Tank system and method for checking a tank system comprising a plurality of high-pressure tanks by temporarily withdrawing gas from a single tank vessel
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2024-07-31
- Publication Date
- 2026-06-24
Smart Images
Figure EP2024071637_20022025_PF_FP_ABST
Abstract
Description
[0001] Description
[0002] title
[0003] Tank system and method for testing a tank system with multiple high-pressure tanks by temporarily withdrawing gas from only one tank container
[0004] The presented invention relates to a method for checking a tank system, in particular a temperature sensor and a switching state of respective tank valves in a tank system with several high-pressure tanks and a tank system.
[0005] State of the art
[0006] High-pressure tank systems, especially in the automotive sector, often comprise multiple high-pressure tanks for storing fluids such as hydrogen. For safety reasons, each of these high-pressure tanks is assigned a temperature sensor that measures the temperature within the high-pressure tank.
[0007] Due to thermal and / or mechanical stress, a temperature sensor may provide incorrect values, which may lead to errors in subsequent processing based on the incorrect values.
[0008] Disclosure of the invention
[0009] Within the scope of the invention presented, a method for testing a tank system with multiple high-pressure tanks and a tank system are presented. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the method according to the invention naturally also apply in connection with the tank system according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.
[0010] The invention presented serves in particular to verify the plausibility of temperature values determined by a temperature sensor in a tank system or to detect a faulty temperature sensor as well as to verify the plausibility of or detect the switching states of respective tank valves.
[0011] Thus, according to a first aspect of the invention presented, a method for checking a tank system, in particular a temperature sensor and switching states of respective tank valves of the tank system, with a plurality of high-pressure tanks is presented.
[0012] The presented method comprises operating a consumer for fluid stored in the high-pressure tanks, storing pressure values determined by a system pressure sensor in a high-pressure system of the tank system, closing tank valves of all high-pressure tanks with the exception of one tank valve of a first high-pressure tank, determining temperature values by each temperature sensor of the tank system, opening all other tank valves assigned to other high-pressure tanks so that the first high-pressure tank is refilled, determining temperature values by each temperature sensor of the tank system, and checking the plausibility of the temperature sensors as soon as or after pressure equalization in the high-pressure system of the tank system has been determined by the arranged system pressure sensor.
[0013] The plausibility check comprises comparing first temperature values determined by the first temperature sensor assigned to the first high-pressure tank with predetermined first reference values, wherein the first temperature values are determined starting from a start time at which the tank valves of the high-pressure tanks were closed up to an end time at which the pressure difference initially lies below the plausibility check threshold value, comparing further temperature values determined by the further temperature sensors assigned to the further high-pressure tanks with predetermined further reference values, wherein the further temperature values are determined starting from a start time at which the tank valves were opened up to an end time at which the values determined by the system pressure sensor first indicate pressure equalization, ie in particular the pressure difference initially oris below the plausibility threshold for the first time, the output of a message which identifies values determined by the first temperature sensor as plausible in the event that a first temperature difference between the first temperature values and the first reference values is less than or equal to a first diagnostic threshold, or the output of a message which identifies respective values determined by a further temperature sensor as plausible in the event that a further temperature difference between further temperature values determined by the further temperature sensor and the further reference values is less than or equal to a further diagnostic threshold.
[0014] In the context of the invention presented, outputting a message is understood to mean a process in which a message, such as a text or a so-called "flag," is displayed on an output unit, such as a display, and / or stored in a memory, such as an error memory or a working memory. Accordingly, by outputting a message that identifies values determined by a temperature sensor as plausible, another or external function can obtain information about whether the values determined by the temperature sensor are plausible and can process them further or exclude them from further processing.
[0015] The presented method is carried out during the operation of a consumer, such as a fuel cell system, so that fluid is continuously drained or removed from the high-pressure tanks of the tank system.
[0016] To verify the plausibility of the values determined by a temperature sensor, a high-pressure tank assigned to the temperature sensor to be tested is first at least partially emptied by introducing gas or fluid from the high-pressure tank into the respective lines or the high-pressure area of the tank system. All other high-pressure tanks are closed, creating a pressure difference between the first high-pressure tank and the other high-pressure tanks.
[0017] As soon as the pressure difference has reached a predetermined threshold or a high-pressure range, whereby a system pressure in a pipe system in the flow direction after the high-pressure tanks corresponds to the pressure in the opened first high-pressure tank, temperature values are determined by the temperature sensors assigned to the respective high-pressure tanks.
[0018] Subsequently, all tank valves of all high-pressure tanks are opened so that a passive gas backfilling from the previously unopened other high-pressure tanks into the first high-pressure tank is started due to the different pressure levels.
[0019] As soon as a quasi-steady state is reached, in which the pressure values determined by the system pressure sensor after the tank valves of all high-pressure tanks are constant or equalized, temperature values are again determined by the temperature sensors assigned to the respective high-pressure tanks. Optionally, pressure values are also determined by the pressure sensors assigned to the respective high-pressure tanks.
[0020] The temperature sensors are then checked for plausibility based on the measured temperature and / or pressure values. For this purpose, reference values are selected, which are compared with the measured temperature values. If, during the comparison, a temperature difference between the temperature values measured by a respective additional temperature sensor and the corresponding reference values is less than or equal to a diagnostic threshold, a message is issued indicating that the respective values measured by the temperature sensor are plausible.
[0021] Accordingly, if during the comparison a temperature difference between temperature values determined by a respective additional temperature sensor and corresponding reference values is greater than the diagnostic threshold, a message is issued which marks the respective values determined by the temperature sensor as implausible or not plausible.
[0022] It can be provided that the first reference values are selected as a function of pressure values determined by a pressure sensor, in particular a first pressure sensor assigned to the first high-pressure tank.
[0023] The respective plausibility check is performed by comparing the measured temperature changes, for example, with temperature changes stored in a memory or with calculated or expected temperature changes. For this purpose, corresponding reference values are stored, for example, in the form of an assignment scheme for the respective pressure changes or pressures and the ambient and gas temperatures. Alternatively, a comparison is made between individual tank temperature reductions in the tanks closed during the process from the time all tank valves are opened until pressure equalization is achieved.
[0024] It can further be provided that the further reference values are selected as a function of pressure values determined by a pressure sensor, in particular a further pressure sensor assigned to a respective further high-pressure tank.
[0025] Specific reference values stored for each high-pressure tank allow for particularly precise checking of a corresponding temperature sensor.
[0026] It may further be provided that the first reference values and the further reference values are selected depending on a type of a respective high-pressure tank.
[0027] Taking into account the type of a respective high-pressure tank, its specific properties, such as its thermal conductivity, can be taken into account when verifying the plausibility of a respective temperature sensor or corresponding temperature values. It can also be provided that a history of temperature values determined by a respective additional temperature sensor is compared with a number of diagnostic values, with the number of diagnostic values being determined based on the additional temperature values determined by all additional temperature sensors.
[0028] By comparing the temperature values determined by a respective temperature sensor with diagnostic values determined based on the temperature values determined by all other temperature sensors, the respective temperature sensor or the temperature value determined by it can be verified for plausibility based on all other or other temperature sensors. Accordingly, the other temperature sensors are used as a reference or plausibility criterion for a respective temperature sensor to be verified.
[0029] It may further be provided that the number of diagnostic values corresponds to an average of the additional temperature values determined by all additional temperature sensors.
[0030] In particular, temperature values determined by the additional temperature sensors can be transformed into diagnostic values using a mathematical method, such as averaging.
[0031] It can further be provided that, in the event that a difference between the course of temperature values determined by a respective further temperature sensor and the number of diagnostic values is greater than a diagnostic threshold value, a characteristic curve stored in a memory and assigned to the further temperature sensor is adapted in such a way that the difference between the course of temperature values determined by a respective further temperature sensor and the number of diagnostic values is less than or equal to the diagnostic threshold value.
[0032] By adapting a characteristic curve stored in a memory, e.g. of a control unit, and assigned to a respective temperature sensor, a possibly faulty temperature sensor can be corrected, e.g. with regard to a sensor drift, so that the temperature sensor again provides plausible temperature values.
[0033] It can further be provided that, in the event that, after all other high-pressure tanks have been opened, temperature values determined by at least one temperature sensor, in particular a temperature sensor in an area downstream of the high-pressure tanks in the flow direction, fall, a message is output indicating that the corresponding tank valves of the high-pressure tanks have been opened.
[0034] Since the outflow of fluid from the respective high-pressure tanks into the high-pressure area leads to a temperature drop in the respective high-pressure tank, it can be assumed that if such a temperature drop is detected, the high-pressure tanks or their tank valves are open. Accordingly, the opening or open state of the tank valves can be verified based on the temperature drop in the high-pressure tank.
[0035] According to a second aspect, the presented invention relates to a tank system for storing fluid.
[0036] The presented tank system comprises a first high-pressure tank, a number of further high-pressure tanks, a high-pressure system, a system pressure sensor arranged in the high-pressure system, a first temperature sensor configured to measure a temperature in the first high-pressure tank, a number of further temperature sensors each configured to measure a temperature in a respective further high-pressure tank, and a computing unit.
[0037] The computing unit is configured to carry out a possible embodiment of the proposed method. It can be provided that the computing unit is configured to, during operation of a consumer for fluid stored in the high-pressure tanks:
[0038] To close tank valves of all high-pressure tanks with the exception of one tank valve of a first high-pressure tank, To determine temperature values by each temperature sensor of the tank system, To open all other tank valves assigned to other high-pressure tanks so that the first high-pressure tank is refilled, To check the plausibility of temperature values to be determined again by each temperature sensor of the tank system as soon as or after a pressure equalization that has taken place in the high-pressure system of the tank system has been determined by the system pressure sensor arranged in the high-pressure system of the tank system, in particular the determined pressure values are constant, wherein the plausibility check comprises:
[0039] Comparing first temperature values determined by the first temperature sensor assigned to the first high-pressure tank with predetermined first reference values, wherein the first temperature values are determined starting from a starting time at which the tank valves of the high-pressure tanks were closed up to an end time at which values determined by the system pressure sensor first indicate pressure equalization, in particular are constant, Comparing further temperature values determined by the further temperature sensors assigned to the further high-pressure tank with predetermined further reference values, wherein the further temperature values are determined starting from a starting time at which the tank valves of the high-pressure tanks were opened up to an end time at which values determined by the system pressure sensor first indicate pressure equalization, in particular are constant,
[0040] Outputting a message that identifies values determined by the first temperature sensor as plausible in the event that a first temperature difference between the first temperature values and the first reference values is less than or equal to a first diagnostic threshold,
[0041] Outputting a message that identifies respective values determined by a further temperature sensor as plausible in the event that a further temperature difference between further temperature values determined by a respective further temperature sensor and the further reference values is less than or equal to a further diagnostic threshold value.
[0042] It can further be provided that the computing unit is configured to successively check each temperature sensor of the tank system as the first temperature sensor.
[0043] In the context of the invention presented, a computing unit is understood to mean a computer, a processor, a subprocessor, a control unit or any other programmable circuit.
[0044] Advantages described in detail for the method for testing a tank system according to the first aspect of the invention apply equally to the tank system for storing fluid according to the second aspect of the invention.
[0045] Further advantages, features, and details of the invention will become apparent from the following description, which describes exemplary embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination.
[0046] drawing
[0047] They show:
[0048] Figure 1 shows a possible design of the presented procedure,
[0049] Figure 2 shows a possible design of the tank system presented, Figure 3 shows a pressure / temperature / time diagram, which shows time on its abscissa and pressure and temperature on its ordinate.
[0050] Description of the embodiments
[0051] Figure 1 shows a method 100 for checking a tank system with multiple high-pressure tanks
[0052] The method 100 comprises an operating step 101 in which a consumer for fluid stored in the high-pressure tanks is operated or such operation is requested.
[0053] Furthermore, the method 100 comprises a closing step 103 in which tank valves of all high-pressure tanks are closed with the exception of one tank valve of a first high-pressure tank, a first determination step 105 in which, after the closing step 103, temperature values are determined by each temperature sensor of the tank system, an opening step 107 in which all further tank valves assigned to further high-pressure tanks are opened so that the first high-pressure tank is refilled, and a second determination step 109 in which temperature values are determined by each temperature sensor of the tank system.
[0054] Furthermore, the method 100 comprises a plausibility check step 111 in which the temperature sensors or temperature values determined by the temperature sensors are checked for plausibility as soon as pressure values determined by a system pressure sensor arranged in a high-pressure system of the tank system indicate pressure equalization.
[0055] The plausibility check step 111 comprises a first comparison step 113 in which first temperature values determined by the first temperature sensor assigned to the first high-pressure tank are compared with predetermined first reference values, wherein the first temperature values are or were determined starting from a start time at which tank valves of the high-pressure tanks were closed up to an end time at which the values determined by the system pressure sensor indicate pressure equalization, in particular are constant for the first time.
[0056] Furthermore, the plausibility check step 111 comprises a second comparison step 115, in which further temperature values determined by further temperature sensors assigned to the further high-pressure tank are compared with predetermined further reference values, wherein the further temperature values are or were determined starting from a start time at which tank valves of the high-pressure tanks were opened up to an end time at which values determined by the system pressure sensor first indicate pressure equalization, in particular are constant.
[0057] Furthermore, the plausibility check step 111 comprises a first output step 117 in which a message identifying values determined by the first temperature sensor 213 as plausible is output in the event that a first temperature difference between the first temperature values and the first reference values is less than or equal to a first diagnostic threshold value.
[0058] Furthermore, the plausibility check step 111 comprises a second output step 119, in which a message which identifies respective values determined by a further temperature sensor as plausible is output in the event that a further temperature difference between further temperature values determined by a respective further temperature sensor and the further reference values is less than or equal to a further diagnostic threshold value.
[0059] Figure 2 shows a tank system 200. The tank system 200 comprises a first high-pressure tank 201, a number of further high-pressure tanks 203, a high-pressure system 205, a system pressure sensor 209 arranged in the high-pressure system 205, a first temperature sensor 213 which is configured to measure a temperature in the first high-pressure tank 201, a number of further temperature sensors 215, each of which is configured to measure a temperature in a respective further high-pressure tank 203, and a computing unit 211, wherein the computing unit 211 is configured to carry out the method 100 according to Figure 1. The computing unit 211 is configured in particular to control, i.e., to open or close, further tank valves 217 of the further high-pressure tanks 203 and a first tank valve 219 of the first high-pressure tank 201.
[0060] Figure 3 shows a diagram 300 which represents time on its abscissa and pressure and temperature on its ordinate.
[0061] A curve 301 corresponds to a pressure in all high-pressure tanks starting from a starting time T0 up to a time T1, at which gas is extracted from all high-pressure tanks until T1. From time T1 onward, gas is extracted only from the first high-pressure tank 201, resulting in a first curve 303 of a pressure in the first high-pressure tank and a further curve 305 of a pressure in the other high-pressure tanks.
[0062] At time T2, the additional high-pressure tanks are also opened, so that the additional curve 305 and the first curve 303 approach each other and transition to a balanced state at time T3. Accordingly, the first curve 303 increases after time T2, and the additional curve 305 decreases after time T2, as gas flows from the additional high-pressure tanks into the first high-pressure tank, refilling it.
[0063] A curve 307 corresponds to first temperature values determined with a temperature sensor assigned to the first high-pressure tank.
[0064] Curves 309 and 311 each correspond to further temperature values determined with further temperature sensors assigned to further high-pressure tanks.
[0065] At time T1, gas only exits the first high-pressure tank, so that due to the corresponding pressure drop in the first high-pressure tank, the temperature in the first high-pressure tank drops, as can be seen by curve 307. Due to the refilling from time T2, gas flows back into the first high-pressure tank, so that the temperature in the first high-pressure tank rises again, while the temperature in the other high-pressure tanks decreases, as can be seen by curves 309 and 311.
[0066] The curves 307, 309 and 311 approach each other at time T3 until a balanced pressure state is reached.
[0067] Accordingly, the temperature sensor assigned to the first high-pressure tank can be checked using the characteristic curve 307, or the temperature values determined by this temperature sensor can be checked for plausibility. For this purpose, for example, the curve 307 or its values can be stored as reference values in a memory of a control unit. By comparing temperature values determined by the temperature sensor with the reference values, a deviation between the determined temperature values and the reference values can be determined or quantified. For this purpose, for example, an average difference between the determined temperature values and the reference values can be formed. In the event that the deviation between the determined temperature values and the reference values is greater than a diagnostic threshold, it can be assumed that the determined temperature values are not plausible.Accordingly, a message can be issued that marks the determined temperature values and / or the corresponding temperature sensor as implausible.
Claims
Claims 1. A method (100) for testing a tank system (200) having a plurality of high-pressure tanks (201, 203), the method (100) comprising: Operating (101) a consumer of fluid stored in the high-pressure tanks (201, 203), Closing (103) tank valves (217) of all high-pressure tanks (203) with the exception of a tank valve (219) of a first high-pressure tank (201), determining (105) temperature values by each temperature sensor (213, 215) of the tank system (200), Opening (107) of all further tank valves (217) associated with all further high-pressure tanks (203) so that the first high-pressure tank (201) is refilled, Determining (109) temperature values by each temperature sensor (213, 215) of the tank system (200) and checking the plausibility (111) of the temperature sensors (213, 215) as soon as or after a pressure equalization in the high-pressure system (205) of the tank system (200) has been determined by the arranged system pressure sensor (209), wherein the checking the plausibility (111) comprises: Comparing (113) first temperature values determined by the first temperature sensor (213) assigned to the first high-pressure tank (201) with predetermined first reference values, wherein the first temperature values are determined starting from a (T1) start time at which the tank valves (217) of the high-pressure tanks (203) were closed, up to an end time (T3) at which the values determined by the system pressure sensor (209) first indicate pressure equalization, Comparing (115) further temperature values determined by the further temperature sensors (215) assigned to the further high-pressure tanks (203) with predetermined further reference values, wherein the further temperature values are determined starting from a starting time (T2) at which the tank valves (217) of the high-pressure tanks (203) were opened, up to an end time at which values determined by the system pressure sensor (209) first indicate pressure equalization, Outputting (117) a message which identifies values determined by the first temperature sensor (213) as plausible in the event that a first temperature difference between the first temperature values and the first reference values is less than or equal to a first diagnostic threshold value, Outputting (119) a message which identifies respective values determined by a further temperature sensor (215) as plausible in the event that a further temperature difference between further temperature values determined by a respective further temperature sensor (215) and the further reference values is less than or equal to a further diagnostic threshold value.
2. Method (100) according to claim 1, characterized in that the first reference values are selected as a function of pressure values determined by a pressure sensor (209).
3. Method (100) according to claim 1 or 2, characterized in that the further reference values are selected as a function of pressure values determined by a pressure sensor (209).
4. Method (100) according to claim 2 or 3, characterized in that the first reference values and the further reference values are selected depending on a type of a respective high-pressure tank (201, 203).
5. Method (100) according to one of the preceding claims, characterized in that that a curve (309, 311) of temperature values determined by a respective further temperature sensor is compared with a number of diagnostic values, wherein the number of diagnostic values is determined on the basis of further temperature values determined by all further temperature sensors (215).
6. The method (100) according to claim 5, characterized in that the number of diagnostic values corresponds to an average of further temperature values determined by all further temperature sensors (215).
7. Method (100) according to claim 5 or 6, characterized in that in the event that a difference between the course (309, 311) of temperature values which were determined by a respective further temperature sensor (215) and the number of diagnostic values is greater than a diagnostic threshold value, a characteristic curve stored in a memory and assigned to the further temperature sensor (215) is adapted such that the difference between the course of temperature values which were determined by a respective further temperature sensor (215) and the number of diagnostic values is less than or equal to the diagnostic threshold value.
8. Method (100) according to one of the preceding claims, characterized in that in the event that, after the opening of all further high-pressure tanks (203), temperature values determined by at least one temperature sensor (215) decrease, a message is output which indicates an opening of corresponding tank valves (217) of the high-pressure tanks (203).
9. Tank system (200) for storing fluid, the tank system (200) comprising: a first high-pressure tank (201), a number of further high-pressure tanks (203), a high-pressure system (205), a system pressure sensor (209) arranged in the high-pressure system (205), a first temperature sensor (213) configured to measure a temperature in the first high-pressure tank (201), a number of further temperature sensors (215), each configured to measure a temperature in a respective further high-pressure tank (203), a computing unit (211), wherein the computing unit (211) is configured to carry out a method (100) according to one of claims 1 to 8.
10. Tank system (200) according to claim 9, characterized in that the computing unit (211) is configured to, during operation of a consumer for fluid stored in the high-pressure tanks (201, 203): to close tank valves (217) of all high-pressure tanks (203) with the exception of one tank valve (219) of a first high-pressure tank (201), to determine temperature values by each temperature sensor (213, 215) of the tank system (200), to open all further tank valves (217) associated with further high-pressure tanks (203) so that the first high-pressure tank (201) is refilled, to check the plausibility of temperature values to be determined by each temperature sensor (213, 215) of the tank system (200) as soon as or after a pressure equalization in the high-pressure system (205) of the tank system (200) has been determined by the arranged system pressure sensor (209), wherein the plausibility check comprises: Comparing (113) first temperature values determined by the first temperature sensor (213) associated with the first high-pressure tank (201) with predetermined first reference values, wherein the first temperature values are determined starting from a start time (T1) at which the tank valves (217) of the high-pressure tanks (203) were closed, up to an end time (T3) at which values determined by the system pressure sensor (209) first indicate pressure equalization, Comparing (115) further temperature values determined by further temperature sensors (215) assigned to the further high-pressure tank (203) with predetermined further reference values, wherein the further temperature values are determined starting from a starting time (T2) at which the tank valves (217) of the high-pressure tanks (203) were opened, up to an end time at which values determined by the system pressure sensor (209) first indicate pressure equalization, Outputting (117) a message which identifies values determined by the first temperature sensor (213) as plausible in the event that a first temperature difference between the first temperature values and the first reference values is less than or equal to a first diagnostic threshold value, Outputting (119) a message which identifies respective values determined by a further temperature sensor (215) as plausible in the event that a further temperature difference between further temperature values determined by a respective further temperature sensor (215) and the further reference values is less than or equal to a further diagnostic threshold value.
11. Tank system (200) according to claim 9 or 10, characterized in that the computing unit (211) is configured to successively check each temperature sensor (213, 215) of the tank system (200) as a first temperature sensor.