Method for detecting a malfunction, tank system, computer program product and storage means

Abstract

The present invention relates to a method for detecting a malfunction of a fuel outlet assembly (16) in a tank system (11) for a fuel cell system (10), comprising the steps: performing a start operation of the fuel cell system (10) and thereby conducting fuel out of the fuel tank (12, 13, 14) through a fuel line arrangement (15); detecting a refilling value concerning a refilling of fuel via the fuel line arrangement (15) into at least one fuel tank (12, 13, 14) during the starting operation; providing a reference refilling value; performing a comparison between the refilling value determined during the start operation and the reference refilling value provided; and detecting a malfunction of the fuel outlet assembly (16) on the basis of the comparison. The invention also relates to a tank system (11) and to a computer program product (23) for carrying out the method, as well as to a computer-readable storage medium (24) on which such a computer program product (23) is stored.

Description

[0001] Description

[0002] title

[0003] Method for detecting a malfunction, tank system, computer program product and storage means

[0004] The present invention relates to a method for detecting a malfunction in a gas system, and in particular in a tank system of a fuel cell system. The invention further relates to a tank system in or with which such a method can be carried out, a corresponding computer program product, and a computer-readable storage medium on which such a computer program product is stored.

[0005] State of the art

[0006] Fuel cell systems typically have complex tank systems. For example, DE 10 2017 212 485 A1 describes a system for storing fuel in a tank system for a vehicle. The tank system comprises tubular tank containers and a high-pressure fuel distributor with integrated control and safety technology. The tank containers are made of metal and are connected to the high-pressure fuel distributor with integrated control and safety technology to form a modular module with a flexible geometry.

[0007] During ferry operation, the tanks should be as well protected as possible against mechanical and / or thermal stresses such as vibrations, braking, or acceleration. This also applies to the protection of the tanks in the event of an accident. Furthermore, it is desirable to constantly monitor the tank system in order to detect any malfunctions in the tank system as early as possible. This always presents a challenge when using multiple tanks.

[0008] Within the scope of the present invention, approaches to solutions are proposed in order to improve known methods and systems for detecting a malfunction in a tank system of a fuel cell system. In particular, a method according to claim 1, a tank system according to claim 7, a computer program product according to claim 9 and a computer-readable storage medium according to claim 10 are proposed. Further embodiments of the invention emerge from the subclaims, the description and the figures. Features that are described in connection with the method also apply in connection with the tank system according to the invention, the computer program product according to the invention, the storage medium according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is and / or can always be made reciprocal.

[0009] According to a first aspect of the present invention, a method is proposed for detecting a malfunction of a fuel outlet arrangement in a tank system, in particular for a fuel cell system or an alternative gas system, wherein the tank system comprises a plurality of fuel tanks, a fuel line arrangement for conducting fuel from the fuel tanks, and a fuel outlet arrangement with an outlet means for each fuel tank for the controlled conduction of fuel from the fuel tanks into the fuel line arrangement. The method comprises the following steps:

[0010] - Carrying out a start-up operation, in particular of the fuel cell system or the alternative gas system, and in doing so, conducting fuel from the fuel tanks through the fuel line arrangement,

[0011] - Determining a backfilling value relating to a backfilling of fuel via the fuel line arrangement into at least one fuel tank during the starting operation,

[0012] - Providing a reference backfill value, - Performing a comparison between the determined backfill value during start-up operation and the provided reference backfill value, and

[0013] - Detecting a malfunction of the fuel outlet assembly based on the comparison.

[0014] Within the scope of the present invention, it was discovered that the backfill value during startup operation can be used to draw meaningful conclusions regarding a possible malfunction of the fuel outlet arrangement in a relatively simple manner. In particular, it was recognized that a specific malfunction can be detected based on an exceptionally high backfill during a subsequent startup or subsequent operation without interim refueling of the fuel tanks.

[0015] If all outlet valves of the outlet devices on the fuel tanks comply with the permissible pressure drop, a brief pressure increase will occur when switching to a reduced fuel mass flow or consumer mass flow. This means that an increased valve throttling effect on an individual fuel tank leads to a higher tank pressure in this fuel tank than in the other fuel tanks during an empty tank run with a high fuel mass flow or during increased operation with an increased or higher fuel mass flow. The one faulty fuel tank is, so to speak, lagging behind. If the tank system is subsequently operated with a sufficiently small or with the predefined and / or predefinable reduced fuel mass flow, this can lead to backfilling from one fuel tank into the other tanks. If such backfilling is detected, a corresponding malfunction can be concluded.

[0016] Within the scope of the method, predefined measures can also be initiated based on the detected and / or displayed malfunction. This means that if the malfunction or at least one malfunction is detected, at least one predefined measure can be initiated. This measure can be understood as the output of a visual and / or acoustic warning signal. The warning signal can be output acoustically and / or visually in a manner that is perceptible to a user of the tank system and / or the fuel cell system, for example, in the form of a driver of a vehicle with the fuel cell system.

[0017] The malfunction can be detected and subsequently displayed. Displaying the malfunction can be understood as the output of a warning signal as described above. Furthermore, displaying the malfunction can be understood as the generation of a warning signal that is stored in a memory, from which it can be read by a specialist, for example, during an inspection of the tank system. Based on the read warning signal, conclusions can be drawn about a malfunction that may have occurred or is still present. Measures can then be taken to prevent the malfunction, at least in the future.

[0018] The outlet means can have outlet valves which, in a method according to the invention, can all be electrically controlled simultaneously or essentially simultaneously. In particular, the outlet valves can be controlled in parallel at the start or during start-up operation of the fuel cell system. The electrical control can be understood to mean that the outlet valves are controlled, if possible, into a release state for conducting the fuel from the respective fuel tank into the fuel line arrangement. The outlet valves can be understood to be tank valves that are each installed directly or essentially directly on the fuel tanks. A suitable extraction filter can be positioned on each outlet valve. The outlet valve and extraction filter preferably form the essential and / or sole component of the respective outlet means. The fuel tanks are preferably understood to be hydrogen tanks.Detecting and potentially displaying a malfunction of the fuel outlet arrangement based on the comparison can be understood to mean that the at least one malfunction can be detected and displayed using the comparison or a comparison result. This means that the comparison result can be appropriately evaluated for detecting and displaying the malfunction and / or taken into account in a suitable calculation. The method can be carried out in particular for detecting a malfunction of a fuel outlet arrangement in a fuel cell system of a vehicle, in particular during operation of the fuel cell system in the vehicle. The method can in principle be carried out in any gas system. The term fuel can accordingly be understood generally as fluid or gas.

[0019] The method steps according to the invention do not have to be performed in the specified order. Individual method steps can also be performed in a different order and / or simultaneously. For example, it is possible to provide and / or calculate the reference backfill value first, and only then determine the actual backfill value.

[0020] If, for example, it is determined during the comparison that the determined backfill value is greater than the reference backfill value by a predefined value, a malfunction, in particular a clogged extraction filter, can be concluded. This means that the malfunction can be detected, for example, if it is recognized that the determined backfill value is greater than a predefined maximum permissible backfill value. During the comparison, for example, a difference between the reference backfill value and the determined backfill value can be calculated. The corresponding difference between the backfill values ​​can be compared with a predefined threshold value and / or a reference difference. If the difference is greater than the predefined threshold value or the reference difference, a malfunction as described above can be concluded.

[0021] In a method according to the invention, it is also possible for a pressure build-up gradient to be determined in the fuel line arrangement during start-up operation and for the backfilling value to be determined based on the pressure build-up gradient. The backfilling value can be determined easily and reliably using the pressure build-up gradient. Accordingly, an exceptionally high backfilling can be determined based on an excessive pressure increase in the fuel line arrangement after commissioning of the tank system or the fuel cell system. The pressure build-up gradient is preferably determined in a high-pressure line section of the fuel line arrangement. The pressure build-up gradient is preferably determined in each case by pressure measurements and a pressure evaluation of a line pressure in the fuel line arrangement over time.The pressure build-up gradient can therefore be determined using suitable measuring sensors and a computing unit that is in signal communication with the measuring sensors. The measuring sensors can have at least one pressure sensor for determining the pressure build-up gradient. The determined pressure build-up gradient can be compared with a provided and / or calculated target pressure build-up gradient, wherein the refilling value can be determined based on the comparison between the determined pressure build-up gradient and the provided target pressure build-up gradient. The comparison according to the invention between the determined pressure build-up gradient and the provided target pressure build-up gradient is carried out in particular when no pressure build-up is measured or detected in a medium-pressure line section of the fuel line arrangement in which the gas pressure is at least on average lower than in the high-pressure line section.no pressure build-up can be detected by measuring. In this way, the tightness of a pressure regulator in the fuel line arrangement can be checked to ensure that the mass flow through the respective outlet valve was effective solely for the pressure build-up in the high-pressure line section. The fact that the target pressure build-up gradient is provided can be understood to mean that the target pressure build-up gradient can be read from a memory and thus made available for comparison or can first be calculated and only then made available for comparison. This means that providing can also be understood to mean determining and / or calculating the target pressure build-up gradient and then making it available.

[0022] According to a further embodiment of the present invention, it is possible for the following steps to be carried out in a method:

[0023] - Determining a tank pressure in the respective fuel tank during start-up operation, - Determining a line pressure in the fuel line arrangement,

[0024] - Making comparisons between the tank pressure in the respective fuel tank and the line pressure, and

[0025] - Determine the backfill value based on the comparisons made.

[0026] In this way, backfilling and consequently the malfunction can be determined particularly reliably and / or the actual existence of a malfunction can be easily verified. If the determined pressure build-up gradient or the comparison with the target pressure build-up gradient described above indicates a malfunction, for example a clogged extraction filter, this can now be verified and clarified. In particular, it can be determined on which tank the possibly clogged extraction filter is located. However, such a determination and / or associated calculations only need to be carried out if there is reason to do so based on the detection of a possible malfunction described above. In other words, if the initial comparison does not reveal any indication of a malfunction, subsequent calculations to determine a more precise cause of the error can be dispensed with.In this way, the process can be carried out with low computing capacity and thus in a correspondingly energy-saving manner.

[0027] For further verification, the following steps are additionally or alternatively possible

[0028] - Determining a tank pressure in the respective fuel tank during start-up operation,

[0029] - Carrying out comparisons between the respective determined tank pressures in the fuel tanks, and

[0030] - Determine the backfill value based on the comparisons made.

[0031] In addition, the following steps are possible in addition or as an alternative:

[0032] - Determining the fuel level in the respective fuel tank during start-up operation,

[0033] - Carrying out comparisons between the respective determined fuel levels in the fuel tanks and determining the refill value based on the comparisons carried out.

[0034] In this way, the malfunction can also be identified, checked and specified particularly reliably.

[0035] In a method according to the invention, it is also possible for the outlet means to each have a removal filter, and for the malfunction to be detected with reference to a degree of clogging of a removal filter of at least one outlet means. This means that, based on the comparison according to the invention or on the basis of the comparison according to the invention, a malfunction can be detected, in particular, in that a clogged removal filter of an outlet means is identified. Accordingly, the malfunction can be understood as a degree of clogging of a removal filter of at least one outlet means that lies above a reference clogging degree or a predefined and / or predefinable maximum permissible clogging degree. If an excessively high clogging degree is identified, appropriate countermeasures can be initiated to take account of any problems that may result therefrom. In particular, operation of the fuel cell system orof the tank system, in which a fuel tank would not or could not be emptied as desired or would not be available to provide the fuel as desired.

[0036] A further aspect of the present invention relates to a tank system for a fuel cell system, comprising a plurality of fuel tanks, a fuel line arrangement for conducting fuel from the fuel tanks, and a fuel outlet arrangement with an outlet means for each fuel tank for the controlled conduction of fuel from the fuel tanks through the fuel line arrangement. The tank system further comprises a control unit for performing a start-up operation of the fuel cell system.an alternative gas system and thereby conducting fuel from the fuel tanks through the fuel line arrangement, a determination unit for determining a backfilling value relating to a backfilling of fuel via the fuel line arrangement into at least one fuel tank during start-up operation, and a computing unit for performing a comparison between the determined backfilling value during start-up operation and a provided reference backfilling value, as well as for detecting a malfunction of the fuel outlet arrangement based on the comparison. The tank system according to the invention thus offers the same advantages as those described in detail with reference to the method according to the invention.The target pressure build-up gradient described above can be calculated by a computing unit and / or read from a memory to perform the comparison with the determined pressure build-up gradient. The computing unit can be configured and designed to calculate the target pressure build-up gradient in the manner described above. The tank system can be configured and designed as part of a fuel cell system. The fuel cell system can be configured and designed as part of a vehicle.

[0037] The invention further proposes a tank system configured and designed to carry out a method as described above. This means that the tank system can have suitable sensors, a suitable computing unit, and / or suitable actuators for carrying out the method.

[0038] A further aspect of the invention relates to a computer program product comprising instructions that cause the method steps according to the invention to be executed in a tank system as described above. The invention also relates to a computer-readable, in particular non-volatile, storage medium on which such a computer program product is stored. Thus, the computer program product according to the invention and the storage medium also provide the advantages described above.

[0039] The computer program product can be implemented as computer-readable instruction code in any suitable programming language and / or machine language, such as JAVA, C++, C#, and / or Python. The computer program product can be stored on a computer-readable storage medium, such as a data disk, a removable drive, a volatile or non-volatile memory, or a built-in memory / processor. The instruction code can program a computer or other programmable devices, such as a control unit of the fuel cell system and / or a vehicle with the fuel cell system, to perform the desired functions. Furthermore, the computer program product can be provided and / or be provided on a network, such as the Internet, from which it can be downloaded by a user as needed.The computer program product can be and / or be implemented by means of software as well as by means of one or more special electronic circuits, i.e. in hardware or in any hybrid form, i.e. by means of software components and hardware components.

[0040] Further measures improving the invention will become apparent from the following description of various exemplary embodiments of the invention, which are schematically illustrated in the figures. All features and / or advantages apparent from the claims, the description, or the figures, including structural details and spatial arrangements, may be essential to the invention both individually and in various combinations.

[0041] They show schematically:

[0042] Figure 1 shows a fuel cell system with a tank system according to an embodiment of the present invention,

[0043] Figure 2 shows a tank system according to an embodiment of the present invention,

[0044] Figure 3 shows storage means with a computer program product stored thereon according to an embodiment of the present invention, and Figure 4 shows a flowchart for explaining a method according to an embodiment of the present invention.

[0045] Elements with the same function and mode of operation are provided with the same reference symbols in the figures.

[0046] Fig. 1 shows a fuel cell system 10 configured and designed for mobile use in a vehicle. The fuel cell system 10 has a filling section 30 with a tank connection 35 in the form of a connecting piece. The fuel cell system 10 further has a storage section 31 with a fuel line arrangement 15, a fuel tank arrangement 38, and a valve 36 in the form of a shut-off or blocking valve. In addition, the fuel cell system 10 has a supply section 32 with a pressure regulator 37, through which the fuel from the storage section 31 can be fed in a controlled manner into a fuel cell section 33 of the fuel cell system 10. In addition, the fuel cell system 10 has a power section 34, in which the current or voltage generated in the fuel cell section 10 can be converted into drive power for the vehicle.

[0047] Fig. 2 shows a tank system 11 for a fuel cell system 10 as shown in Fig. 1. The tank system 11 shown in Fig. 2 has three fuel tanks 12, 13, 14, a fuel line arrangement 15 for conducting fuel from the fuel tanks 12, 13, 14, and a fuel outlet arrangement 16 for the controlled conduction of fuel from the fuel tanks 12, 13, 14 through the fuel line arrangement 15. The fuel tanks 12, 13, 14 are connected parallel to one another on the fuel line arrangement 15. The fuel outlet arrangement 16 has three outlet means 17, 18, 19, with one outlet means 17, 18, 19 being installed on each fuel tank 12, 13, 14. Each outlet means 17, 18, 19 has an outlet valve and a removal filter (not shown in detail). Furthermore, a pressure sensor 25 is provided in each tank for determining a gas pressure in the respective fuel tank 12, 13, 14.The tank system 11 also has a control unit 20 for performing a start-up operation of the fuel cell system 10 and, in doing so, for conducting fuel from the fuel tanks 12, 13, 14 through or into the fuel line arrangement 15. The control unit 20 is shown schematically and can have several spaced-apart components. The control unit 20 can have a control unit, in particular in the form of a vehicle control unit.

[0048] In addition, the tank system 11 has a determination unit 21 for determining a backfilling value with respect to a backfilling of fuel via the fuel line arrangement 15 into at least one fuel tank 12, 13,

[0049] 14 during start-up operation. The determination unit 21 has a further pressure sensor for determining a line pressure and in particular for determining a pressure build-up gradient in the fuel line arrangement

[0050] 15 during start-up operation at a predefined time after the electrical activation of the outlet means.

[0051] According to the embodiment shown in Fig. 2, a component of the control unit 20 is a computing unit 22 for performing a comparison between the determined backfilling value during startup operation and a provided reference backfilling value, and for detecting a malfunction of the fuel outlet arrangement 16 based on the comparison. The computing unit 22 can further be configured to perform a comparison between the determined pressure buildup gradient during startup operation and the provided target pressure buildup gradient to determine the backfilling value.

[0052] Fig. 3 shows a computer-readable, non-volatile storage medium 24 in the form of a memory stick. A computer program product 23 is stored on the storage medium 24. The computer program product 23 includes instructions that cause a method to be executed in the tank system 11 shown in Figs. 1 and 2, which method will be explained below with reference to Fig. 4.

[0053] With reference to the flow chart shown in Fig. 4, a method for detecting a malfunction of the fuel outlet arrangement 16 described above is explained. More precisely, the method can be used to find out whether or not the fuel outlet arrangement 16 has a malfunction, in particular in the form of at least one clogged extraction filter. For this purpose, in a step S1, a start-up operation of the fuel cell system 10 is carried out, wherein fuel from the fuel tanks 12, 13, 14 is conducted through or into the fuel line arrangement 15. In a second step S2, a backfilling value relating to a backfilling of fuel via the fuel line arrangement 15 into at least one fuel tank 12, 13, 14 during the start-up operation is determined. For this purpose, a pressure build-up gradient is determined in the fuel line arrangement 15 by means of the determination device 21 during the start-up operation, wherein the backfilling value ora corresponding backfilling level is determined based on the determined pressure build-up gradient. In a third step S3, which does not necessarily have to be carried out after the second step S2, a reference backfilling value is provided. In a fourth step S4, a comparison is carried out between the determined backfilling value during start-up operation and the provided reference backfilling value. In a fifth step S5, based on the comparison, a malfunction of the fuel outlet arrangement 16 is carried out and specified or displayed as a corresponding error signal. In other words, based on the comparison, a conclusion is drawn as to whether or not a malfunction, in particular in the form of at least one clogged extraction filter, exists in the fuel outlet arrangement 16.

[0054] In addition to the illustrated embodiments, the invention permits further design principles. This means that the invention should not be considered limited to the exemplary embodiments explained with reference to the figures. In particular, the pressure sensors 25 in the respective fuel tanks 12, 13, 14 could be omitted. If the pressure sensors 25 are present, the following steps can be performed to detect the malfunction: determining a tank pressure in the respective fuel tank 12, 13, 14 during start-up operation, determining a line pressure in the fuel line arrangement 15, performing comparisons between the tank pressure in the respective fuel tank 12, 13, 14 and the line pressure, and determining the backfill value based on the comparisons performed.Alternatively or additionally, the following steps can be performed: determining a tank pressure in the respective fuel tank during start-up operation, performing comparisons between the respectively determined tank pressures in the fuel tanks, and determining the backfill value based on the comparisons performed. Furthermore, the following steps could be performed alternatively or additionally: determining a fuel level in the respective fuel tank during start-up operation, performing comparisons between the respectively determined fuel levels in the fuel tanks, and determining the backfill value based on the comparisons performed.

Claims

Claims 1 . Method for detecting a malfunction of a Fuel outlet arrangement (16) in a tank system (11), in particular for a fuel cell system (10), wherein the tank system (11) comprises a plurality of fuel tanks (12, 13, 14), a fuel line arrangement (15) for conducting fuel from the fuel tanks (12, 13, 14) and a fuel outlet arrangement (16) each having an outlet means (17, 18, 19) for each fuel tank (12, 13, 14) for the controlled conduction of fuel from the fuel tanks (12, 13, 14) through the fuel line arrangement (15), characterized by: - carrying out a starting operation and thereby conducting fuel from the fuel tanks (12, 13, 14) through the fuel line arrangement (15), - determining a backfilling value relating to a backfilling of fuel via the fuel line arrangement (15) into at least one fuel tank (12, 13, 14) during the starting operation, - Providing a reference refill value, - performing a comparison between the determined backfill value during start-up operation and the provided reference backfill value, and - detecting a malfunction of the fuel outlet assembly (16) based on the comparison.

2. Method according to claim 1, characterized in that during the starting operation a pressure build-up gradient in the fuel line arrangement (15) is determined and the refilling value is determined based on the pressure build-up gradient. Method according to one of the preceding claims, characterized by: - Determining a tank pressure in the respective fuel tank (12, 13, 14) during starting operation, - determining a line pressure in the fuel line arrangement (15), - performing comparisons between the tank pressure in the respective fuel tank (12, 13, 14) and the line pressure, and - Determining the backfill value based on the comparisons performed. Method according to one of the preceding claims, characterized by: - Determining a tank pressure in the respective fuel tank (12, 13, 14) during starting operation, - performing comparisons between the respective determined tank pressures in the fuel tanks (12, 13, 14), and - Determining the backfill value based on the comparisons performed. Method according to one of the preceding claims, characterized by: - Determining a fuel level in the respective fuel tank (12, 13, 14) during starting operation, - performing comparisons between the respective determined fuel levels in the fuel tanks (12, 13, 14), and - Determining the backfill value based on the comparisons performed. Method according to one of the preceding claims, characterized in that the outlet means (17, 18, 19) each have a removal filter, and the malfunction is detected with reference to a degree of clogging of a removal filter of at least one outlet means (17, 18, 19). Tank system (11) for a fuel cell system (10), comprising a plurality of fuel tanks (12, 13, 14), a fuel line arrangement (15) for conducting fuel from the fuel tanks (12, 13, 14) and a fuel outlet arrangement (16) with an outlet means (17, 18, 19) for each fuel tank (12, 13, 14) for the controlled conduction of fuel from the fuel tanks (12, 13, 14) through the fuel line arrangement (15), characterized by: - a control unit (20) for carrying out a starting operation of the fuel cell system (10) and thereby conducting fuel from the fuel tanks (12, 13, 14) through the fuel line arrangement (15), - a determination unit (21) for determining a backfilling value relating to a backfilling of fuel via the fuel line arrangement (15) into at least one fuel tank (12, 13, 14) during the starting operation, and - a computing unit (22) for performing a comparison between the determined refilling value during start-up operation and a provided reference refilling value, and for detecting a malfunction of the fuel outlet arrangement (16) based on the comparison. Tank system (11) according to claim 7, which is configured and designed to perform a method according to one of claims 1 to 6. A computer program product (23) comprising instructions that cause the method steps according to one of claims 1 to 6 to be executed in the tank system (11) according to one of claims 7 to 8. A computer-readable storage medium (24) having a computer program product according to claim 9 stored thereon.

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