Pressure vessel system for a vehicle

Abstract

A pressure vessel system for a vehicle includes a pressure vessel and a fuel line. The system also includes a blocking unit which, in an inoperative state, prevents fuel from passing out of the pressure vessel into the fuel line. A control unit for the blocking unit is designed, under the action of electrical energy, to transfer the blocking unit from the inoperative state into an active state in which fuel can pass out of the pressure vessel into the fuel line. Furthermore, the system includes an electrically conducting connection to an electrical system of the vehicle via which electrical energy can be provided for controlling the blocking unit. In addition, the system includes an access interface unit via which electrical energy for controlling the blocking unit can be provided from an external energy supply if no electrical energy is available from the electrical system of the vehicle.

Claims

1. A pressure vessel system for a vehicle, comprising: a pressure vessel configured to receive fuel; a fuel line configured to transfer fuel from the pressure vessel to a fuel consumer; a blocking unit configured to transition between a deenergized state, in which the blocking unit is closed and thereby prevents an outflow of fuel from the pressure vessel into the fuel line, and an energized state, in which the blocking unit is open and thereby does not prevent the outflow of fuel; a control unit configured to control electrical energy to the blocking unit so as to transition the blocking unit between the deenergized state and the energized state, wherein the control unit is configured to receive the electrical energy from an onboard electrical network of the vehicle; and an access interface unit configured to electrically connect the control unit to an external power supply so as to provide the electrical energy in lieu of and independent from the onboard electrical network.

2. The pressure vessel system according to claim 1, wherein the access interface unit forms a plug-in connection with an external interface unit.

3. The pressure vessel system according to claim 2, wherein the access interface unit includes encoding.

4. The pressure vessel system according to claim 1, further comprising a junction and/or a switch configured to electrically connect the control unit to each of: the onboard electrical network of the vehicle, and the access interface unit.

5. The pressure vessel system according to claim 1 further comprising an internal interface unit through which the electrically conductive connection is connectable to the onboard electrical network of the vehicle.

6. The pressure vessel system according to claim 1 further comprising: a switching element which connects the access interface unit electrically conductively to the control unit or separates the access interface unit from the control unit; wherein the switching element separates the access interface unit from the control unit in a standard operating state; wherein the switching element connects the access interface unit electrically conductively to the control unit in response to a trigger signal.

7. The pressure vessel system according to claim 6, wherein the trigger signal is an accident signal.

8. The pressure vessel system according to claim 1 further comprising: a relief valve that carries fuel from the fuel line into an environment of the pressure vessel system; and a coupling element to which an external discharge channel is connectable for discharge of fuel from the fuel line; wherein the relief valve is disposed between the fuel line and the coupling element; and wherein the coupling element opens the relief valve when an external discharge channel has been connected to the coupling element.

9. The pressure vessel system according to claim 8 further comprising: a pressure converter, wherein a pressure of fuel in the fuel line between the pressure vessel and the fuel consumer is reducible by the pressure converter; wherein the relief valve and the coupling element are disposed on a first section of the fuel line between the pressure converter and the fuel consumer; or wherein the relief valve and the coupling element are disposed on a second section of the fuel line between the pressure vessel and the pressure converter.

10. A discharge unit in combination with the pressure vessel system according to claim 1, the discharge unit comprising: an external interface unit that is connected to the access interface unit of the pressure vessel system; and an external power supply, wherein the external power supply supplies the electrical energy via the external interface unit.

11. The discharge unit in combination with the pressure vessel system according to claim 10, the discharge unit further comprising a control unit configured to generate a control signal and to provide the control signal to the external interface unit in order to cause the control unit of the pressure vessel system to transfer the blocking unit into the active state.

12. The discharge unit in combination with the pressure vessel system according to claim 11, wherein the control unit of the discharge unit is configured to modulate a current for the control unit of the pressure vessel system to generate the control signal.

13. The discharge unit in combination with the pressure vessel system according to claim 12, wherein the control unit of the discharge unit is configured to modulate the current for the control unit of the pressure vessel system by pulse width modulation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1 and 2 show an example of a pressure vessel system for a vehicle; and

(2) FIG. 3 shows a flow diagram of an example of a method for transferring a pressure vessel into a safe state.

DETAILED DESCRIPTION OF THE DRAWINGS

(3) As explained at the beginning, this document deals with a pressure vessel system (in particular a compressed hydrogen storage system (=CHS system)) for a motor vehicle. The pressure vessel system is used to store gaseous fuel under ambient conditions. The pressure vessel system can be used, for example, in a motor vehicle powered by compressed natural gas (CNG) or liquefied natural gas (LNG) or hydrogen.

(4) Such a pressure vessel system includes at least one pressure vessel or pressure tank. The pressure vessel can be, for example, a cryogenic pressure vessel (=CcH2) or a high-pressure gas vessel (=CGH2).

(5) High-pressure gas vessels are embodied to store fuel, essentially at ambient temperatures, permanently at a nominal operating pressure (also called the nominal working pressure or NWP) of approx. 350 bar gauge (=overpressure compared to the atmospheric pressure), further preferably of about 700 bar gauge or more. A cryogenic pressure vessel is capable of storing the fuel at the above-mentioned operating pressures even at temperatures well below the operating temperature of the motor vehicle.

(6) FIG. 1 shows an example of a pressure vessel system 100 with a pressure tank or pressure vessel 110, which can be used to provide fuel (in particular hydrogen) for a fuel consumer (for example a fuel cell) 101 of a vehicle 10. The pressure vessel 110 is connected to the fuel consumer 101 via a fuel line 112, 117.

(7) The pressure vessel 110 may comprise end pieces 111 on the end faces, which can be used for holding the pressure vessel 110 during the manufacture of the pressure vessel 110. Furthermore, an opening can be provided on an end piece 111 through which fuel from the pressure vessel 110 can be fed out (for example via a valve 115 to the line 112). A pressure relief device (not shown) may also be arranged at an opening of the pressure vessel 110 that can trigger in the presence of a certain trigger condition (for example in the presence of a certain temperature) to discharge fuel from the pressure vessel 110 into the environment of the pressure vessel 110, thus reducing the pressure in the pressure vessel 110.

(8) The one or more valves 115 (commonly referred to as blocking units) of a pressure vessel 110 are typically closed in a rest state, so that no fuel can pass out from the pressure vessel 110 via one or more valves 115. A valve 115 of a pressure vessel 110 can be connected via one or more electrical lines 105 to a control unit 102, wherein the control unit 102 is set up to connect the valve 115 to a current and/or voltage source 106 (for example to a 12V onboard network of a vehicle) to transfer the valve 115 from the closed rest state to an open active state. The valve 115 can remain in the open active state as long as the valve 115 is coupled to the current and/or voltage source. On the other hand, the valve 115 can automatically return to rest as soon as the valve 115 is decoupled from the current and/or voltage source. The control unit 102 can be coupled to the valve 115 via an (internal) plug-in connection 103, 104 with interface units 103, 104 (for example with a plug and a socket).

(9) The pressure vessel 110 can be refueled with fuel via a refueling access 114 (for example via a tank nipple). In particular, fuel from a tank column can be conveyed via the fuel line 112 into the pressure tank 110 via the refueling access 114. In this case there is typically a non-return valve 201 (see FIG. 2) between the refueling access 114 and the fuel line 112, which prevents a return of fuel from the pressure tank 110 to the refueling access 114.

(10) A fuel cell 101 is typically operated with a relatively low pressure (for example in the region of 10-20 bar), wherein the low pressure for the fuel cell 101 is usually substantially less than the high pressure (for example in the region of 700 bar) in the fuel line 112 and in the pressure tank 110. Between the pressure tank 110 and the fuel cell 101, therefore, a pressure converter 116 (in particular a pressure regulator) may be arranged, which is set up to transfer fuel from the high-pressure fuel line 112 (which has a relatively high pressure) into a low-pressure fuel line 117 (with a relatively low pressure). The fuel is then fed to the fuel cell 101 via the low-pressure fuel line 117.

(11) FIG. 2 shows a pressure vessel system 100 for a vehicle with a plurality of pressure vessels 110. Furthermore, FIG. 2 shows control units 215 for the pressure vessel valves 115 of the individual pressure vessels 110. The control units 215 can each include an electromagnet, by means of which a magnetic field for opening a valve 115 can be generated when deenergizing.

(12) A pressure vessel 110 of a pressure vessel system 100 of a vehicle is thus typically connected via one or more valves 115 (in particular via one or more over-temperature valves (OTVs)) to a pressure converter 116. To get fuel from a pressure vessel 110, one or more tank valves 115 must be powered by the vehicle's onboard network and thus opened. A tank valve 115 can typically not be emptied without an onboard power supply (for example after an accident or after a technical defect), as the electrically operated tank shut-off valve 115 cannot be controlled. Thus, in such a situation, emptying or pressure relief of the pressure vessel 110 is not possible.

(13) The one or more valves 115 of a pressure vessel 110 can be electrically conductively coupled via the electrically conductive signal line 105 to an access interface unit 122. The access interface unit 122 can be disposed in a place in a vehicle that is easily accessible to a user (for example for a helper after an accident). The access interface unit 122 can be set up according to the internal interface unit 104 to the control unit 102.

(14) The access interface unit 122 can enable a user to connect a vehicle-external energy supply 134 via a vehicle-external interface unit 132 to the access interface unit 122 and thus to the control unit 215 of a valve 115. The vehicle-external external energy supply 134 can be designed (for example in combination with an external control unit 202) to control the control unit 215 of a valve 115 in order to cause the valve 115 to change from the closed resting state into the opened active state (for example analogous to the valve control unit 102, for example). Thus, even in the event of interruption of the energy supply from an onboard network of a vehicle, a pressure reduction in a pressure vessel 110 can be reliably implemented.

(15) Thus, a device for independent activation of the defueling of a pressure vessel 110 (in particular a CGH2 and/or CCH2 pressure vessel) in a vehicle is described. For this purpose, the one or more control lines 105 between the valve control unit 102 of the vehicle and the one or more blocking units (in particular valves) 115 of the pressure vessel 110 can be led to one or more safely accessible locations of the vehicle (for example next to a high-voltage rescue isolation unit in the interior of the vehicle). External access to the one or more control lines 105 can then be provided via a disconnectable plug-in connection or via a switch with an access plug (i.e., via an access interface unit 122).

(16) The access interface unit 122 can comprise specific encoding 107 (for example corresponding to an internal vehicle interface unit 104 to the valve control unit 102). The encoding 107 can be implemented, for example, by one or more (non-conductive) grooves and/or cones. The encoding 107 ensures a correct connection between the access interface unit 122 and a vehicle-external interface unit 132. Furthermore, the use of impermissible vehicle-external interface units 132 can be avoided.

(17) A vehicle-external, independent device 132, 134 (also referred to in this document as a discharge unit) can be provided, by means of which a power supply corresponding to the onboard power supply (for example a 12V battery) can be provided for external energization of the one or more electrically operated blocking units 115. The vehicle-external device 132, 134 comprises a vehicle-external interface unit 132 (for example a connection plug that may be encoded), which is designed to form a plug-in connection with the access interface unit 122. In addition, the vehicle-external device 132, 134 includes an energy supply 134 and a control unit or modulation unit 202, which produces a control signal corresponding to the onboard control unit 102 (for example a PWM signal) for activating one or more electrical blocking units 115.

(18) The one or more valves 115 of a pressure vessel 110 can thus be energized externally. For this purpose, an external current and/or voltage source can be applied via an access interface unit (for example a plug socket) 122. The connection of one or more valves 115 in this current path between the access interface unit 122 and the one or more valves 115 can be protected against misuse by one or more safety or switching elements 108, such as a contact triggered by a crash signal.

(19) By opening the one or more blocking units 115 of the one or more pressure vessels 110, fuel from the one or more pressure vessels 110 can enter the fuel line 112, 117. The pressure vessel system 100 may comprise a relief valve 231 through which fuel can be discharged from the fuel line 112 into an environment of the pressure vessel system 100, in particular into an environment of the vehicle. In particular, a vehicle-external discharge hose 133 can be connected to the relief valve 231 by means of a coupling 131, 121. By coupling the discharge hose 133, the relief valve 231 can be opened, so that fuel can be discharged from the pressure vessel system 100.

(20) The coupling element 121 of the pressure vessel system 100 (for example a connection of a discharge channel 133) can be arranged in a place of a vehicle that is easily accessible to a user, for example for rescue workers. For example, a discharge interface 230 can be provided on a vehicle on which both the coupling element 121 and the access interface unit 122 are arranged. If necessary, the coupling element 121 and/or the access interface unit 122 can be arranged in immediate proximity to the refueling access.

(21) The relief valve 231 and/or the coupling element 121 can preferably be coupled to the low-pressure fuel line 117 (as shown in FIGS. 1 and 2). In this way, fuel can be discharged in a controlled manner. Alternatively, the relief valve 231 and/or the coupling element 121 can be coupled to the high-pressure fuel line 112, which allows an accelerated discharge of fuel.

(22) A discharge tube or hose 133 (generally a discharge channel) can thus be connected to a central quick-action coupling 121, 131 to discharge fuel from the pressure vessel system 100. The triggering of the relief valve 231 can be carried out by the coupling 121, 131, which opens the relief valve 231 mechanically as a result of the plug-in or which comprises a hydraulic or electrical actuation mechanism for opening the relief valve 231.

(23) Thus, a central discharge device is described, which enables, for example, emergency emptying of a pressure vessel system 100 by rescue workers. By providing an access interface unit 122, a fast, simple and standardizable or standardized emergency discharge of a pressure vessel 110 can be provided as required, without having to rely on the power supply and bus systems of a vehicle. Thus, a pressure vessel 110 (for example after an accident) can be reliably and efficiently transferred to a safe state. Advantageously, standardization of the plug-in device and the control signal for controlling a blocking unit 115 of a pressure vessel 110 can be carried out in order to provide a universal vehicle-external discharge unit 132, 134 for rescue workers and workshops for pressure relief of a pressure vessel 110.

(24) FIG. 2 shows a flow diagram of an example of a method 300 for the relief of a pressure vessel system 100. The method 300 includes coupling 301 the access interface unit 122 of the pressure vessel system 100 to an external energy supply 134. Thus, the one or more blocking units 115 of the one or more pressure vessels 110 of the pressure vessel system 100 can be supplied with electrical energy (even in the case of interruption of the energy supply from the electric power supply of a vehicle) in order to open the one or more blocking units 115 and thereby to release fuel from the one or more pressure vessels 110 into the fuel line 112, 117 of the pressure vessel system 100.

(25) In addition, the method 300 includes opening 302 a relief valve 231 of the fuel line 112, 117 to transfer fuel from the fuel line 112, 117 to an environment of the pressure vessel system 100. The relief valve 231 can be opened, for example, by connecting a discharge channel 133 (for example a hose) via a coupling element 121 to the pressure vessel system 100, in particular to the fuel line 112, 117.

(26) Thus, a device or a system for independent activation of the defueling of a gas pressure vessel 110 (for example CGH2+CCH2) in a vehicle is described (for example if the onboard network of the vehicle is not functioning). In this case, the one or more electrical lines 105 to a blocking unit 115 of the pressure vessel 110 are moved to a safely accessible connection point (i.e., to an access interface unit 122). The connection point can be arranged, for example, next to an HV (high-voltage) rescue isolation point in the interior of the vehicle.

(27) With an external independent discharge unit, a power supply corresponding to the onboard power supply (for example a 12V battery) can be implemented for external energization of the electrically operated blocking unit 115 of the pressure vessel 110. The external power supply 134 can be coupled via a connection plug 132 to the access interface unit 122, wherein the connection plug 132 is encoded according to the access interface unit 122. By means of a control or modulation unit 202, a control signal for activating the blocking unit 115 can be generated according to the onboard control unit 102 (for example by PWM modulation). The fuel can then be fed out of the pressure vessel system 100 via a service port/defueling port 121 of the vehicle.

(28) The present invention is not limited to the exemplary embodiments shown. In particular, it should be noted that the description and the Figures are intended to illustrate only the principle of the proposed methods, devices and systems.

LIST OF REFERENCE CHARACTERS

(29) 100 Pressure vessel system 101 Fuel consumer 102 Control unit 103, 104 Interface unit 105 Control line 110 Pressure vessel 111 End piece 112, 117 Fuel line 114 Refueling access 115 Blocking unit (valve) 116 Pressure converter 121, 131 Coupling element 122 Access interface unit 132 System-external interface unit 133 Discharge channel 134 System-external energy supply 201 Non-return valve 202 System-external control unit 215 Control unit 230 Discharge interface 231 Relief valve 300 Method for discharging a pressure vessel system 301, 302 Steps of the method

(30) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.