Electrolysis system

Abstract

An electrolysis system (1) comprises an electrolyzer (2) configured to convert electrical energy into chemical energy and power electronics (4) for supplying the electrolyzer (2) with the required electrical current. The power electronics (4) includes switching components (7) and a rectifier (8). A busbar (14) is also provided for electrically connecting the power electronics (4) to the electrolyzer (2). The power electronics (4) comprises several strings (5), each string (5) having switching components (7) and a rectifier (8), and each string (5) being mounted in a housing (10). The electrolysis system (1) has a support frame (15) with several slots (16), each slot (16) being configured to receive one of the housings (10) in a mounting position, so that the strings (5) can be connected to the busbar (14) in the mounting position.

Description

[0001] The invention relates to an electrolysis system comprising an electrolyzer for converting electrical into chemical energy and power electronics that provide the required electrical energy to the electrolyzer. State of the art

[0002] Electrolysis systems are used to convert electrical current into chemical energy. In the case of water electrolysis, water is split into its components, hydrogen and oxygen. Usually, only the hydrogen is used, which can be stored and converted back into electrical, thermal, or mechanical energy as needed. The electrical current to operate the electrolysis system is supplied by a power source, such as a wind turbine or a solar power plant, as direct or alternating current. Such an electrolysis system is known, for example, from DE 10 2018 215 698 A1.

[0003] The electrolyzer comprises one or more electrochemical stacks, each consisting of numerous electrochemical cells in which the actual electrochemical reaction takes place. The stacks must be supplied with a suitable direct current, provided by power electronics that include a rectifier, fuses, a contactor, and other electrical components. Such a power supply unit is also known as a string. Because the electrolyzer requires only a low DC voltage but a high current for corresponding power output, the power electronics must be connected to busbars with a large cross-section to supply the stacks with the necessary current.

[0004] In power electronics, various components can be present in multiples or only once. For example, switching components such as fuses and contactors may only be used once, while rectifiers for converting alternating current to direct current are present in multiples. The appropriate configuration depends on the required electrical power and the cost of the individual components. Advantages of the invention

[0005] The electrolysis system according to the invention is easily scalable, enabling the simple construction of power electronics across a wide power range while ensuring high reliability. The electrolysis system comprises an electrolyzer designed to convert electrical energy into chemical energy and power electronics for supplying the electrolyzer with the required electrical current. The power electronics include a rectifier, a contactor, and a fuse. The power electronics comprise multiple strings, each string containing a rectifier, a contactor, and a fuse, and each string is mounted in a portable housing.The electrolysis system further comprises a support frame with several slots, each slot being designed to accommodate one of the housings in a mounting position, and the strings being connectable to a busbar in the mounting position, with the electrical power transmitted by the strings being made available to the electrolyzer via the busbar.

[0006] The power electronics have a modular design and comprise several strings, preferably connected in parallel so that their currents add up. Each string has a slot into which it can be inserted with its housing and fixed in a mounting position. All strings can thus be easily connected to a common busbar or multiple busbars, which supply the electrolyzer with the necessary current. Thanks to the modular design, the preferably identical strings can be easily replaced or removed without affecting the function of the remaining strings. This makes it possible to selectively replace or temporarily remove only the affected string in case of a defect, while the remaining strings continue to supply the electrolyzer with electrical current.This allows the electrolyzer to continue operating at a reduced power output, which increases reliability and therefore also efficiency.

[0007] In a first advantageous embodiment of the invention, the housings of the strings have output contacts that are directly connected to the busbar by inserting the housings into the slots and thus into the mounting position. This eliminates the need for a separate electrical connection of the strings to the busbar(s) and simplifies the mounting of the housings in the slots. Furthermore, the risk of incorrect mounting, i.e., of strings being incorrectly connected to the busbars, is reduced or eliminated.

[0008] The strings are advantageously connected in parallel so that their currents add up and can be routed to the electrolyzer via busbars. Electrolyzers are usually operated at a relatively low voltage but very high currents, which necessitates busbars with a large cross-section to minimize losses. Due to the parallel connection, any number of strings can be added to provide the required current.

[0009] The strings are mounted in a housing, which can advantageously be designed as an open frame structure, a semi-open frame structure with partial cladding, or a closed housing, depending on the environment and the necessary safety regulations.

[0010] In a further advantageous embodiment of the invention, the strings or their housings are detachably fixed in the support frame, e.g., by screw connections. This allows individual housings to be easily removed and replaced without affecting the function of the remaining strings. It is particularly advantageous if several or all strings and their housings are identical in design, so that they can be easily replaced to replace individual defective strings, which can then be repaired separately and, if necessary, at a different location.

[0011] In a further advantageous embodiment, the support frame is divided into several segments, each segment comprising at least two slots for accommodating string enclosures. Such segments can be assembled to form a large power electronics unit capable of handling high power and current. The modular design allows for easy connection if, advantageously, all segments have partial busbars that can be easily connected to one another, e.g., by plugging them into each other. The partial busbars are advantageously mounted on a busbar support frame, which can be mounted on or to the support frame independently of the strings. drawing

[0012] The drawing schematically depicts an electrolysis system according to the invention. Fig. 1 the schematic structure of the entire electrolysis system, Fig. 2 a support frame without strings, Fig. 3 a rail support frame with partial current rails, Fig. 4 a complete segment of the support frame and Fig. 5. An overall representation of an electrolysis system with multiple segments. Description of the embodiments

[0013] In Fig. Figure 1 shows the entire electrolysis system 1, with only the essential components depicted. Here, electrolysis system 1 serves, for example, to split water into hydrogen and oxygen using electrical energy. The hydrogen is then used as an energy carrier, while the oxygen is either simply released into the ambient air or used for other purposes. The necessary electrical energy is supplied to electrolysis system 1 as alternating current via a power line 13 and transformed to the required voltage in a transformer 3. The electrical energy can be generated, for example, by a wind turbine or a solar power system. The transformer 3 is connected to power electronics 4, which converts the electrical output voltage of the transformer 3 into the direct current voltage required for the operation of the electrolyzer 2.Operating an electrolyzer typically requires only low voltages, but correspondingly high currents to provide the necessary power. The actual splitting of water into hydrogen and oxygen takes place in electrolyzer 2. The devices for supplying electrolyzer 2 with water or electrolyte solution and for storing the resulting hydrogen are not shown here, as they are well known.

[0014] The power electronics 4 comprises several strings 5 ​​connected in parallel, so that their output currents add up. Each string 5 provides a portion of the required electrical energy and includes switching components 7 and a rectifier 8. The switching components 7 include, in particular, fuses, contactors, and other elements to ensure the safe operation of the power electronics 4. Due to the parallel connection, each string 5 contributes only a portion of the required power. If one string 5 fails, the remaining strings 5 ​​can continue to supply their electrical power, and the electrolyzer 2 can continue to operate, albeit at a reduced power output.

[0015] In Fig. Figure 2 shows a support frame 15. This consists of an open frame structure with massive supports, the support frame being divided into individual slots 16 by struts 17. The slots 16 serve to receive a string 5 or the housing 10 in which the string 5 is mounted. By way of example, the support frame 15 shown here has four slots, whereby the housings 10 – which are not shown here for the sake of clarity – can be fixed in the support frame 15 by means of locking devices 18.

[0016] To conduct the current generated by the strings 5 ​​to the electrolyzer 2, the strings 5 ​​are connected to busbars 14. The busbars 14 – four in this example – are mounted in a separate busbar support frame 19, as shown in Fig. Figure 3 shows the number of busbars 14 being adapted to the respective requirements. The busbar support frame 19 is designed to be mounted on the support frame 15, as shown in Figure 3. Fig. Figure 4 shows that the four housings 10 each contain a string 5, which is connected to the busbars 14 or the partial busbars 114 via output contacts 11. The output contacts 11 are designed so that they make direct contact with the busbars 14 when the housings 10 are inserted into the support frame 15.

[0017] Since high-power electrolyzers 2 require a correspondingly large amount of electrical power, more than one support frame 15 can be used, forming a segment 20 in a total support frame. Fig.Figure 5 shows a possible arrangement of three segments 20 that provide the required electrical energy for an electrolyzer 2. Each of the segments 20 comprises four housings 10 with strings 5 ​​and a partial busbar 114. The partial busbars 114 are interconnected and form the busbar 14, which supplies the total power of all strings 5 ​​to the electrolyzer 2. In principle, any number of segments 20 can be combined into a single support frame to accommodate even very high power levels.

[0018] Since the partial busbars 114 are mounted on a separate busbar support frame 19, they can be installed independently of the strings 5. This simplifies overall assembly, as the busbars 14 are correspondingly heavy due to their large cross-section. Because the slots 16 and the housings 10 of the strings 5 ​​are identical, both the support frame 15 and the housings 10 can be mass-produced and therefore cost-effectively manufactured. Manufacturing from identical housings 10 also facilitates the replacement of individual defective strings 5 ​​if necessary. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2018 215 698 A1

[0002]

Claims

[1] Electrolysis system (1) with an electrolyzer (2) which is designed to convert electrical energy into chemical energy, and with power electronics (4) for supplying the electrolyzer (2) with the required electrical current, wherein the power electronics (4) comprises switching components (7) and a rectifier (8), and with a busbar (14) for electrically connecting the power electronics (4) and the electrolyzer (2), characterized by , that - the power electronics (4) comprises a plurality of strings (5), each string (5) comprising switching components (7) and a rectifier (8), and each string (5) is mounted in a housing (10), and - the electrolysis system (1) has a support frame (15) with a plurality of slots (16), wherein each slot (16) is designed to receive one of the housings (10) in a mounting position, so that the strings (5) can be connected to the busbar (14) in the mounting position. [2] Electrolysis system according to claim 1, characterized by that the housings (10) of the strings (5) have output contacts (11) which are connected to the busbar (14) by inserting the housings (10) into the mounting position. [3] Electrolysis system according to one of claims 1 or 2, characterized by that the output currents of the strings (5) in the busbar (14) add up so that the total output power of the strings (5) is available at the electrolyzer (2). [4] Electrolysis system according to one of claims 1, 2 or 3, characterized by that the housings (10) of the strings (5) are designed as an open frame structure, as a semi-open frame structure or as a closed housing. [5] Electrolysis system according to one of claims 1 to 4, characterized bythat the housings (10) of the strings (5) are releasably fixed in the mounting position in the support frame (15) so that each of the strings (5) can be replaced independently of the other strings (5). [6] Electrolysis system according to one of claims 1 to 5, characterized by that several or all strings (5) are constructed identically. [7] Electrolysis system according to one of claims 1 to 6, characterized by that the support frame (15) is divided into several segments (20), each segment (20) comprising at least two slots (16) for receiving strings (5). [8] Electrolysis system according to claim 7, characterized by that each segment (20) has a partial current rail (114) which can be electrically connected to the strings (5) mounted in the segment (20). [9] Electrolysis system according to claim 8, characterized by that several segments (20) are arranged in a row in such a way that the partial busbars (114) are electrically connected to one another. [10] Electrolysis system according to one of claims 8 or 9, characterized by that the partial current rails (114) are mounted in a rail support frame (19).

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