Method for determining tank filling amount of tank arrangement and tank arrangement for storing gaseous fuel

Abstract

The invention relates to a method for determining a tank filling amount of a tank arrangement having a plurality of tank containers (TB), each tank container being connected to a gas line system (GL) by means of a respective valve device which can be switched between an open state and a closed state, the method comprises the following steps of: reading the filling quantity of all the tank containers, which is obtained and stored when the vehicle is operated in advance, from the data memory; switching the valve device from a closed state to an open state such that gas can flow from the tank container into the gas line system; determining the mass of the gaseous fuel taken out of the gas line system (GL) during a predetermined time period (t) during operation; and determining the current filling amount of all the tank containers by subtracting the determined mass of the extracted gaseous fuel from the stored filling amount during a predetermined time period.

Description

Technical Field

[0001] The invention relates to a method for determining a tank filling level of a tank arrangement and a tank arrangement for storing gaseous fuel. Background Art

[0002] Safety devices and / or valves can be installed in known pressure storage tanks. For this purpose, fuel cell systems or storage tanks for gaseous media with a tank assembly are known. Pressure storage tanks can be equipped with valves to close or discharge the tank contents.

[0003] In a common hydrogen tank system with multiple gas tanks, each of which is equipped with its own tank valve, not all tanks necessarily have their own pressure sensors. After pressure equilibrium is achieved, it is ideal to determine the filling level of a tank and multiple tanks.

[0004] DE 11 2006 003 013 B4 describes a tank with a fitting and a valve, wherein the valve is fastened in the fitting. Summary of the Invention

[0005] The present invention provides a method for determining a tank filling level of a tank arrangement according to claim 1 and a tank arrangement for storing gaseous fuel according to claim 4 .

[0006] Preferred embodiments are the subject matter of the dependent claims.

[0007] The present invention is based on the idea of ​​providing a method for ascertaining a tank fill level of a tank arrangement and a tank arrangement for storing gaseous fuel, wherein the storage state (SOC) of the tank arrangement can be better ascertained.

[0008] Advantageously, it is possible to avoid and / or reduce inaccuracies when determining the tank fill level of one or more tank containers (e.g., a fuel cell of a vehicle) during operation and after starting the vehicle, which inaccuracies arise for different tank pressures, for example due to different tank heating / cooling conditions when the vehicle is stationary.

[0009] According to the present invention, in a method for ascertaining the tank filling level of a tank arrangement having a plurality of tank containers, each tank container is connected to a gas line system by means of a corresponding valve device, which is switchable between an open state and a closed state. The method comprises the following steps: reading the filling levels of all tank containers ascertained and stored during a previous operation of the vehicle from a data memory; switching the valve devices from the closed state to the open state so that gas can flow from the tank containers into the gas line system; ascertaining the mass of gaseous fuel removed from the gas line system during a predetermined time period during operation; and ascertaining the current filling levels of all tank containers during the predetermined time period by subtracting the ascertained mass of gaseous fuel removed from the stored filling levels.

[0010] During a standstill of a vehicle having a hydrogen storage system, different pressures may develop in the individual tank containers, which may be due to different temperature changes in the individual tank containers, for example due to different heating or cooling conditions caused by different tank designs or different ambient boundary conditions.

[0011] The aforementioned computational determination of the tank filling quantity can advantageously be carried out during a predetermined period of time after the start of operation, until complete pressure equalization between the tank containers has been achieved.

[0012] According to a preferred embodiment of the method, the predetermined time period starts counting after all or at least one valve device is opened.

[0013] The predetermined time period may correspond to the time from vehicle (and fuel cell) startup to the determined or estimated pressure equalization of the tank container.

[0014] According to a preferred embodiment of the method, valve devices of a plurality of tank containers are opened when the vehicle is started, wherein the cumulative gas consumption removed within a predetermined time period is determined by integrating the consumer mass flow over time since the valve devices were opened.

[0015] The net consumption of the consumer system, in other words the gaseous fuel mass withdrawn (eg by a fuel cell as consumer) can be the cumulative gas consumption of the consumer system.

[0016] According to the present invention, a tank device for storing gaseous fuel includes a plurality of tank containers into which gaseous fuel can be filled; a gas pipeline system; at least one valve device for each tank container, which connects the corresponding tank container to the gas pipeline system, wherein the at least one valve device can be switched between an open state and a closed state, in which, in the open state, it connects the tank container to the gas pipeline system in a fluid-conducting manner, and in the closed state, it isolates the corresponding tank container in the direction of the gas pipeline system; a sensor device, which is configured to detect the temperature in each tank and the gas pressure in the gas pipeline system; and a control device, which is connected to the sensor device and is configured to perform the method according to the present invention.

[0017] One or more tank containers together with the gas piping system may constitute a gas storage system.

[0018] According to a preferred embodiment of the tank device, the control device is configured to start counting the predetermined time only after the valve device on the tank container is opened.

[0019] According to a preferred embodiment of the storage tank device, the storage tank device includes a plurality of storage tank containers, and the storage tank containers are connected to the gas pipeline and the sensor device.

[0020] According to a preferred embodiment of the tank arrangement, the control device is configured to open the valve device of the tank container when the vehicle is started.

[0021] The gas pipeline system can be used to supply gas fuel to the tank container, and can also be used to transport gas from the tank container to the engine or fuel cell of the vehicle. The valve device may include a closable valve that can be opened and closed electrically. Pressure balance between the tanks can be achieved by opening the tank valve and releasing gas to the supply pipeline of the gas pipeline system. The predetermined time until the assumed pressure balance can be long enough so that when multiple tank containers are opened after the operation of the vehicle's drive (such as the function of the fuel cell or engine) is started, the gas pressure in the gas pipeline system and the tank container can reach equilibrium. Therefore, the high internal pressure of one tank container can release more gas fuel to the gas pipeline than the low internal pressure of another tank container until the internal pressure reaches equilibrium, and then both (or more) can release the same amount per unit time.

[0022] The vehicle may be a fuel cell vehicle. The gaseous fuel may be a gaseous gas used to operate the fuel cell, such as hydrogen or other gases. Alternatively, the gaseous fuel may be a gas used in gas-powered vehicles, such as CNG or LPG, which may also be liquefied gas.

[0023] The sensor device may comprise one or more sensors, with which a pressure drop, and / or a pressure gradient, and / or a temperature gradient, and / or a temperature in a tank container or a gas line system may be detected.

[0024] The control device can be connected to the valve devices of one or more tank containers and to the sensors and can read these sensors.

[0025] The method may also have features and advantages associated with the tank arrangement, and vice versa.

[0026] Other features and advantages of the embodiments of the present invention will be apparent from the following description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The invention will now be described in more detail with reference to embodiments shown in the schematic drawings of the accompanying drawings.

[0028] It shows:

[0029] Figure 1 A schematic diagram of a tank arrangement for storing gaseous fuel according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In the figures, the same reference signs indicate identical or functionally identical elements.

[0031] according to Figure 1 A tank arrangement 1 for storing gaseous fuel for vehicles includes a plurality of tank containers TB1, TB2, TB3, TB4, TB5, and TB6, for example, gas cylinders filled or refillable with hydrogen. The tank arrangement 1 includes a valve device 2, for example, one valve device for each tank container, which is connected to or disposed on the tank container. The valve device 2 is configured to allow gaseous fuel to enter and / or exit the tank container and / or to isolate its contents. The tank arrangement 1 also includes a gas line GL in a gas line system, which is connected to at least one valve device 2; a control device SE and a sensor device Si, by means of which the method according to the present invention can be performed. The sensor device is connected to or disposed in the gas line GL and at least one tank container and is configured to determine the gas pressure in the gas line GL and the gas temperature in the at least one tank container.

[0032] A temperature sensor Si may be provided on each of the tank containers TB1 to TB6 , which may be connected to and read out by the control device SE. The tank temperature of the corresponding tank container may be determined via the corresponding temperature sensor.

[0033] Here, the sensor system Si can also include multiple sensors, such as a first sensor Si1, which can be connected to the supply lines of the first three tank containers (for example, three, although this arrangement can also vary), and a second sensor Si2, which can be connected to the remaining supply lines and the gas line GL and is configured to determine the gas pressure in the gas line GL at predetermined times. The method according to the present invention for determining pressure, pressure gradient, or other parameters can be performed on one, two, or more sensors. The control device SE can be configured to start counting the predetermined time only after the vehicle is started and / or to open the valve device 2 of the tank container (TB1, TB2, TB3, etc.) after the vehicle is started.

[0034] Although the present invention has been entirely described above with reference to preferred embodiments, the invention is not limited to the embodiments described but can be modified in many ways.

Claims

1. A method for determining the tank fill level of a tank system having a plurality of tank containers (TB), wherein: Each tank container is connected to the gas line system (GL) by means of a corresponding valve device, said valve device being switchable between an open state and a closed state, said method comprising: Reading from the data memory the fill levels of all tank containers determined and stored during a previous operation of the vehicle; switching the valve device from the closed state to the open state to allow gas to flow from the tank container into the gas piping system; determining a mass of gaseous fuel removed from the gas line system (GL) during a predetermined time period (t) during operation; and During the predetermined time period, the current fill levels of all tank containers are ascertained by subtracting the ascertained removed gaseous fuel mass from the stored fill levels.

2. The method according to claim 1, wherein The predetermined time period starts to count after all or at least one of the valve devices is opened.

3. The method according to claim 1 or 2, wherein When the vehicle is started, the valve devices of a plurality of tank containers are opened, wherein the cumulative gas consumption removed within the predetermined time period (t) is determined by integrating the consumer mass flow over time since the valve devices were opened.

4. A tank device (1) for storing gaseous fuel, comprising: a plurality of tank containers (TB) into which the gas fuel can be filled; Gas piping systems; at least one valve device (2) per tank container, said valve device connecting the respective tank container to the gas pipeline system (GL), wherein said at least one valve device (2) is switchable between an open state, in which it connects the tank container to the gas pipeline system (GL) in a fluid-conducting manner, and a closed state, in which it isolates the respective tank container from the gas pipeline system; a sensing device (Si) configured to detect the temperature within each storage tank and the gas pressure in the gas piping system; as well as A control device (SE) is connected to the sensor system (Si) and is configured to carry out the method according to claim 1 .

5. The tank device (1) according to claim 4, wherein: The control device (SE) is configured to start counting a predetermined time after the valve device on the tank container is opened.

6. The storage tank device (1) according to claim 4 or 5, comprising a plurality of storage tank containers (TB1, TB2, TB3, ...), wherein the storage tank containers are connected to the gas pipeline (GL) and the sensor device (Si).

7. The tank device (1) according to any one of claims 4 to 6, wherein: The control device (SE) is configured to open the valve device (2) of the tank container (TB1, TB2, TB3, . . . ) when the vehicle is started.

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