors use effects such as Raman scattering, Brillouin scattering, temperature-dependent interference properties, or temperature-dependent distributed light reflectance to determine temperature values, i.e. measurements indicative of the temperature at various sections of the fiber optic cable. These measurements are then used to determine at least one temperature value for each cell of the multi-cell electrolyzer. In practice, a single sensor (fiber optic cable and corresponding sensor) paired with post-processing of the temperature values ​​is sufficient to determine the cell-specific temperatures of the cells of the multi-cell electrolyzer. The use of a fiber optic cable as a measurement probe allows the above-mentioned limitations to be overcome by determining at least one temperature for each individual cell. The proposed concept applies to various types of electrolysers, including those with unipolar cells and those with bipolar cells, as well as those in which the cells are arranged in a series configuration and those in which the cells are arranged in parallel, e.g. in a parallel stack.

[0007] Some aspects of the invention relate to a method for determining a measured temperature of a multi-cell electrolyzer. The method includes obtaining sensor information of a fiber optic temperature sensor. The sensor information includes temperature values ​​measured at multiple sections of a fiber optic cable used by the fiber optic temperature sensor. The method includes calculating at least one temperature for each cell of the multi-cell electrolyzer based on the temperature values ​​measured at the multiple sections. In this way, the temperature of an individual cell can be determined with low effort and low cost through the use of a single measurement probe. Furthermore, since multiple temperatures can be determined for each cell, more comprehensive monitoring of the individual cells is supported.

[0008] In some embodiments, the fiber optic cable for determining the measured temperature of the multi-cell electrolyzer can extend over tens, hundreds or even thousands of meters, for example the length of the cable can range from 100 m to 10,000 m.

[0009] The optical fiber temperature measurements can be used to determine temperature values ​​at fixed sections in the optical fiber cable. These sections can be greater than 10 cm, greater than 50 cm, greater than 1 m, or even greater than 10 m. For example, these sections can be from 20 cm to 5 m. The measurements can then be mapped to individual cells of the multi-cell electrolyzer. Thus, the method can include mapping the sections to the cells of the multi-cell electrolyzer. The method can include selecting one or more temperature values ​​for each cell of the multi-cell electrolyzer based on the mapping of the sections to the cells of the multi-cell electrolyzer. The method can include calculating at least one temperature for the cell based on the one or more temperature values ​​selected for the cell. In this way, the raw measurements contained in the temperature values ​​can first be mapped to individual cells, and then these raw measurements can be used to calculate at least one respective temperature for each cell.

[0010] The previous examples simply described the processing of sensor information. In some examples, the actual measurement performed by the fiber optic temperature sensor may also be part of the method. For example, the method may include the step of generating sensor information using a fiber optic cable by the fiber optic temperature sensor.

[0011] There are various options for arranging the optical fiber cable in the cells of the multi-cell electrolyzer. For example, the optical fiber cable can be attached to the shell or the outer surface of the cells of the multi-cell electrolyzer. This allows the proposed method to be used with third party electrolyzers, since no modification of the electrolyzer is required. Furthermore, the optical fiber cable is not subject to the corrosive conditions inside the cell.

[0012] Alternatively or additionally, the optical fiber cable can be integrated into the cells, into the walls of the cells, into the heating pipes or into the cooling pipes of the multi-cell electrolyzer. Integration at least into the cells or into the walls of the cells may require modification of the multi-cell electrolyzer, but with the possible benefit of more precise measurements and in particular smaller delays in record changes. Using heating or cooling pipes for the integration of the optical fiber cable creates a compromise between the accuracy of the measurements and the effort required to equip the multi-cell electrolyzer with the optical fiber cable.

[0013] Typically, the fiber optic cable covers multiple cells of a multi-cell electrolyzer, in this way the number of fiber optic cables required can be kept small, which reduces the cost of the system.

[0014] Taking measurements at different points of the cell can allow for more comprehensive monitoring of the cell, for example, for the purpose of detecting flameless combustion, the fiber optic cable can be arranged in a manner that allows for taking multiple separate measurements per cell. One such pattern is a circular pattern. For example, the fiber optic cable can be arranged in a pattern that surrounds each of the cells in succession around their periphery. This facilitates matching of sections of the fiber optic cable with cells of a multi-cell electrolyzer, since measurements in subsequent sections often belong to the same cell.

[0015] Alternatively, the fiber optic cable can be arranged in a serpentine pattern, whereby the fiber optic cable repeatedly runs along a series of cells of a multi-cell electrolyzer, turns around and runs in the opposite direction along a series of cells, turns around again and runs along a series of cells again, again allowing multiple measurements per cell, at the cost of a more complex correspondence of sections to cells.

[0016] In some preferred embodiments, the fiber optic temperature sensor is a Raman scattering-based sensor. A Raman scattering fiber optic temperature sensor is a type of sensing device that utilizes the principles of Raman scattering to measure temperature along a fiber optic cable. This technique is particularly useful for monitoring temperature over long distances or in hostile environments. Light, typically from a laser, can be sent through a fiber optic cable. As the light travels through the fiber, it interacts with the molecular structure of the fiber material. This interaction causes some of the light to be scattered. The scattered light contains components that are frequency shifted relative to the original light; this phenomenon is known as Raman scattering. The components that are relevant for temperature sensing are the Stokes and anti-Stokes lines, which are shifted to lower and higher energies (or frequencies), respectively. The intensity of the Raman scattered light, especially the anti-Stokes component, can change with temperature.

[0017] By analyzing the ratio of anti-Stokes scattering to Stokes scattering, the temperature along the fiber can be determined. This ratio changes in a predictable manner with temperature, allowing for accurate temperature measurements. One advantage of this type of sensor can be its ability to provide temperature measurements along the entire length of the fiber. This makes it ideal for applications requiring continuous monitoring over large areas or along structures such as pipelines and power cables.

[0018] Some aspects of the invention relate to an apparatus for determining a measured temperature of a multi-cell electrolyzer. The apparatus comprises an interface circuit for acquiring sensor information of a fiber optic temperature sensor, and a processing circuit for carrying out aspects of the method relating to processing the sensor information. In this way, the temperature of individual cells can be determined with low effort and low cost through the use of a single measurement probe. Furthermore, multiple temperatures per cell can be determined, supporting more comprehensive monitoring of the individual cells.

[0019] Some aspects of the invention relate to computer programs having program code for performing aspects of the methods relating to processing sensor information when the computer program is run on a computer, processor, or programmable hardware component.

[0020] Some aspects of the invention relate to a system for a multi-cell electrolyzer, the system including the apparatus described above and a fiber optic temperature sensor having a fiber optic cable configured to generate sensor information using the fiber optic cable and provide the sensor information to the apparatus, the system being capable of performing, for example, the method described above.

[0021] As outlined above, the fiber optic cables can be attached to the shell or exterior of the cells of the multi-cell electrolyser, or the fiber optic cables can be integrated into the cells of the multi-cell electrolyser, into the cell walls, into the heating pipes or into the cooling pipes. The former option is less laborious and can be used with third party electrolysers, whereas the latter option requires additional integration effort but offers increased measurement accuracy and / or smaller delays for detecting sudden changes.

[0022] For example, a fiber optic cable can cover multiple cells of a multi-cell electrolyzer. In this way, the number of fiber optic cables required can be kept small, which reduces the cost of the system.

[0023] In some cases, the fiber optic cable can be arranged in a circular pattern around the periphery of multiple cells in succession, facilitating matching of sections of the fiber optic cable with cells of a multi-cell electrolyzer, since measurements in subsequent sections will often belong to the same cell.

[0024] Alternatively, the fiber optic cable can be arranged in a serpentine pattern, whereby the fiber optic cable repeatedly runs along a series of cells of a multi-cell electrolyzer, turns around and runs in the opposite direction along a series of cells, turns around again and runs along a series of cells again, again allowing multiple measurements per cell, at the cost of a more complex correspondence of sections to cells.

[0025] In various examples, the fiber optic cables can be arranged in a pattern that can include sub-patterns, such as a spiral sub-pattern or a zigzag sub-pattern, that can be repeated multiple times within the pattern. Each of the sub-patterns can be located in one of the cells. Using this technique, multiple measurements can be performed per cell to generate, for example, a two-dimensional temperature map per cell.

[0026] In some cases, the system may further comprise a multi-cell electrolyser. For example, the multi-cell electrolyser may be a hydrogen electrolyser or a chlor-alkali electrolyser. Hydrogen electrolysers and chlor-alkali electrolysers are among the most commonly used electrolysers.

[0027] Some examples of apparatus and / or methods will now be described, by way of example only, and with reference to the accompanying drawings in which: [Brief description of the drawings]

[0028] [Figure 1] Figure 1a is a flow chart of an example of a method for determining a measured temperature of a multi-cell electrolyser, Figure 1b is a schematic diagram of an apparatus for determining a measured temperature of a multi-cell electrolyser and of a system including such an apparatus, and Figures 1c and 1d are diagrams showing sub-patterns for use in laying out optical fiber cables. [Diagram 2] FIG. 1 is a schematic diagram of individual cell voltage and stack current measurements. [Diagram 3] FIG. 1 is a schematic diagram of an example of measuring the temperature of an individual electrolyzer cell. [Figure 4] 4a and 4b are flow charts of examples of the measurement and processing flow of the temperatures of the cells of a multi-cell electrolyser. [Diagram 5] FIG. 1 is a schematic diagram of an example electrolyzer cell surrounded by a fiber optic cable. [Figure 6] FIG. 1 is a schematic diagram of an example electrolyzer cell incorporating an interwoven fiber optic cable. [Figure 7] FIG. 1 is a schematic diagram of an example of a data processing system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Detailed Description Some examples will now be described in more detail with reference to the accompanying drawings. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of features and equivalents, and alternatives of features. Furthermore, the terms used in this specification to describe specific examples should not be construed as limiting further possible examples.

[0030] Throughout the description of the figures, the same or similar reference numbers refer to the same or similar elements and / or features, which may be the same or may be implemented in modified form while providing the same or similar functionality. The thickness of lines, layer thicknesses, and / or area sizes in the figures may be exaggerated for clarity.

[0031] When combining two elements A and B using "or", this should be understood as disclosing all possible combinations, i.e. A only, B only, as well as A and B, unless expressly specified otherwise in individual cases. Other phrases for the same combinations may be used: "at least one of A and B" or "A and / or B". This applies equally to combinations of more than two elements.

[0032] Where singular forms such as "a," "an," and "above" are used, and where the use of only a single element is not mandated, either explicitly or implicitly, additional examples may use multiple elements to achieve the same function. Where a function is described below as being achieved using multiple elements, additional examples may achieve the same function using a single element or a single processing entity. It will be further understood that "include," "including," "comprises," and / or "comprising," when used, describe specified features, numbers, steps, operations, processes, elements, components, and / or groups thereof but do not exclude the presence or addition of one or more other features, numbers, steps, operations, processes, elements, components, and / or groups thereof.

[0033] Various examples of the present invention relate to methods, devices and computer programs for determining the measured temperature of a multi-cell electrolyser, and to systems comprising such devices and fiber optic temperature sensors, optionally including additional processing circuitry and / or the multi-cell electrolyser itself.

[0034] Figure 1a shows a flow chart of an example of a method for determining measured temperatures of a multi-cell electrolyser. The method comprises a step 120 of obtaining sensor information of a fibre optic temperature sensor 20 (shown in Figure 1b). The sensor information comprises temperature values ​​measured at multiple sections of a fibre optic cable 25 (shown in Figure 1b) used by the fibre optic temperature sensor. The method comprises a step 150 of calculating at least one temperature for each cell of the multi-cell electrolyser based on the temperature values ​​measured at the multiple sections.

[0035] In the following, a short introduction is given of the various components contained or referred to in this specification. In Fig. 1b, a schematic diagram of an apparatus 10 for determining the measured temperature of a multi-cell electrolyzer is shown. The apparatus 10 comprises an interface circuit 12 for acquiring sensor information of a fiber-optic temperature sensor 20, and a processing circuit 14 for performing at least some of the operations of the method of Fig. 1a. Optionally, the apparatus 10 further comprises a memory circuit 16 for temporarily or permanently storing previous measurements or associations. The processing circuit 14 is coupled to the interface circuit 12 and to the optional memory circuit 16. The processing circuit 14, together with the interface circuit 12 (e.g. for exchanging information with the fiber-optic temperature sensor and / or the processing entity 50) and / or the optional memory circuit 16 (for storing information), can be configured to provide the functionality of the apparatus 10. For example, the apparatus 10 can provide its functionality by the processing circuit 14 executing machine-readable instructions, which can be stored in the memory circuit 16.

[0036] The device 10 communicates with the optical fiber temperature sensor 20 and thus optionally forms a system together with the optical fiber temperature sensor 20. The output of the device 10 (i.e. at least one calculated temperature per cell of the multi-cell electrolyzer) can be processed by another processing entity 50 (in addition to the cell voltages and stack currents, i.e. the currents supplied to the stack of cells). For example, the processing entity 50 can be implemented similarly to the device 10, comprising an interface, a processing circuit and optionally a storage circuit. The optical fiber temperature sensor 20 generates sensor information provided to the device 10 by means of the optical fiber cable 25. The method can thus include a step 110 of generating sensor information by the optical fiber temperature sensor 20 by means of the optical fiber cable, which can then be used to determine the cell temperatures of the individual cells. The optical fiber temperature sensor 20 can thus be configured to generate sensor information by means of the optical fiber cable and provide this sensor information to the device 10. Figure 1b further shows a multi-cell electrolyzer 100 having a plurality of cells, with optical fiber cables 25 arranged in these cells. More details of the multi-cell electrolyzer are given in relation to Figure 2. For example, the processing circuitry 50 and / or the electrolytic cell 100 may be part of a system.

[0037] In Fig. 1b, four entities are distinguished - the multi-cell electrolyser 100, the optical fiber temperature sensor 20 with the optical fiber cable 25, the device 10 used to process the sensor information provided by the optical fiber temperature sensor, and the processing entity 50 used to further process the cell temperatures (and optionally the cell voltages and stack currents). However, in some cases the device 10 and the processing entity 50 can be in the same device or part of the same device, i.e. the processing entity 50 is able to convert the sensor information of the optical fiber temperature sensor into cell temperatures. Furthermore, in some cases the device 10 and the optical fiber temperature sensor 20 can be in the same device or part of the same device, i.e. the processing of the temperature values ​​to determine the temperatures of the individual cells can be performed as part of the optical fiber temperature sensor, or the interface circuit 12 of the device can comprise a circuit for connecting to the optical fiber cable 25 and perform the temperature measurement.

[0038] The proposed concept is based on optical fiber temperature measurements. In general, such optical fiber temperature measurements are based on the effect of temperature on the optical fiber cable 25. For example, depending on the temperature, the reflection or scattering of light or sound may be different in different sections on the optical fiber cable. Different techniques exist for realizing such optical fiber temperature sensors. For example, the optical fiber temperature sensor may be a fiber Bragg grating sensor, i.e. a sensor based on the temperature-dependent change in the Bragg wavelength. Alternatively, the optical fiber temperature sensor may be a Raman scattering-based sensor, which is based on the temperature-dependent change in the length of an optical resonator. Alternatively, the optical fiber temperature sensor may be an interferometric optical fiber temperature sensor, i.e. a temperature sensor based on the temperature-dependent change in the length of an optical resonator. Alternatively, the optical fiber temperature sensor may be a Brillouin scattering-based distributed temperature sensor (based on the temperature-dependent scattering of acoustic phonons). However, the proposed concept is not limited to a specific realization of an optical fiber temperature sensor.

[0039] Fiber optic temperature sensors have in common that they allow the measurement of temperature in user-defined or system predefined intervals. For example, in one example of a fiber optic temperature sensor used to realize the proposed concept, the fiber optic temperature sensor provides measurements in 1 meter increments, i.e. a separate temperature value for every meter of a multi-kilometer length of fiber optic cable. In some examples, temperature value measurements are taken at specific points every meter, while in other examples, an average temperature value is measured over a 1 meter stretch or a specific stretch of the fiber optic cable. These temperature values ​​can then be used to calculate the temperature of the individual cells, depending on how the fiber optic cable is arranged in the electrolyzer cells. Thus, the process starts with a step 120 of obtaining sensor information having temperature values ​​(and optionally a step 110 of generating sensor information). As outlined above, the sensor information includes temperature values ​​measured in multiple intervals of the fiber optic cable used by the fiber optic temperature sensor. In other words, the sensor information includes multiple temperature values, one temperature value per interval. For example, the multiple intervals can be equidistant intervals (e.g. the 1 meter intervals mentioned above), for example defined by the fiber optic temperature sensor 20. Alternatively, the sections can be custom sections tailored to the geometry of the cells of the multi-cell electrolyzer and the pattern used to place the fiber optic cables 25 in (or within) the cells.

[0040] These temperature values ​​can then be used to calculate the temperature for the individual cells. For this purpose, information about which temperature values ​​are to be obtained in which cells of the electrolyser can be used. In the following, this information is represented as a correspondence between sections of the optical fiber cable and cells of the multi-cell electrolyser. For example, as shown in FIG. 1a, the method can include a step 130 of associating a number of sections with the cells of the multi-cell electrolyser. For example, each of the sections (or a subset of sections, if a section is between two cells or is not located at a cell) can be associated with one of the cells. Thus, each cell can have at least one (preferably several) sections associated with it (in step 130), and this association can then be used to calculate the temperature of the cell. This association can be used to perform a selection as to which temperature value is to be used to calculate at least one temperature of a cell. In other words, the method can include a step 140 of selecting one or more temperature values ​​for each cell of the multi-cell electrolyser based on the correspondence of the sections to the cells of the multi-cell electrolyser. The selected temperature value can be used to calculate at least one temperature of the cell. In other words, the method can include a step 150 of calculating at least one temperature for the cell based on one or more temperature values ​​selected for the cell. For example, in some cases, a single temperature can be calculated for each cell based on multiple intervals and thus multiple temperature values ​​associated with the cell, for example using the average or median of these temperature values. Alternatively, multiple temperatures can be calculated for each cell based on multiple intervals and thus multiple temperature values ​​associated with the cell. To detect flameless combustion in different sections of the cell, it is preferable to calculate multiple temperatures for each cell.

[0041] The correspondence between sections and cells depends on the way in which the fiber optic cable is arranged in the respective cell or in the cell. In general, two general arrangement options can be distinguished - these are either attached to the outside of the cell (for example attached to the outer shell or surface of the cell or between the cell and the insulation) or integrated in the cell. For example, the fiber optic cable can be attached to the outer shell or surface of a multi-cell electrolyser. This method is more suitable for retrofitting existing electrolysers or for use with third party electrolysers. Alternatively, the fiber optic cable can be integrated in the cell, in the cell wall, in the heating pipes or in the cooling pipes of the multi-cell electrolyser. This requires more effort. However, the closer proximity allows the measurements to be more accurate than measurements from outside the cell. In both cases, the fiber optic cable can cover several cells of the multi-cell electrolyser. For example, a single fiber optic cable may be sufficient to measure the temperature in all the cells of a multi-cell electrolyser. Alternatively, several fiber optic cables can be used, with several sections running through the several fiber optic cables. In this case, the complexity of the correspondence between intervals and cells may increase slightly.

[0042] The correspondence between the sections and the cells depends on the geometry of the electrolysis cell and the pattern used to place the fiber optic cable in the cell or cells. Figures 5 and 6 show two options for placing the fiber optic cable. Figure 5 shows a fiber optic cable surrounding the cells of the electrolysis cell. In other words, the fiber optic cable can be placed in a pattern that surrounds each cell in a continuous manner around the periphery of the cells (e.g., between the cell wall and the insulation). For example, as shown in Figure 1b, the cells of the electrolysis cell can be arranged in a horizontal stack (or alternatively, a vertical stack). The fiber optic cable can be placed in a pattern that substantially surrounds each individual cell of the stack, for example, such that each cell is surrounded (e.g., surrounded, enveloped) at least once. In some cases, each cell can be surrounded multiple times, e.g., multiple small areas per cell, to determine the average temperature over different positions per cell, or a two-dimensional temperature profile of the cell can be determined. For example, a spiral or snail pattern (e.g., having mostly straight lines as shown in FIG. 1c, or mostly curved lines (not shown)) can be used, as shown in FIG. 1c. The spiral or snail pattern can be repeated multiple times per cell, as shown in FIG. 1c, with the same (or similar) pattern being used for the other cells. Alternatively or in addition, a meander / zigzag pattern can be repeated multiple times per cell, as shown in FIG. 1d, with the same (or similar) pattern being used for the other cells. For example, if the diameter of the electrolyzer is, for example, less than 1 meter (e.g., less than the measurement accuracy of the fiber optic temperature sensor), or if it is necessary to measure the temperature of different areas on the exterior of the electrolyzer, wiring can be added, where, for example, one portion of an individual electrolyzer cell can be surrounded or covered two or three times with circular wiring (by zigzagging up and down for example 20 cm as shown in FIG. 1d, or by using a spiral / snail pattern as shown in FIG. 1c) before moving to the next spot on the same cell that is further from the exterior wall.In a more general sense, the fiber optic cable is arranged in a pattern (i.e., around a cell or in a serpentine pattern as shown in FIG. 6) that includes subpatterns, such as a spiral / snail subpattern or a serpentine / zigzag subpattern, that are repeated multiple times within the pattern. Each of the subpatterns may be arranged in exactly one of the cells (i.e., a subpattern may not cover multiple cells). Each cell may be covered by multiple repetitions of the subpattern, for example, by repeating a series of subpatterns around the periphery of each cell. Thus, the correspondence of sections to cells may be based on such circular patterns, or combinations of circular and subpattern repetitions, for example, based on knowledge of which sections are to be placed in which cells of an electrolytic cell. This may be calculated using three-dimensional computer-aided design drawings, or may be determined manually using exterior markings on the fiber optic cable.

[0043] Instead, a weave or serpentine pattern can be used, as shown in FIG. 6. In other words, the fiber optic cable can be arranged in a serpentine pattern, whereby the fiber optic cable repeatedly runs along a series of cells of a multi-cell electrolyzer, turns around, runs backward along the series of cells, turns around again, and runs along the series of cells again. With a serpentine pattern, the fiber optic cable passes through each cell multiple times. Depending on the size of the cell and the size of the section, a temperature value can be associated with the cell each time the fiber optic cable passes through the cell (or for a subset of the number of times it passes through). As with the example shown in relation to the circular pattern, the spiral / weave pattern can be combined with a smaller spiral / snail pattern, or a smaller serpentine / zigzag pattern, to cover a portion of an individual electrolyzer cell multiple times. Thus, again, the association of sections with cells can be based on such a meander or weave pattern, e.g., based on knowledge of which sections are to be placed in which cells of the electrolyzer. This can be calculated using three-dimensional computer aided design drawings, or can be determined manually using exterior markings on the fiber optic cable.

[0044] As outlined in relation to the circular pattern, in some examples, multiple temperature values ​​can be obtained for each cell, e.g., using multiple sub-patterns, to generate a two-dimensional temperature profile for each cell. For example, the act of calculating at least one temperature can include generating a two-dimensional temperature profile for the individual cell based on the temperature values ​​and based on a correspondence between the multiple zones and the cells of the multi-cellular electrolyzer. In this case, the correspondence between the multiple zones and the cells can include a correspondence between the multiple zones and a plurality of points on each cell of the multi-cellular electrolyzer, e.g., a plurality of points in a two-dimensional grid of points on each cell of the electrolyzer.

[0045] Although the present invention is mainly concerned with hydrogen and chlor-alkali electrolysers, the proposed concept is not limited to a specific type of electrolyser. For example, the proposed concept can be used for different types of (hydrogen) electrolysers such as PEM (Proton Exchange Membrane) electrolysers, alkaline electrolysers, solid oxide electrolysis-based electrolysers, or anion exchange membrane water electrolysis-based electrolysers. The proposed concept applies to various types of electrolysers, including electrolysers with monopolar cells and electrolysers with bipolar cells, as well as electrolysers in which the cells are arranged in a series configuration and electrolysers in which the cells are arranged in parallel, e.g. in a parallel stack. Monopolar electrolysers, also known as "tank-type" electrolysers, use a porous separator (e.g. a membrane) to keep the positive and negative electrodes separated. These electrodes are linked in parallel with each other and placed in a single electrolytic bath to form a cell. Multi-cell electrolysers can be built up by connecting the cells in series. Bipolar electrolysers use metal sheets or bipoles to connect adjacent cells in series. For example, one side of a bipole can be coated with a negative electrode electrocatalyst while the other side can be coated with the positive electrode electrocatalyst of the next cell. In the case of a bipolar cell, the total voltage is a combination of the cell voltages, resulting in a module that operates at higher voltages and lower currents than monopolar, tank-type designs. To form a larger multi-cell electrolyzer, multiple modules (each with multiple cells) are connected in parallel to increase the current. In general, an electrolyzer uses electricity to drive chemical reactions that would otherwise not occur naturally. In the context of the present invention, an electrolyzer is a device that splits compounds such as water into their constituent elements such as hydrogen and oxygen by electrolysis.

[0046] The calculated cell-specific temperatures are then processed by the device 10 or other processing entity 50, for example to generate an alarm in case of anomalies or to evaluate the cell's degradation over time. For example, with respect to FIG. 7, eight models are introduced and these models can be used to process the temperature data, and optionally also the individual cell voltages and stack currents. Below, some examples of such processing are given. For example, the device 10 or processing entity 50 can be configured to compare the temperature of each cell with the temperature of other cells or with the temperature of one or more reference cells. If the difference is greater than a specified difference (in percentage), a cell having a higher or lower temperature compared to other cells can be considered as anomalous. Additionally or alternatively, the device 10 or processing entity 50 can be configured to monitor the temperature of each cell over time. Additionally or alternatively, the device 10 or processing entity 50 can be configured to predict the cell temperature of the individual cells (for example using the cell voltages and stack currents) and compare the measured temperature of the individual cells with the predicted temperature. To detect H2 (hydrogen) leaks (and possible flameless combustion, which is invisible), any measured high temperature spike (instantaneous rise and fall) (e.g. compared to previous temperatures of the same cell, compared to other cells / reference cells, or compared to predicted temperatures) can be considered as an H2 flame and can generate an alarm; in other words, analysis can be performed to capture any temperature spikes that may indicate a flame caused by a (hydrogen) leak.

[0047] The interface circuitry 12 may represent one or more inputs and / or outputs for receiving and / or transmitting information within a module, between modules, or between modules of different entities, where the information may be digital (bit) values ​​according to a specified code. For example, the interface circuitry 12 may include interface circuits configured to receive and / or transmit information.

[0048] For example, the processing circuitry 14 may be implemented using any means for processing, such as one or more processing units, one or more processing devices, processors, computers, or programmable hardware components operable by appropriately adapted software. In other words, the described functionality of the processing circuitry 14 may also be implemented in software, which is then executed on one or more programmable hardware components. Such hardware components may include general-purpose processors, digital signal processors (DSPs), microcontrollers, etc.

[0049] For example, storage device 16 may comprise at least one member of the group of computer readable media such as a magnetic or optical storage medium, e.g., a hard disk drive, a flash memory, a floppy disk, a Random Access Memory (RAM), a Programmable Read Only Memory (PROM), an Erasable Programmable Read Only Memory (EPROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), or a network storage device.

[0050] Further details and aspects of the systems, methods, devices, and computer systems for determining a measured temperature are described in relation to the proposed concepts or one or more examples described above or below (e.g., Figures 2-7). The systems and methods, devices, and computer systems for determining a measured temperature may include one or more additional optional features corresponding to one or more aspects of the proposed concepts or corresponding to one or more examples described above and below.

[0051] Various examples of the present invention relate to the area of ​​electrolyser monitoring of various types, such as chlor-alkali or hydrogen electrolyser monitoring, and in particular to temperature monitoring of individual electrolyser cells, although the proposed concepts are not limited to any particular type of electrolyser.

[0052] Typically, three measurements are of interest when monitoring a multi-cell electrolyzer - these are stack current, individual cell voltage and individual cell temperature. For example, the following hardware can be used to capture such process related data (current, individual cell voltage and individual cell outer surface temperature): For example, current measurements can be performed by a local control system (typically, for each electrolyzer, the current is measured / controlled by the control system). In addition, a cell voltage measurement system can be used to accurately measure the voltage of the individual cells. A schematic diagram of individual cell voltage measurement and current measurement is shown in FIG. 2. FIG. 2 shows a simplified diagram of an electrolyzer 200 having a positive busbar 210, a negative busbar 220 and up to 150 cells (or elements), each of which has a cathode 230 and an anode 235 between the positive and negative busbars. 2, 560V DC (Direct Current) is provided by a rectifier transformer as a potential difference between the positive and negative busbars. Current measurements are performed by current measurement entity 240 and voltage measurements are performed by voltage measurement entity 250. The measured voltages at the cathode 230 and anode 235 of each cell are used to calculate the individual cell voltages, which correspond to the potential difference between the voltages measured at the cathode and anode of the cell.

[0053] Finally, as the focus of this application, a temperature measurement device based on fiber optic temperature measurement is used, which is shown in FIG. 3. FIG. 3 shows an electrolytic cell 300, which can be realized similarly to the electrolytic cell 200 shown in FIG. 2. A fiber optic temperature sensor 20 is used together with a fiber optic cable to measure the temperature in the individual cells. For example, the fiber optic temperature measurement can be used to measure the outer surface temperature of the electrolytic cell with sufficient accuracy. Optionally, the fiber optic temperature measurement can be used to perform an internal temperature measurement. However, integrating a fiber optic cable inside the cell can be complicated. As an alternative to using a fiber optic based temperature measurement device, an infrared camera can be used, outside the scope of the claims of this application.

[0054] Figures 4a and 4b provide an example of how to measure the temperature of individual cells and then process the temperature to, for example, generate an alarm. Figures 4a and 4b are flow charts of an example of a flow of measuring and processing the temperature of cells of a multi-cell electrolyzer. In the flow, data capture (temperature values) (block 410) is performed by a Fiber-Optic (FO) cable (or other means). The data is then converted (block 420) into temperature values ​​and then processed (block 430). The processing of the temperature values ​​is shown in detail in Figure 4b. For example, as shown in block 440, the individual cell temperatures can be compared to a modeled cell temperature. Additionally or alternatively, as shown in block 450, the individual cell temperatures can be compared to an optimal cell temperature. Additionally or alternatively, the individual cell temperatures can be monitored over time as shown in block 460. Additionally or alternatively, these temperatures can be checked for high temperature spikes, which may indicate a fire, as shown in block 470. Finally, appropriate follow-up actions can be taken (block 480).

[0055] The fiber optic cable can be placed in various locations in the cells of the multi-cell electrolyzer. In general, there is no limit to the way in which the fiber optic cable is attached. For example, the fiber optic cable can be attached to the exterior surface of the electrolyzer, between the electrolyzer and the insulating layer, or even within the cell itself if the installer of the electrolyzer agrees. The way of attachment can vary. In the following, two ways are shown as non-limiting examples. In FIG. 5, the fiber optic cable surrounds the electrolyzer in such a way that all the cells are covered all around, once or multiple times. FIG. 5 shows a schematic diagram of an example of an electrolyzer cell of an electrolyzer 500 surrounded by a fiber optic cable 25. Alternatively, a more "woven" pattern can be used, either horizontally or vertically, as shown in FIG. 6. FIG. 6 shows a schematic diagram of an example of an electrolyzer cell of an electrolyzer 600 with a woven fiber optic cable 25.

[0056] Fiber optic cable temperature measurement systems measure temperature over discrete distances (e.g., sections) in the cable. For example, a 6 km cable can measure temperature at 1 meter intervals (e.g., every 1 meter). It is therefore important to know where each measurement point is located. The mounting method described above and shown in Figures 5 and 6 gives the user the option to place the cable and its measurement points at the desired location in each cell.

[0057] Measurement data is collected by processing the units to which the fiber optic cable or the fiber optic temperature sensor is connected. The resulting sensor information provided by the fiber optic temperature sensor is then processed. The system comprises a processing unit 10 / 20 (which may or may not include a fiber optic temperature sensor using the fiber optic cable 25) for converting the measurements into temperature values, and another processing entity 50, such as a personal computer or a server, for processing the temperature data, for example according to the model described below. For example, as shown in FIG. 7, data from the processing unit 10 / 20 can be sent to a processing entity (for example a PC (Personal Computer)) 50 with analysis software for further processing. See FIG. 3. The processing software can analyze the individual cell temperatures and, if available, compare this temperature with predicted / calculated temperatures. In practice, the cell temperatures can be estimated based on voltage and current input data (for example obtained by the respective measurement entities shown in FIG. 2). In case of anomalies, these anomalies can be presented to the user. Analysis can also be performed to capture any temperature spikes that may indicate a fire caused by a (hydrogen) leak.

[0058] The information obtained by the temperature measurements can be combined with the individual cell voltages and stack currents. A mathematical model can be created that has the individual cell voltages and stack currents as inputs. This model can be used to predict, among other things, the individual cell temperatures. Any deviations between the model and the measured temperature values ​​can be flagged as an anomaly for further investigation.

[0059] The captured data can be received by a monitoring server, such as the processing entity 50, on which the electrolyser performance monitoring system runs. The captured data can be analyzed in one or more of the following ways: In a first model, the individual cell voltages can be compared with each other. An alarm can be generated for cells with relatively large deviations. In a second model, the dynamic behavior of the individual cells can be monitored during start-up, power-down or load change. The time to reach a new steady state gives an indication of the overall cell performance. Poor performance is likely to be related to membrane problems. In a third model, the energy balance can be used to predict the cell temperature. This cell temperature is compared to the measured cell outer surface temperature. An alarm can be generated in case of anomalies. In a fourth model, the temperature measurements of the individual cells can be compared with each other. A cell with a higher or lower temperature compared to the other cells can be considered as an anomaly if the difference is greater than a specified difference (in percentage). In a fifth model, any measured high temperature spike can be considered as an H2 flame and an alarm can be generated in order to detect H2 (hydrogen) leaks (and possible flameless combustion that is not visible). In the sixth model, the degradation over time compared to an initial model setting can be analyzed and an alarm can be generated. In the seventh model, a rapid drop in cell voltage indicates a membrane problem and in combination with an increase in cell temperature can generate an alarm. In the eighth model, based on a set of (one or more) reference cells, a baseline behavior over time (including start-up, continuous operation, and shutdown) can be determined. The behavior of each cell (as a function of current) can be compared to this baseline model.

[0060] Some aspects of the invention relate to measuring individual cell temperatures using optical fibers installed in or on each cell. For example, some of the models described above (e.g., the fourth and fifth models) can be used to process the individual cell temperatures. In addition, one or more additional models can be used. Temperature measurements can be supplemented with, for example, voltage and current measurements. For example, the temperature measurement aspects can be achieved by measuring the individual cell temperatures using optical fiber cables or other methods. A processing unit, such as the device 10 of FIG. 1b, can be used to convert the measured temperatures into a format that can be used to compare the individual cell temperatures to, for example, modeled temperatures, optimal temperatures, etc. In addition, a processing unit can be used to detect flames and send an alarm based on detected temperature spikes.

[0061] Some aspects of the invention relate to processing individual cell voltages and individual cell temperatures along with (optional) stack current measurements. This can be done by one or more of the methods described above. For this processing, cameras or robotic measurements can be used for temperature measurements instead of fiber optic measurements.

[0062] There are other ways to measure the cell exterior surface temperature, for example by measuring the surface temperature with a camera. Cameras generally have a limited viewing angle, so either multiple cameras or cameras with built-in movement or rotation mechanisms may be required. The data captured by the camera is in a different format compared to optical fiber. For example, the exact location of a particular measurement point may require some data processing to be accurately determined. Furthermore, the measurements may contain a much larger amount of data, which can be fed into more sophisticated algorithms that detect changes in temperature in much more detail. These details may have to be processed, for example, to be able to compare with calculated values. In order to detect hydrogen flames, such a camera may need to have the right characteristics to do so.

[0063] The measurement data is collected by a processing unit to which the fiber optic temperature sensor is connected. The data from this processing unit can be sent to another processing unit with analysis software for further processing, as shown in Figure 7. This processing software can analyze the individual cell temperatures, which can be compared to the calculated cell temperatures when available. In practice, the cell temperatures can be estimated based on the cell voltage and current input data. In case of anomalies, these anomalies are presented to the user.

[0064] When modeling is used to predict cell temperatures, validation can be performed between the model and the individual cell temperatures and can be monitored over time. Deviations that may indicate cell degradation or undesirable operating temperatures can then be monitored online and appropriate follow-up action can be taken. Even if the cell temperature is not modeled, the measured cell temperature can be used to improve or optimize cell performance. Furthermore, the cell temperature can be monitored over time. Changes between the individual cell temperatures are an indication of a cell problem and can be flagged for follow-up action. In case of a leak, flameless combustion may occur. Temperature spikes are measured in such cases. An alarm can be generated to notify the authorized person to take the necessary action, for example by powering down the electrolyzer.

[0065] Further details and aspects of the particular individual electrolyzer cell temperature monitoring are provided below in relation to the proposed method or one or more examples (e.g., FIGS. 1a-1b) described above or below. The particular individual electrolyzer cell temperature monitoring may include one or more additional optional features corresponding to one or more aspects of the proposed concept or corresponding to one or more examples described above or below.

[0066] Aspects and features described with respect to a particular one of the preceding examples may be combined with one or more of the additional examples, replacing the same or similar features of such additional examples, or these features may be additionally introduced into such additional examples.

[0067] Examples of the invention may further be or relate to a (computer) program, which includes program code for performing one or more of the above methods when the program is executed on a computer, a processor, or other programmable hardware component. Thus, the different method steps, operations, or processes of the above methods may also be performed by a programmed computer, a processor, or other programmable hardware component. Examples of the invention may also cover program storage devices, such as digital data storage media, which are machine-readable, processor-readable, or computer-readable and encode and / or contain machine-executable, processor-executable, or computer-executable programs and instructions. The program storage device may include or be, for example, a digital storage device, a magnetic storage medium, such as a magnetic disk and a magnetic tape, a hard disk drive, or an optically readable digital data storage medium. Other examples may include a computer, processor, control unit, (Field) Programmable Logic Array ((F)PGA), (Field) Programmable Gate Array ((F)PGA), Graphics Processor Unit (GPU), Application-Specific Integrated Circuit (ASIC), Integrated Circuit (IC) or System-on-a-Chip (SoC) system programmed to perform the steps of the methods described above.

[0068] It is further understood that the disclosure of several steps, processes, operations, or functions disclosed in the detailed description or claims should not be construed as implying that these operations are necessarily order dependent unless expressly stated in individual cases or required for technical reasons. Thus, the foregoing description does not limit the performance of several steps or functions to a particular order. Furthermore, in other examples, a single step, function, process, or operation may include several sub-steps, sub-functions, sub-processes, or sub-operations, and / or a single step, function, process, or operation may be divided into several sub-steps, sub-functions, sub-processes, or sub-operations.

[0069] Where some aspects are described in terms of an apparatus or system, these aspects should also be understood as descriptions of a corresponding method. For example, certain blocks, devices, or functional aspects of such an apparatus or system may correspond to features such as method steps of a corresponding method. Thus, aspects described in terms of a method should also be understood as descriptions of corresponding blocks, corresponding elements, properties, or functional features of a corresponding apparatus or corresponding system.

[0070] Hereby, the following claims are included in the detailed description, with each claim standing alone as an independent example. Also, in the claims, where a dependent claim refers to a specific combination with one or more other claims, other examples may include combinations of the dependent claim with the subject matter of any other dependent or independent claim. Such combinations are hereby expressly suggested, unless it is expressly stated that a particular combination is not intended in a particular instance. Moreover, the features of a claim should also be included in any other independent claim, even if that claim is not directly defined as dependent on any other independent claim.

Claims

1. 1. A method for determining a measured temperature of a multi-cell electrolytic cell, comprising the steps of: acquiring (120) sensor information of an optical fiber temperature sensor, the sensor information including temperature values ​​measured in a plurality of sections of an optical fiber cable used by the optical fiber temperature sensor; calculating (150) at least one temperature for each cell of the multi-cell electrolyzer based on the temperature values ​​measured in the plurality of zones; The method includes:

2. Corresponding (130) the plurality of zones to the plurality of zones of the multi-cell electrolytic cell; selecting (140) for each of the cells of the multi-cell electrolytic cell one or more of the temperature values ​​based on the mapping of the plurality of zones to the cells of the multi-cell electrolytic cell; calculating (150) at least one temperature for the cell based on the one or more temperature values ​​selected for the cell; The method of claim 1 , comprising:

3. 3. The method of claim 1, further comprising: generating (110) the sensor information by the fiber optic temperature sensor using the fiber optic cable.

4. 4. The method of claim 3, wherein the fiber optic cable is attached to an outer shell or surface of the cell of the multi-cell electrolyzer.

5. 4. The method according to claim 3, wherein the optical fiber cable is integrated in the cell, in the outer wall of the cell, in the heating pipes or in the cooling pipes of the multi-cell electrolyzer.

6. The method according to any one of claims 3 to 5, wherein the optical fiber cable covers multiple cells of the multi-cell electrolyzer.

7. The method of any of claims 3 to 6, wherein the optical fiber cables are arranged in a pattern surrounding each of the cells, the pattern being continuous around the periphery of the cells.

8. 8. The method according to any of claims 3 to 7, wherein the fiber optic cable is arranged in a serpentine pattern, whereby the fiber optic cable repeatedly runs along a series of the cells of the multi-cellular electrolyzer, turns around and runs in the opposite direction along the series of cells, turns around again and runs along the series of cells again.

9. 1. An apparatus (10) for determining a measured temperature of a multi-cell electrolytic cell, comprising: an interface circuit for acquiring sensor information of the optical fiber temperature sensor; A processing circuit for carrying out the method according to claim 1 or 2. An apparatus comprising:

10. 1. A system for a multi-cell electrolyzer, comprising: An apparatus according to claim 9 ; A system comprising a fiber optic temperature sensor (20) having a fiber optic cable (25), The system, wherein the fiber optic temperature sensor is configured to generate the sensor information using the fiber optic cable and provide the sensor information to the device.

11. 11. The system according to claim 10, wherein the fiber optic cable is attached to an outer shell or surface of a cell of the multi-cellular electrolyzer, or the fiber optic cable is integrated within the cell, within a wall of the cell, within a heating pipe or within a cooling pipe of the multi-cellular electrolyzer.

12. 12. The system of claim 10 or 11, wherein the fiber optic cable covers multiple cells of the multi-cell electrolyzer.

13. The system of any of claims 10 to 12, wherein the fiber optic cables are arranged in a circular pattern surrounding each of the cells, the circular pattern being continuous around the periphery of the cells.

14. 13. The system of any of claims 10 to 12, wherein the fiber optic cable is arranged in a serpentine pattern, whereby the fiber optic cable repeatedly extends along a series of the cells of the multi-cellular electrolyzer, turns around and extends in the opposite direction along the series of cells, turns around again and extends along the series of cells again.

15. 15. The system of claim 10, wherein the optical fiber cable is arranged in a pattern including a sub-pattern, such as a spiral sub-pattern or a zigzag sub-pattern, which is repeated multiple times within the pattern, each of the sub-patterns being disposed in one of the cells of the multi-cell electrolytic cell, each of the cells being covered by multiple repetitions of the sub-pattern.

16. The system according to any one of claims 10 to 15, further comprising a multi-cell electrolyser (100), said multi-cell electrolyser being a hydrogen electrolyser or a chlor-alkali electrolyser.

Images