Tank control unit of a hydrogen storage system, hydrogen storage system with tank control unit and associated method

Description

[0001] The invention relates to a tank control unit of a hydrogen storage device for a fuel cell system, a hydrogen storage device with such a tank control unit and an associated method.

[0002] Hydrogen storage systems and associated tank control units are already known in the state of the art, but these are usually only designed to control the pressures and temperatures during a refueling process of the hydrogen storage system and the pressures and temperatures in the hydrogen storage system itself as well as the volume flow of hydrogen into and out of the hydrogen storage system.

[0003] However, due to the sometimes poor quality of the hydrogen supplied or stored in the hydrogen storage, pollutants or harmful gases can be introduced into the hydrogen storage and then transported, for example, into a fuel cell, which can damage the hydrogen storage itself or a fuel cell supplied with hydrogen by the hydrogen storage.

[0004] Tank control units for hydrogen storage or aspects of such tank control units are disclosed in the prior art, for example, by the documents DE 10 2012 010 174 A1, JP 2014 122 694 A, JP 2019 102 288 A, JP 2003 130 291 A, KR 10 2014 0142404 A and US 5 794 666 A.

[0005] The invention is therefore based on the object of overcoming the aforementioned disadvantages and enabling pollutant detection in and on the hydrogen storage device, so that, depending on the pollutant detection, a refueling process, a transport of the hydrogen to a fuel cell system and the hydrogen storage device itself can be controlled and protected from damage.

[0006] This problem is solved by the combination of features according to patent claim 1.

[0007] According to the invention, a tank control unit of a hydrogen storage device for a fuel cell system is proposed according to the features of the main claim. At least according to the first aspect of the invention, the hydrogen storage device itself is not part of the tank control unit, although components of the tank control unit can be integrated into the hydrogen storage device or into a hydrogen storage system comprising the hydrogen storage device. The tank control unit has an evaluation unit and at least one measuring device for detecting predetermined components, and in particular pollutants, of hydrogen stored in the hydrogen storage device and / or flowing into and / or flowing out of the hydrogen storage device. The hydrogen storage device can also have several tanks for storing the hydrogen, which are interconnected to form the hydrogen storage device.If this is the case, one measuring device can be provided for each tank or one measuring device for all tanks together. The components that can be detected by the measuring device are the harmful gases or general pollutants in the hydrogen, so that the measuring device can also be referred to as a pollutant measuring device. Such components or pollutants or gases can be, for example, carbon monoxide (CO), sulfur species (hydrogen sulfide H 2 S, carbonyl sulfide COS), halogen compounds (chloromethane H 3 CCl, trichloromethane HCCl 3 ), hydrocarbons (toluene C 7 H 8 ), formic acid (HCOOH), formaldehyde (HCHO) and mixtures, some of which contain nitrogen or oxygen.Accordingly, for example, a pollutant measuring device can be designed to detect several of the pollutants or a specific pollutant, so that one or more pollutant measuring devices can be provided in order to be able to determine the proportions of the predetermined components or pollutants. In order to process or report the measured values ​​of the pollutant measuring device(s), the evaluation unit has a communication interface and is designed to determine a proportion or concentration of pollutants or gases in the hydrogen from the components (pollutants) of the hydrogen detected by the at least one measuring device, to compare the proportion of pollutants with a predetermined limit value and to send a reporting signal via the communication interface if the proportion of pollutants in the hydrogen is exceeded.The reporting signal can, for example, be sent to a higher-level system or other control units.

[0008] In addition, the tank control unit can perform further functions in controlling the hydrogen storage and / or controlling a refueling process when refueling the hydrogen storage.

[0009] The tank control unit can, for example, have valves for pressure reduction in the hydrogen storage or a device for pressure reduction, a device for level monitoring of the hydrogen storage, measuring devices for determining and based thereon monitoring the temperature and pressure in the hydrogen storage and / or switching devices with associated valves for safety shutdown and emptying of the hydrogen storage in an emergency, such as an accident.

[0010] It is further possible for the tank control unit to have at least one additional pollutant measuring device for determining and monitoring the pollutants in the hydrogen or the proportions of the pollutants in the hydrogen in a hydrogen system of the fuel cell system through which hydrogen flows.

[0011] Furthermore, the tank control unit can monitor the hydrogen quality during a refueling process of the hydrogen storage tank. If the parameters of the hydrogen supplied to the hydrogen storage tank during the refueling process, which determine the hydrogen quality and include the proportion of pollutants in the hydrogen, are outside specified limits, this can be detected by the tank control unit and the refueling or filling process can be controlled and, in particular, stopped.

[0012] In addition, the control of the hydrogen storage system can be influenced by the measured values ​​of the pollutants obtained by the tank control unit or the concentrations of pollutants in the hydrogen determined from them, so that, for example, a flushing process, which can also be referred to as "purging", can be initiated specifically when limit values ​​are exceeded, so that harmful gases are diverted from the hydrogen storage system to protect the hydrogen storage system and, in particular, to protect the fuel cells of the fuel cell system.

[0013] The tank control unit can also take over communication with the petrol station or a tank system during the refueling process via the integrated communication interface.

[0014] As previously mentioned, the tank control unit can monitor a single tank of a hydrogen storage facility or multiple tanks of a hydrogen storage facility.

[0015] The tank control unit thus forms a scalable solution for monitoring / controlling / regulating hydrogen, which can also be made dependent on the size of the hydrogen storage facility or the number of tanks the hydrogen storage facility comprises.

[0016] The solution according to the invention can improve the control methods or the purging procedure and optimize the hydrogen consumption, resulting in more efficient hydrogen utilization and thus lower consumption of the fuel cell system.

[0017] If the tank control unit is used in a vehicle, the range is increased.

[0018] At the same time, by protecting the fuel cells of the fuel cell system from pollutants and gases, a longer service life and an energetic optimization of the entire system can be achieved.

[0019] In an advantageous development of the tank control unit, it has at least one shut-off valve through which the flow of hydrogen into and / or out of the hydrogen storage can be blocked, i.e. prevented. Accordingly, a first shut-off valve can be provided to block the flow of hydrogen into the hydrogen storage and a second shut-off valve can be provided to block the flow of hydrogen out of the hydrogen storage. In this case, the evaluation unit is designed to control the at least one shut-off valve to block the flow directly and / or via the communication interface when the proportion of pollutants in the hydrogen is exceeded. The control can also take place via intermediate points, such as control units, using the reporting signal.

[0020] Furthermore, an equally advantageous variant of the tank control unit provides that it has at least one purge valve, which can also be referred to as a drain valve. Through this, a pollutant collected or present in the hydrogen storage tank can be drained from the hydrogen storage tank. In this case, the evaluation unit is designed to control the at least one purge valve, directly and / or via the communication interface, to drain the pollutant(s) from the hydrogen storage tank when the proportion of pollutants in the hydrogen is exceeded. As with the shut-off valve, the control can be via intermediate points, such as additional control units, and by means of the signal. Preferably, one purge valve is provided for each tank of the hydrogen storage tank, whereby one purge valve can be used to purge one tank at a time, so that the tanks can also be purged independently of one another or separately.can be rinsed individually.

[0021] According to the invention, the communication interface is designed to communicate with the tank system during a refueling or refueling process in which a tank system is at least temporarily fluidly connected to the hydrogen storage device, so that hydrogen can flow from the tank system into the hydrogen storage device. By means of the communication, which can optionally be carried out via the reporting signal, the tank system can also be controlled directly by the tank control unit.

[0022] It is further provided that the communication interface is designed to communicate wirelessly, in particular via infrared, with the tank system. A transmitter and / or a receiver is integrated directly into a tank nozzle for connecting the hydrogen storage unit to the tank system.

[0023] As previously mentioned, the tank control unit can also perform further monitoring functions on or in the hydrogen storage device. For this purpose, according to an advantageous embodiment, the tank control unit has at least one pressure measuring device for detecting a pressure of the hydrogen stored in the hydrogen storage device and / or flowing into and / or out of the hydrogen storage device. Additionally or alternatively, the tank control unit can have at least one temperature measuring device for detecting a temperature of the hydrogen stored in the hydrogen storage device and / or flowing into and / or out of the hydrogen storage device.

[0024] In particular, the tank control unit can provide a high-pressure sensor as the first pressure measuring device in a high-pressure region of the hydrogen storage device, a low-pressure sensor as the second pressure measuring device in a low-pressure region of the hydrogen storage device, and a tank pressure sensor as the third pressure measuring device, each for a tank of the hydrogen storage device. The high-pressure sensor and the low-pressure sensor are integrated, in particular, into a pressure reduction device, in which the hydrogen stored in the hydrogen storage device, or more precisely in the tank under high pressure, is reduced from high pressure to low pressure before it flows out of the hydrogen storage device.

[0025] A further aspect of the invention relates to a hydrogen storage system comprising a hydrogen storage device and a tank control unit according to the invention. The hydrogen storage device can comprise one or more tanks for storing the hydrogen.

[0026] In addition to the tank control unit and the hydrogen storage system, one aspect of the invention also relates to a method for controlling a tank control unit according to the invention. According to this method, the evaluation unit continuously or intermittently compares the proportion of pollutants or their concentration in the hydrogen with the predetermined limit value and, if the proportion or concentration of pollutants in the hydrogen is exceeded, sends the warning signal via the communication interface.

[0027] A further development of the method is also advantageous in which the evaluation unit, when the proportion of pollutants in the hydrogen and in particular in the hydrogen flowing into the hydrogen storage tank or flowing out of the hydrogen storage tank is exceeded, activates the at least one shut-off valve, as explained above, and blocks the flow of hydrogen into the hydrogen storage tank and / or out of the hydrogen storage tank.

[0028] Furthermore, a variant of the method is advantageous in which the evaluation unit, when the proportion of pollutants in the hydrogen and in particular in the hydrogen flowing into the hydrogen storage or flowing out of the hydrogen storage is exceeded, activates at least one purge valve, as previously explained, and releases the pollutant(s) from the hydrogen storage.

[0029] In addition, a variant can also be provided in which the evaluation unit controls an associated valve when the proportion of pollutants in the hydrogen and in particular in the hydrogen flowing in the hydrogen system of a fuel cell is exceeded, so that the pollutant or pollutants can be discharged from the hydrogen system of the fuel cell.

[0030] The features disclosed above can be combined as desired, as long as this is technically possible and they do not contradict each other.

[0031] Other advantageous developments of the invention are characterized in the subclaims or are presented in more detail below, together with the description of the preferred embodiment of the invention, with reference to the figures. They show: Fig. 1: a tank control unit; Fig. 2: initialization sequence of the tank control unit; Fig. 3: normal operation sequence of the tank control unit.

[0032] The figures are exemplary schematic.

[0033] In Figure 1 An exemplary structure of a tank control unit is shown. The central core of the tank control unit is the evaluation unit 100, which has a control unit 101 and an optional temperature sensor 102 for detecting the temperature of the control unit 101 and / or an environment adjacent to the control unit 101. The communication interface, via which the evaluation unit 100 can communicate with systems 110 and subassemblies 120, 130 of the tank control unit that do not belong to the tank control unit, is also integrated into the control unit 101.

[0034] In particular, data from the subassemblies 120, 130, such as measured values ​​from measuring devices, are evaluated in the evaluation unit 100 and more precisely in the control unit 101 and forwarded to systems 110 not belonging to the tank control unit according to a method implemented in the control unit 101 or actuators, in particular valves, integrated into the subassemblies 120, 130 of the tank control unit are controlled.

[0035] In the present case, the tank control unit communicates with a tank system 111 via the communication interface integrated into the control unit 101, at least during a refueling process. Furthermore, the tank control unit communicates with a fuel cell management system 112, which controls the fuel cells of a fuel cell system, as well as with other vehicle control units or, in general, with a vehicle bus system 113.

[0036] A first subassembly 120 of the tank control unit is integrated into a device for reducing the pressure of the high-pressure hydrogen in the hydrogen storage tank. Subassembly 120 provides a high-pressure sensor 123 as a measuring device for detecting the pressure of the hydrogen in a high-pressure region of the device and a low-pressure sensor 124 as a measuring device for detecting the pressure of the hydrogen in a low-pressure region of the device. These sensors are each connected to the evaluation unit 100 via signaling and transmit the respectively detected values ​​to the evaluation unit 100.Furthermore, the first subassembly 120 contains a high-pressure valve 121 for blocking and / or controlling the flow of hydrogen into the high-pressure region of the device and a low-pressure valve 122 for blocking and / or controlling the flow of hydrogen out of the low-pressure region of the device, which are each also signal-connected to the evaluation unit 100 and can be controlled by it, so that in the event of a fault or if an excessively high concentration of pollutants is measured in the device or the hydrogen storage device, the flow of hydrogen into and / or out of the device can be blocked to reduce the pressure.

[0037] The second subassembly 130 monitors the hydrogen storage or a tank of the hydrogen storage. For this purpose, the second subassembly 130 includes a temperature sensor 131 as a temperature measuring device, a pressure sensor 132 as a pressure measuring device, a volume or fill level sensor 133 for detecting the hydrogen fill level of the tank, a first shut-off valve 134 acting as a safety valve for the tank, and a second shut-off valve 135 acting as a tank valve for blocking the flow of hydrogen into the tank during the refueling process. Furthermore, a purge valve 136 is provided, through which the tank can be purged.

[0038] Figure 2 specifies the process of starting or initializing the Figure 1 shown tank control unit and includes the following steps or transition conditions as a simplified flow chart: 201Start of the process or initialization 202Functional test of all measuring devices and valves connected to the evaluation unit 100 203Are all measuring devices and valves connected to the evaluation unit 100 functional? 203a If yes, then continue to 205 203b If no, then continue to 204 204Output of a corresponding error message to a higher-level system, such as the fuel cell management system 112 205Detection of the fill level of the hydrogen storage tank with the fill level sensor 133 206Is the fill level above a minimum fill level of, for example, 10%? 206a If yes, then continue to 208 206b If no, then continue to 207 207Output of a corresponding error message to a higher-level system, such as the fuel cell management system 112 208Execution or start of normal operation according to Figure 3 209End of initialization of the tank control unit

[0039] Figure 3gives the sequence of normal operation of the Figure 1 shown tank control unit, which is based on the Figure 2 The initialization shown can be followed. Normal operation, or the associated process, comprises the following steps or transition conditions as a simplified flowchart: 301Start of normal operation 302Waiting for a request for hydrogen from a fuel cell of the fuel cell system, wherein the request can be transmitted in particular by the fuel cell management system 112 to the evaluation unit 100 303Opening of the high-pressure valve 121 304Relieving the hydrogen flowing into the pressure reduction device and under high pressure to a low pressure that can be designated as the system pressure 305Opening of the low-pressure valve 122 306Providing the hydrogen flowing from the pressure reduction device to the fuel cell 307Detecting the parameters of the hydrogen flowing from the tank of the hydrogen storage device into the pressure reduction device by means of at least the temperature measuring device 131 and the pressure measuring device 132 308Detecting the pollutants in the hydrogen flowing from the tank of the hydrogen storage device into the pressure reduction device by means of at least oneMeasuring device for detecting predetermined components of the hydrogen 309 Operation of the fuel cell using the hydrogen flowing from the tank via the pressure reduction device 310 Detection of the parameters of the hydrogen flowing in the hydrogen system of the fuel cell system having the fuel cell, for example, using further pressure and temperature measuring devices, and preferably detection of the pollutants in the hydrogen flowing through the hydrogen system using at least one further measuring device for detecting predetermined components of the hydrogen 311 Does the concentration of the pollutants exceed a predetermined limit? 311a If yes, then continue to 312 311b If no, then continue to 313 312 "Purging" the tank of the hydrogen storage device and / or the hydrogen system of the fuel cell system using the purge valve 136 313 Storing or storing the hydrogen consumed by the fuel cell 314 Waiting foran end of the hydrogen request 315Closing of the high-pressure valve 121 and the low-pressure valve 122 316End of the process or normal operation

Claims

1. A tank control unit of a hydrogen reservoir for a fuel cell system, wherein the tank control unit comprises a tank nozzle and an evaluation unit (100) and at least one measuring device for detecting predetermined components of hydrogen stored in the hydrogen reservoir and / or flowing into the hydrogen reservoir and / or flowing out of the hydrogen reservoir, wherein the evaluation unit (100) has a communications interface and is designed to determine a proportion of pollutants in the hydrogen from the components of the hydrogen detected by at least one measuring device, to compare the proportion of pollutants with a predetermined limit value, and to send a notification signal via the communications interface if the proportion of pollutants in the hydrogen is exceeded, wherein the communications interface is designed to communicate with the tank system (111) during a refueling process in which a tank system (111) is fluidically connected to the hydrogen reservoir, so that hydrogen can flow from the tank system (111) into the hydrogen reservoir, wherein the communications interface is designed to communicate wirelessly and in particular via infrared with the tank system (111), characterized in that a transmitter and / or a receiver of the communications interface is integrated directly into the tank nozzle.

2. The tank control unit according to claim 1 comprising at least one shut-off valve (134, 135) through which a flow of the hydrogen into and / or out of the hydrogen reservoir can be blocked, wherein the evaluation unit (100) is designed to control at least one shut-off valve (134, 135) in order to block the flow directly and / or via the communications interface when the proportion of pollutants in the hydrogen is exceeded.

3. The tank control unit according to claim 1 or 2 comprising at least one purge valve (136) through which a pollutant collected in the hydrogen reservoir can be discharged from the hydrogen reservoir, wherein the evaluation unit (100) is designed to control at least one purge valve (136) in order to release the pollutant from the hydrogen reservoir directly and / or via the communications interface when the proportion of pollutants in the hydrogen is exceeded.

4. The tank control unit according to any one of the preceding claims comprising at least one pressure measuring device (123, 124, 132) for detecting a pressure of the hydrogen stored in the hydrogen reservoir and / or flowing into the hydrogen reservoir and / or flowing out of the hydrogen reservoir and / or comprising at least one temperature measuring device (131) for detecting a temperature of the hydrogen stored in the hydrogen reservoir and / or flowing into the hydrogen reservoir and / or flowing out of the hydrogen reservoir.

5. A hydrogen reservoir system with a hydrogen reservoir and a tank control unit according to any one of the preceding claims.

6. A method for controlling a tank control unit according to any one of preceding claims 1 to 4, wherein the evaluation unit (100), continuously or at intervals, compares the proportion of pollutants with the predetermined limit value and, if the proportion of pollutants in the hydrogen is exceeded, sends the notification signal via the communications interface.

7. The method according to the preceding claim, wherein, if the proportion of pollutants in hydrogen is exceeded, the evaluation unit (100) activates at least one shut-off valve (134, 135) according to claim 2 and blocks the flow of hydrogen into the hydrogen reservoir and / or out of the hydrogen reservoir.

8. The method according to preceding claim 6 or 7, wherein, if the proportion of pollutants in the hydrogen is exceeded, the evaluation unit (100) activates the at least one purge valve (136) according to claim 3 and releases the pollutant from the hydrogen reservoir.