Distribution device and supply system

Abstract

The invention relates to a distribution device (100) for a supply system (10) for supplying a consumer with gaseous fuel, wherein a fluidic connection between a refueling connection (110) and an extraction connection (120) is provided in the distribution device (100) and ensures a pressure increase at the extraction connection (120) during a refueling operation. The invention also relates to a supply system (10) comprising such a distribution device (100).

Description

[0001] Distribution facility and supply system

[0002] The invention relates to a distribution device for gaseous fuel and a supply system for supplying a consumer with gaseous fuel.

[0003] Gaseous fuels are typically used in stationary or mobile units, such as motor vehicles, to provide them with energy. Examples of gaseous fuels include hydrogen and natural gas. These fuels can be converted into kinetic or electrical energy in a gas-powered combustion engine or a fuel cell, which can then be used to power a vehicle. To efficiently store the gaseous fuel within a unit like a vehicle, distribution systems are typically used, acting as an interface between refueling, storage, and the end user.

[0004] It is desirable to provide a distribution device that is designed differently or better than known designs, in particular by reducing the stress on the components used. It is further desirable to provide a supply system that includes such a distribution device. According to the invention, this is achieved by a distribution device and a supply system as defined in the respective main claims. Advantageous embodiments are claimed, for example, in the dependent claims. The content of the claims is incorporated into the description by express reference. The invention relates to a distribution device for gaseous fuel. The distribution device has a refueling connection for connecting a refueling line. The distribution device has a withdrawal connection for connecting a pressure reducer or a consumer of the gaseous fuel.The distribution device has a pressure vessel connection for connecting one or more pressure vessels for storing gaseous fuel. The distribution device has an electrically switchable withdrawal valve that connects the pressure vessel connection to the withdrawal port. The distribution device has a check valve that connects the refueling port to the pressure vessel connection, with the flow direction directed towards the pressure vessel connection. The distribution device has a fluidic connection that links a point between the withdrawal valve and the withdrawal port to a point between the refueling port and the check valve, for directing gaseous fuel from the refueling port to the withdrawal port.

[0005] Using such a distribution device, the pressure at the outlet port can be adjusted during refueling to match the pressure present in the pressure vessels after refueling. This prevents a significantly lower pressure from occurring immediately after refueling when the outlet valve is first opened, which would otherwise cause a sudden pressure spike. Such a pressure increase can negatively impact the long-term durability of downstream components such as pressure reducers. The distribution device described here equalizes the pressure during the refueling process via the aforementioned fluidic connection, ensuring a gradual pressure increase and preventing a significant pressure rise when the outlet valve is first opened after refueling.This can improve the service life of the distribution system and downstream components.

[0006] A distribution device is understood to be a component in a gaseous fuel supply system that serves as an interface between the refueling port, the extraction port, and pressure vessels. Refueling typically takes place via the refueling port, meaning gaseous fuel is fed from an external source to the pressure vessels for storage. This typically results in a significant increase in the internal pressure of the pressure vessels, with corresponding pressures also present in adjacent lines. The extraction port serves to direct the gaseous fuel to a consumer, which typically converts the gaseous fuel into electrical and / or mechanical energy. For example, the consumer could be a fuel cell or a gas-powered combustion engine.Typically, a pressure reducer is installed between the outlet and the consumer. This ensures that, regardless of the pressure supplied by the pressure vessels, a defined pressure is always delivered to the consumer, or that a maximum pressure is not exceeded. The pressure vessel connection is used to connect one or more pressure vessels in which the gaseous fuel is stored. These are typically pressurized during refueling and release the gaseous fuel when it is withdrawn, causing the pressure to drop again. For the distribution system described herein, it is equivalent whether one or several pressure vessels are used.

[0007] The withdrawal valve serves primarily to allow the controlled withdrawal of gaseous fuel. When no gaseous fuel is required by the consumer, the withdrawal valve is typically closed. It opens to supply the consumer with gaseous fuel. The check valve allows a path from the refueling port to the pressure vessel port during refueling and prevents backflow. During refueling, the pressure at the refueling port typically increases because an external source of gaseous fuel is connected, which refuels at a specific pressure. To refuel the pressure vessels, this pressure is typically higher than the pressure present in the pressure vessels, causing the check valve to open and thus allowing refueling.The aforementioned fluidic connection simultaneously ensures that the increased pressure is immediately present at the dispensing port and thus also in the piping systems directly connected to it. If, for example, a pressure reducer, another valve, or another pressure-controlling component is connected downstream of the dispensing port, the pressure increase extends to this component. This prevents the pressure at this component from instantly rising when the dispensing valve is first opened after refueling. The stress on this component is thereby significantly reduced.

[0008] The connections mentioned here—namely, the refueling connection, the extraction connection, and the pressure vessel connection—can be understood as connections that are clearly identifiable as such, for example, those equipped with a flange, a thread, and / or fastening devices for pipes. However, they can also refer to positions along pipes that serve to delineate the distribution system from surrounding components. These connections can be defined along existing pipes or other components and can also be ambiguous; that is, it is not strictly necessary for a distribution system to have a precisely defined refueling connection, an precisely defined extraction connection, and / or a precisely defined pressure vessel connection. For example, a range can be provided along which such a connection can be defined.

[0009] Preferably, the distribution device further comprises an additional check valve, which is arranged in the fluidic connection and whose flow direction points towards the extraction port. This enables the previously described functionality of increasing the pressure at the extraction port during refueling, while simultaneously preventing mass flow towards the refueling nozzle due to higher pressure at the extraction port. This also increases safety, as unintentional escape at the refueling port is prevented.

[0010] The distribution device can further include a throttle, which may be arranged in the fluidic connection. The throttle can, in particular, serve to limit the mass flow. It can, for example, be designed as a constriction compared to an otherwise larger diameter surrounding line. Preferably, the valve device includes a switchable valve, which is arranged in the fluidic connection. This allows the fluidic connection to be opened and closed selectively. For example, this can be an excessive flow valve (EFV). This can, for example, be a mass flow limiting valve. It can have a release mechanism based on the principle of back pressure. This can, in particular, mean that the valve opens when there is sufficient back pressure upstream of the switchable valve, especially from the refueling port.When the back pressure falls below a predetermined threshold value, the valve closes again.

[0011] The switchable valve can be electrically switchable in addition to or as an alternative to the opening option via back pressure. This allows for targeted control of the switchable valve, for example, using vehicle electronics.

[0012] The distribution device may further include a bypass valve that connects a point between the dispensing valve and the dispensing port to a point between the pressure vessel port and the check valve. This bypass valve may be mechanically switchable. In particular, this may mean that it can be switched by a manually applied force, and especially that it is non-electrically switchable. Such a bypass valve allows pressure vessels to be emptied even if, for example, the dispensing valve should become inoperable. The bypass valve may, in particular, be connected in parallel to the dispensing valve.

[0013] In particular, the distribution device may be equipped with a pressure sensor for measuring the pressure at the outlet port. This enables pressure monitoring. The pressure sensor may, for example, be connected to control electronics such as vehicle electronics. Alternatively or additionally, a pressure sensor may also be provided for measuring the pressure at the refueling port. Especially if the switchable valve mentioned above, which may be located in the fluidic connection, is not present, the distribution device may be equipped with only one pressure sensor. This may also apply to a complete supply system as described below. This pressure sensor may be arranged, in particular, to measure the pressure at either the outlet port or the refueling port.

[0014] The invention further relates to a supply system for providing a consumer with gaseous fuel. The supply system includes a distribution device as described herein. All embodiments described herein can be used with regard to the distribution device. The supply system preferably has a refueling nozzle that is fluidically connected to the refueling port. The refueling nozzle is typically a device that can be connected to an external source of gaseous fuel, and the refueling nozzle can, for example, be designed to be connected to a hose for supplying gaseous fuel such as hydrogen or natural gas. This enables refueling.

[0015] The supply system preferably includes one or more pressure vessels connected fluidically to the pressure vessel connection. These vessels can store the gaseous fuel supplied through the refueling nozzle. Furthermore, the supply system preferably includes a pressure reducer connected to the withdrawal port. Such a pressure reducer can provide a defined pressure to a downstream consumer and / or limit the pressure for that consumer. On the side of the pressure reducer opposite the withdrawal port, it can be fluidically connected to a consumer such as a gas-powered combustion engine or a fuel cell.

[0016] In particular, it may be provided that the supply system has only one pressure sensor. Reference is made to the explanations already given above in this regard.

[0017] The supply system is, in particular, a system that contains more components than the distribution system mentioned above. The distribution system is therefore one component of the supply system. The supply system is typically designed to perform the relevant functionalities for supplying a consumer of gaseous fuel, such as a mobile unit like a motor vehicle. This includes storing gaseous fuel in pressure vessels, refueling these pressure vessels, and extracting gaseous fuel to supply the consumer.

[0018] In other words, it has been shown that in prior art designs where the refueling and extraction paths are connected via a solenoid valve, these paths are separated during refueling. Therefore, when switching from refueling to extraction (driving), the extraction unit can experience rapid and significant pressure increases. A pressure sensor is typically used for leak detection in each area. A high-pressure extraction unit, especially a pressure regulator, can thus experience a large number of rapid pressure increases over its service life, particularly after refueling or maintenance. This can lead to high stress on the component.

[0019] By integrating the fluidic connection mentioned above, for example with a throttle, the refueling path can be connected to the withdrawal path. This allows for a continuous pressure build-up in the high-pressure section of the withdrawal unit, especially during refueling. A sudden pressure increase is thus avoided. Additionally, in the event of a failure of the pressure control unit, the outgoing hydrogen mass flow can be limited.

[0020] This fluidic connection can be equipped with an additional check valve, resulting in two check valves in the refueling direction. This increases safety and ensures compliance with any applicable legal regulations. In this case, a pressure sensor in the high-pressure side of the extraction path may suffice to monitor for external leaks. If no additional check valve is integrated, a pressure sensor in either the refueling or high-pressure side of the extraction path can be used for this purpose. In this case, a second pressure sensor is not required.

[0021] The designs described herein can be used in particular for motor vehicles such as passenger cars, motorcycles, or commercial vehicles. Specifically, they can be used for storing gaseous fuels under ambient conditions. They can be used in particular in motor vehicles powered by compressed natural gas (CNG), liquefied natural gas (LNG), or hydrogen. The supply system can be fluid-connected to at least one energy converter designed to convert the chemical energy of the fuel into other forms of energy. The pressure vessels can be designed, for example, as composite overwrapped pressure vessels. A pressure vessel can be designed, in particular, as a cryogenic pressure vessel or a high-pressure gas holder.High-pressure gas cylinders are designed to store fuel continuously at ambient temperatures at a nominal working pressure (NWP) of at least 350 bar (gauge pressure above atmospheric pressure) or at least 700 bar (gauge pressure). A cryogenic pressure vessel is suitable for storing fuel at the aforementioned operating pressures even at temperatures significantly lower (for example, more than 50 K or more than 100 K) than the operating temperature of the vehicle.

[0022] A pressure reducer is typically connected to the distribution device described herein, or to its extraction port, and, conversely, to a fuel cell, in particular to its anode subsystem, or to a gas-powered internal combustion engine. A pressure reducer is typically designed to reduce the fuel inlet pressure at the inlet of the pressure reducer to a fuel outlet pressure or back pressure at the outlet of the pressure reducer. As a rule, a pressure reducer includes a pressure reducing valve that ensures that a specific outlet pressure is not exceeded, despite differing inlet pressures. The fuel expands within the pressure reducer. The invention will now be described with reference to the accompanying drawing. The drawing shows:

[0023] Fig. 1: a supply system, and Fig. 2: a distribution device.

[0024] Fig. 1 shows a supply system 10 for supplying a consumer (not shown) with gaseous fuel according to an embodiment of the invention. The supply system 10 includes a distribution device 100 according to an embodiment of the invention. The distribution device 100 is shown only schematically in Fig. 1 and is explained in more detail below with reference to Fig. 2.

[0025] The distribution device 100 has a refueling port 110, a withdrawal port 120, and a pressure vessel port 130. A refueling nozzle 15 is connected to the refueling port 110 via a refueling line 12. A hose or other equipment from a filling station can be connected to the refueling nozzle 15 to supply gaseous fuel for refueling. Several pressure vessels 30 are connected to the pressure vessel port 130 via a connecting line 35. Gaseous fuel can be stored in the pressure vessels 30, which is supplied during refueling and serves to supply a consumer (not shown).A pressure reducer 20 is connected to the extraction port 120. This pressure reducer is fluidically arranged between the extraction port 120 and a consumer (not shown), such as a fuel cell or a gas-powered combustion engine, and ensures that a predetermined maximum pressure for the consumer is not exceeded. Details of the distribution device 100 are shown in more detail in Fig. 2. The distribution device 100 includes a check valve CV, which is connected between the refueling port 110 and the pressure vessel port 130. The check valve CV can also be referred to as a check valve. The flow direction is towards the pressure vessel port 130, so that refueling is possible due to overpressure at the refueling port 110. In this case, the check valve CV opens, allowing refueling to take place.

[0026] A storage solenoid valve (SSV) is connected between the pressure vessel connection 130 and the discharge port 120. This valve can be specifically designated as a storage solenoid valve. It is electrically controlled and typically closed during refueling. It opens when gaseous fuel is to be transferred from the pressure vessels 30 to the consumer (not shown). Internally, it establishes a fluidic connection between the pressure vessel connection 130 and the discharge port 120. A bypass valve (BV) is connected in parallel to this storage solenoid valve (SSV) and can perform essentially the same connection function. However, it is manually controlled, not electrically, and allows for the emptying of the pressure vessels 30 or even continued operation of the consumer (not shown) in the event of a malfunction of the storage solenoid valve (SSV).

[0027] A fluidic connection 140 is also connected between the refueling port 110 and the extraction port 120. This connection contains another check valve CV*, the flow direction of which points towards the extraction port 120. A throttle DR is connected in series with the second check valve CV*, which is designed as a local constriction in the fluidic connection 140. During refueling, the fluidic connection 140 increases the pressure not only in the pressure vessels 30, i.e., at the pressure vessel port 130, but also at the extraction port 120 and in the directly connected piping system, specifically up to the pressure reducer 20. This ensures that a pressure is established in this piping system during refueling that corresponds to the pressure prevailing in the pressure vessels 30 after the refueling process.When the extraction valve SSV is opened to draw off gaseous fuel, no rapid pressure surge occurs at the pressure reducer 20; instead, the pressures are essentially identical on both sides of the extraction valve SSV. This can, in particular, increase the service life of the pressure reducer 20.

[0028] Reference symbol list

[0029] 10 Supply system

[0030] 12 Refueling line

[0031] 15 refueling nozzles

[0032] 20 pressure reducers

[0033] 30 pressure vessels

[0034] 35 Connecting cable

[0035] 100 distribution equipment

[0036] 110 Refueling connection

[0037] 120 extraction connection

[0038] 130 Pressure vessel connection

[0039] 140 fluidic compound

[0040] CV check valve

[0041] CV* additional check valve

[0042] DR Throttle

[0043] SSV extraction valve

[0044] BV Bypass Valve

Claims

Claims 1. Distribution device (100) for gaseous fuel, comprising: - a refueling connection (110) for connecting a refueling line (12), - a withdrawal connection (120) for connecting a pressure reducer (20) or a consumer of the gaseous fuel, - a pressure vessel connection (130) for connecting one or more pressure vessels (30) for storing gaseous fuel, - a withdrawal valve (SSV) that is electrically switchable and connects the pressure vessel connection (130) to the withdrawal connection (120), - a non-return valve (CV) which connects the refueling port (110) to the pressure vessel port (130), and whose flow direction points towards the pressure vessel port (130), and - a fluidic connection (140) which connects a point between the withdrawal valve (SSV) and the withdrawal port (120) with a point between the refueling port (110) and the check valve (CV) for conveying gaseous fuel from the refueling port (110) to the withdrawal port (120).

2. Distribution device (100) according to claim 1, further comprising a further check valve (CV*) which is arranged in the fluidic connection (140) and whose flow direction points towards the extraction port (120).

3. Distribution device (100) according to claim 1 or 2, further comprising a throttle (DR) which is arranged in the fluidic connection (140).

4. Valve device according to one of the preceding claims, further comprising a switchable valve which is arranged in the fluidic connection (140).

5. Distribution device (100) according to claim 4, wherein the switchable valve is electrically switchable.

6. Distribution device (100) according to one of the preceding claims, further comprising a bypass valve (BV) which switchably connects a point between the withdrawal valve (SSV) and the withdrawal port (120) with a point between the pressure vessel port (130) and the check valve (CV).

7. Distribution device (100) according to claim 6, wherein the bypass valve (BV) is mechanically switchable.

8. Distribution device (100) according to one of the preceding claims, further comprising a pressure sensor for measuring a pressure at the extraction port (120) and / or comprising a pressure sensor for measuring a pressure at the refueling port (110).

9. Supply system (10) for supplying a consumer with gaseous fuel, comprising: - a distribution device (100) according to one of the preceding claims, - a refueling nozzle (15) which is fluidically connected to the refueling port (110), - one or more pressure vessels (30) which are fluidically connected to the pressure vessel connection (130), and - a pressure reducer (20) which is connected to the extraction port (120).

10. Supply system (10) according to claim 9, which has only one pressure sensor.

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