Method for operating a system component of a gas storage system, system component of a gas storage system, controller and vehicle

Abstract

The invention relates to a method for operating a fluid-flowable component of a fluid storage system. The invention further relates to a fluid-flowable component of a gas storage system. It also relates to a controller for controlling the system component and to a vehicle with a gas storage system that includes the fluid-flowable component operated by the method according to the invention. The method according to the invention for operating a fluid-flowable component of a fluid storage system of a vehicle, wherein the fluid-flowable component is heatable, is characterized in that the heating of the fluid-flowable component is controlled in a situation-dependent manner, taking into account an expectation of a future change in the situation.

Description

[0001] The invention relates to methods for operating a component of a storage system for fluids through which a fluid can flow. The fluid can be liquid or gaseous. The component through which the fluid can flow can be, for example, a valve or a pressure reducer. The storage system can, for example, have a pressure vessel for a gaseous fluid, for example gaseous hydrogen. The component can, for example, be part of a filling and / or removal system for such a pressure vessel. The invention further relates to a component of a gas storage system through which a fluid can flow. The invention further relates to a controller for controlling the system component and to a vehicle with a gas storage system that has the component through which a fluid can flow and is operated using the method according to the invention.

[0002] The market for pressure vessels, particularly those reinforced with fiber composite material (FVM), is growing continuously. The increasing production of natural gas and fracking gas necessitates storage in pressure vessels, especially in countries without a corresponding pipeline network. In addition, the automotive sector is working hard on the development of fuel cell vehicles, in which the fuel, in the form of gaseous hydrogen, is to be stored under high pressure in pressure vessels. This applies not only to automobiles, but also to rail, aircraft, and watercraft. Applications are even conceivable in spacecraft. Lightweight pressure vessels are desired for transporting pressure vessels because transporting heavy pressure vessels consumes unnecessary amounts of energy and therefore results in excessively high transport costs.

[0003] Currently used cylindrical fiber-reinforced pressure vessels have a reinforcement layer made of FVM (fiber reinforced plastic) embedded in a matrix material, which is wound as an outer layer onto an inner container (the so-called liner) of the pressure vessel, which acts as the winding core. While the inner container, for example, guarantees the gas-tightness of the pressure vessel, the reinforcement layer made of FVM gives the pressure vessel the necessary mechanical stability. Type 3 pressure vessels have a metallic inner container (metallic liner), e.g. made of aluminum or steel; in Type 4 pressure vessels, the non-load-bearing inner container (liner) is made of a plastic. The plastic liners are usually manufactured by blow molding, rotomolding, or welding individual components.Due to the manufacturing processes, the materials commonly used are thermoplastics such as polyamides or polyethylenes, especially high-density polyethylene.

[0004] A metal boss serves as a connection point for a valve for filling and / or discharging gas, or as the end piece of a Type 4 vessel. It can then be designed as a closed boss. The boss's outer diameter is significantly smaller than the outer diameter of the liner.

[0005] The pressure vessels must withstand very high internal pressure. Currently, for example, automobile hydrogen tanks are filled with a pressure of approximately 700 bar. In particular, the pressure vessels must not burst even in the event of a crash. Therefore, such pressure vessels are designed with a cylindrical center section sealed on both sides with so-called pole caps. The cylindrical center section and pole caps are wound with a fiber-reinforced polymer (FVM) as a reinforcement layer. For example, the reinforcement layer is manufactured using the filament winding process, which winds the pressure vessels in a single operation. In other words, the fibers are wound onto the plastic liner in circumferential and cross layers or helical layers in a single operation.

[0006] Since, on the one hand, the pressures in a pressure vessel of this type, as described above, can be very high and corresponding filling or extraction valves must be able to open against this pressure, and on the other hand, the space available for installation in the boss is very limited, valves with correspondingly large coils cannot be used to generate the required opening force. Therefore, pilot valves are usually used. A pilot valve operates according to the differential pressure or servo principle and uses the pressure of the medium to open and close the valve seat. The pilot system acts as an amplifier, so that fluids with high volume flows at higher pressures can be controlled using a magnet with a relatively small coil and thus low force.In the case of the previously described pressure vessels for hydrogen, the flow cross-sections for the gas in the pilot valve are typically less than 0.1 mm², and in the main valve between approximately 2 mm² and 3 mm². If the gas with which the pressure vessel is to be filled, or with which the pressure vessel is already filled, contains even a small amount of water, there is a risk that this water will sublimate in these small cross-sections at correspondingly low temperatures, thus making valve control difficult or even impossible. Hydrogen always contains a certain residual amount of water.

[0007] When estimating the gas temperature in these small cross-sections, it must be remembered that when a gas expands, internal energy is converted into volume work, causing the temperature of the expanding gas to drop. The same applies when the fluid changes from a liquid to a gaseous state through expansion. Thus, critically low temperatures can arise during filling or gas withdrawal, even at moderate ambient temperatures above freezing. Critical gas temperatures are easily reached, particularly at ambient temperatures well below freezing. For example, when hydrogen is withdrawn from a pressure vessel in a hydrogen-powered vehicle at an ambient temperature of -30°C, a hydrogen temperature of -60°C or lower can easily be reached.

[0008] US Pat. No. 9,851,020 B2 discloses a valve comprising a body with an inlet at a first end of the body and an outlet at a second end of the body. A first electrical resistance heating element is disposed in the inlet and heats a first fluid source to a temperature above 0°C. A second electrical resistance heating element is located in the outlet and heats a second fluid source to a temperature above 0°C.

[0009] A heated outlet valve for a hydrogen storage tank is known from DE 10 2007 041 882 B4. The hydrogen storage tank has a cylindrical adapter and a valve through which the hydrogen can be withdrawn from the tank. A generator is positioned in the tank, which generator has a rotating element positioned in a channel running through the adapter. When hydrogen is withdrawn from the tank, the mass flow of hydrogen causes the rotating element to rotate, which causes the generator to generate electricity. One or more resistance heating elements are positioned in the adapter, preferably adjacent to the tank seals, which receive an electrical current from the generator, which heats the resistance heating element and the adapter to increase the temperature of the adapter and the hydrogen withdrawn from the tank.

[0010] DE 10 2005 049 253 B4 discloses a heat-sensitive vent valve for a cryogenic tank. The cryogenic tank is intended to store liquid hydrogen. In one embodiment, the cryogenic valve comprises a valve plate attached to a valve body by a spring. The spring presses the valve plate against a valve seat to prevent hydrogen from flowing through the cryogenic valve when the valve is in a closed position. A resistance heater is positioned adjacent to the valve plate. An electric current applied to the heater causes the device to expand, which presses the device against the valve plate and against the spring bias to move the valve plate away from the valve seat and allow hydrogen to flow through.The low-temperature valve may be designed so that the heating device does not come into direct contact with the hydrogen.

[0011] The disadvantages of the resistance heating elements used in the state of the art are their high power consumption and the large amount of space they require.

[0012] In particular, since commercial vehicles in high northern or southern latitudes are also to be powered by hydrogen, ensuring the operation of the filling and / or removal system of a generic pressure vessel is highly desirable, especially if this can be achieved with relatively little effort.

[0013] The aim was to ensure the most economical operation possible and to keep the space required as small as possible.

[0014] The object of the invention is to provide a method for operating a heatable component through which a fluid can flow, in particular a heatable filling and / or dispensing valve of a fluid storage system of a vehicle, which improves the prior art or provides an alternative to it. A further object of the invention is to provide a heatable component through which a fluid can flow, in particular a heatable filling and / or dispensing valve of a fluid storage system. A further object of the invention is to provide a vehicle with a fluid storage system that can be operated using the method according to the invention.

[0015] The first object of the invention is achieved by a method according to independent claim 1. Advantageous further developments of the method emerge from claims 2 to 10. The second object of the invention is achieved by a device according to the independent claim 11. Advantageous further developments of the device emerge from claims 12 to 14. The third object of the invention is achieved by a controller according to claim 15, while the last object of the invention is achieved by a vehicle according to claim 16.

[0016] The method according to the invention for operating a component of a fluid storage system of a vehicle through which a fluid can flow, wherein the component through which the fluid can flow is heatable, is characterized in that the control of the heating of the component through which the fluid can flow is situation-dependent.

[0017] The following terminology is used to explain this: flow-through component of a fluid storage systemrefers to all components of a fluid storage system through which the fluid can flow. Such components can include valves or pressure reducers, for example.

[0018] Under a vehicle This term refers to any device that can transport goods or people from one place to another. In particular, this term includes passenger cars or commercial vehicles, such as trucks, or work machines such as excavators, rail vehicles, or even aircraft or spacecraft.

[0019] Under a Fluid storage system is understood to mean a system comprising multiple components capable of storing a fluid, particularly a gaseous fluid. The fluid can be stored, in particular, under high pressure, i.e., a pressure significantly higher than ambient pressure. A core component of such a fluid storage system is therefore a pressure vessel.

[0020] Under heated or heating is understood here that the component through which a fluid can flow is changed in its temperature, in particular heated, in such a way that ice crystal formation in the fluid flowing through is prevented. Since ice crystal formation will begin in the smallest flow cross-section of the component through which a fluid can flow, the terms heated or heating in particular a temperature change, in particular heating, of the smallest flow cross-section.

[0021] Under steeringHere, the term "control" is understood as influencing the behavior of a system. In particular, the term "control" is understood as a generic term and refers to control in the narrower sense, i.e., influencing the behavior of a system without detecting and returning a state, as well as to closed-loop control, in which the behavior of a system is influenced by detecting and returning a state, so that changes in the system's state caused by disturbances can be counteracted.

[0022] Under situation-dependentis understood here that the heating is started, maintained and / or stopped by a specific situation. The situation can be characterized by a certain ambient temperature, a certain route, certain weather events, or similar, whereby the situation can exist currently or is expected for a future point in time. Information about the current location of the vehicle, the future location of the vehicle, i.e. the planned route, current and / or future time data, i.e. date and time, can be used to determine the situation. GPS and / or telemetry data, data from navigation software and / or from a timetable, etc. can be used to obtain this information.

[0023] The method according to the invention makes it possible to minimize or even prevent the formation of ice crystals in the fluid, particularly when the vehicle moves from a non-critical situation into a critical situation. A non-critical situation is characterized by an ambient temperature or a temperature at critical components at which the formation of ice crystals is very unlikely. A situation is considered critical if, in contrast, the formation of ice crystals in the fluid is likely. For example, the probability of ice crystals forming in hydrogen increases significantly at low temperatures, particularly at ambient temperatures of -20°C and below. In this case, it is particularly advantageous if the heating of the component through which the fluid flows is started early, before the situation becomes critical.Otherwise, a large heating capacity would have to be installed to ensure that the already critical or supercritical temperature is quickly raised above the critical threshold again. Compared to constant, situation-independent heating of the component through which the fluid flows, the method according to the invention minimizes energy consumption.

[0024] A further advantage of the method according to the invention is that the component through which the fluid can flow usually contains soft seals which can lose their elasticity at low temperatures, but which are heated with the method according to the invention when a critical situation threatens and thus better fulfill their sealing function.

[0025] For the space reasons described above, pilot valves are often used in pressure vessels for hydrogen, for example. The flow cross-sections for the gas in the pilot valve are usually less than 1 mm². In the gases used, especially in hydrogen, the presence of small amounts of residual water cannot be prevented, or cannot be prevented with reasonable effort. There is therefore a risk that this water will sublimate in the small cross-sections at correspondingly low temperatures and make the functions of the component through which the fluid flows, for example valve movement, difficult or even impossible. The formation of ice crystals can be prevented by heating the component through which the fluid flows.

[0026] In an advantageous embodiment of the method according to the invention, the heating of the component through which the fluid flows is controlled depending on the situation, taking into account the expectation of a future change in the situation. By taking into account the expectation of a future change in the situation, the heating of the component through which the fluid flows can be started earlier, particularly in the event of a rapid change to a critical state, thus even better preventing the situation from becoming critical.

[0027] In an advantageous embodiment of the method according to the invention, the heating of the component through which the fluid flows is changed if a future change in the situation indicates that the temperature of the fluid flowing through the component will fall below a permissible level and ice crystals will form. If the temperature falls below a permissible level, ice crystals can form, for example, or a sealing material, for example on a boss / OTV or another component, can change its properties in an impermissible or undesirable way. For example, a vehicle can quickly go from a non-critical situation to a critical one. For example, a vehicle that is being driven in cold but still non-critical ambient temperatures can drive uphill due to the route guidance, which can cause the ambient temperature to drop.It is advantageous if the heating of the component through which the fluid flows starts before the situation becomes critical, i.e., before the ambient temperature falls into the critical range. By incorporating an expectation of a future change in the situation, the heating of the component through which the fluid flows can be started accordingly early, thus preventing the development of a critical temperature in the flowing fluid.

[0028] In a further advantageous embodiment, a future change in the situation is estimated using temperature data and / or GPS data.

[0029] Under GPS data This refers to data about the current location. Thus, knowing the current GPS data and thus the current location of a vehicle can be used to estimate a future change in the situation.

[0030] Furthermore, it has proven advantageous if a future change in the situation is additionally estimated using data from navigation software.

[0031] Under a Navigation software This refers to a computer-based program that calculates a route to a specified destination, taking the current location into account. Additional parameters, such as vehicle-specific parameters such as vehicle weight or other vehicle characteristics that may affect the route to be calculated, can be taken into account for the calculation.

[0032] This makes it possible, for example, to detect gradients on the further route and thus to determine the risk of a critical situation occurring, so that the heating of the component through which the fluid flows can be started at an early stage.

[0033] In a further advantageous embodiment, the temperature of the component through which the fluid flows and / or of the fluid flowing through is detected. In particular, it has proven advantageous if the temperature of the component through which the fluid flows and / or of the fluid flowing through is detected at the smallest flow cross-section and this temperature is used to regulate the heating of the component through which the fluid flows, since the risk of ice crystal formation is greatest at this point.

[0034] This involves captureThis means not only measuring, but also predicting. Temperatures at critical points cannot usually be measured on-site, but can be predicted using models and / or tables based on measured values ​​recorded at accessible locations. The models must incorporate relevant physical effects, such as flow resistance, expansion-induced cooling, etc.

[0035] Heating can be done electrically, for example via a resistance heater such as a heating cartridge or a heating pad, or by induction.

[0036] In an advantageous embodiment, process waste heat is used to heat the component through which the fluid can flow, wherein it has proven particularly advantageous if the process waste heat originates from an energy conversion process.

[0037] Under a Energy conversion processis understood here as a process in which one form of energy is converted into another. For example, the combustion process in an internal combustion engine is such an energy conversion process in which chemical energy from a fuel, such as hydrogen, is converted into kinetic energy, for example for driving a vehicle. The so-called cold combustion, in which the chemical energy of hydrogen is converted into electrical energy in a fuel cell, is also such an energy conversion process. These processes are exothermic, releasing heat, which is referred to here as Process waste heat is called.

[0038] This means that energy can be used to heat the component through which the fluid flows, which would otherwise be released unused into the environment as process waste heat during the energy conversion for driving a vehicle.

[0039] In a further advantageous embodiment, the process waste heat originates from an electromagnetic coil used to drive an electromagnetic valve of the component through which a fluid flows, in particular to drive a piston of a pilot valve. The coil can be dimensioned differently accordingly, for example, oversized, i.e., larger than required for the valve drive, so that it produces more process waste heat. This eliminates any measures that might otherwise be required to transport the required heat energy to the area of ​​the smallest flow cross-section of the flowing fluid.

[0040] In an alternative or cumulative embodiment, the process heat is transported to the component through which a fluid flows via a heat transfer fluid. The process heat can originate from an energy conversion process. The heat transfer fluid can be, for example, water, oil, or even a gas, such as air.

[0041] A heatable component of a fluid storage system of a vehicle through which a fluid can flow according to the invention is characterized in that the component through which a fluid can flow is intended to be heated by process waste heat, wherein the component through which a fluid can flow is heatable via heat conduction.

[0042] In one embodiment, the component through which a fluid can flow has a temperature control channel through which a heat transfer fluid can be conducted.

[0043] It has proven particularly advantageous if the temperature control channel is positioned in such a way that the smallest cross section through which the fluid can flow can be temperature controlled.

[0044] The smallest cross-section through which the fluid can flow is usually in the pilot valve circuit, whereby in valves in pressure vessels for hydrogen the flow cross-sections for the gas in the pilot valve are usually less than 1 mm², and in the main valve between approximately 2 mm² and 3 mm². The risk of ice crystal formation is therefore particularly high in the pilot circuit, so heating is particularly advantageous here. For this purpose, a heat transfer fluid, e.g. water or a heat transfer oil, heated by the cooling circuit of an internal combustion engine or a fuel cell, can be passed through a temperature control channel which is arranged as close as possible to the smallest cross-section through which the fluid can flow.

[0045] In an alternative or cumulative embodiment, the component through which a fluid flows comprises a solenoid valve with a coil and an armature. Process waste heat generated by the coil during operation can be introduced into the component through which a fluid flows via the armature in such a way that the smallest cross-section through which the fluid flows can be tempered. The coil can be dimensioned larger than would be required for the valve drive, so that it produces more process waste heat. This eliminates any additional measures that might otherwise be required to transport the required heat energy to the area of ​​the smallest flow cross-section of the flowing fluid.The armature of an electromagnetically driven valve can be connected in a heat-conducting manner, in particular in one piece, to the control piston of the pilot valve, so that the process waste heat of the drive coil is conducted directly to the smallest cross section through which the fluid can flow.

[0046] A controller according to the invention for controlling heating of the component through which the fluid can flow is provided to control heating of the component through which the fluid can flow in a situation-dependent manner, taking into account an expectation of a future change in the situation according to one of claims 1 to 10. ControllerThis refers to a device that controls the heating of the component through which the fluid flows, depending on the situation, taking into account the expectation of a future change in the situation. For this purpose, parameters such as current temperatures, GPS data of the current vehicle position, data from a navigation program, or similar, can be made available to the controller. Furthermore, the controller can have access to data representing a critical situation; in particular, such data can contain temperature thresholds.

[0047] A vehicle according to the invention has a fluid storage system with a heatable component through which a fluid can flow, wherein the component through which a fluid can flow is intended to be heated by process waste heat, wherein the component through which a fluid can flow is heatable via heat conduction, wherein the vehicle further comprises a controller according to the invention.

[0048] Further advantages, special features and expedient developments of the invention emerge from the subclaims and the following representation of preferred embodiments with reference to the figures.

[0049] It shows: Fig. 1 the inventive method in a schematic flow diagram.

[0050] Fig. 1shows the inventive method 100 for a vehicle in a schematic flow diagram. The method steps 110, 120, 130, 140, 150 run in the inventive controller 300. In step 110, a data query is carried out regarding the actual temperature of the vehicle's surroundings, the temperatures of the gas and the components, possibly based on model assumptions, the further planned route, and the weather forecast, in particular the predicted air temperatures for the further planned route. The actual temperature of the vehicle's surroundings can be retrieved from a vehicle-mounted temperature sensor. The weather forecast can be retrieved from corresponding databases, with this query being carried out online, for example via the Internet, or offline, for example from weather forecast data fed into the controller 300 before the start of the journey.The further planned load profile, which may include not only the route but also speed limits, traffic jam forecasts, etc., can be queried from navigation software. In step 120, the data from the previous query is processed. A decision is made as to whether the recorded data make a change in the situation appear likely. If no change in the situation is expected, the process starts again with step 110. If, on the other hand, a change in the situation is identified as likely, the decision is made in step 130 that the change in the situation makes it likely that the temperatures at relevant component positions will remain in a range or change to a range that is to be regarded as critical. In step 140, a check is made as to whether the heating of the component 200 through which a fluid can flow is active.If not, the heating of the component 200 through which a fluid can flow is switched on in step 150, and then the process jumps to step 110 to restart the process. If the heating of the component 200 through which a fluid can flow is already active, the process jumps directly from step 140 to step 110 to restart the process.

[0051] For example, the evaluation of the further planned route in step 130 could reveal that the route will climb sharply in the near future, while the weather forecast data indicates that the air temperature will decrease sharply over the further planned route, so that the risk of ice crystal formation in the component 200 through which a fluid flows increases significantly. Therefore, if the decision is that a change in the situation toward critical appears likely, heating of the component 200 through which a fluid flows is started in step 150.

[0052] If the decision is made in step 130 that the change in situation makes it likely that the temperatures at relevant component positions will remain within a range or change to a range that is considered non-critical, a check is made in step 160 to determine whether the heating of the component 200 through which a fluid can flow is active. If not, the heating of the component 200 through which a fluid can flow is stopped in step 170, and the process then jumps to step 110 to restart the process. If the heating of the component 200 through which a fluid can flow is already deactivated, the process jumps directly from step 140 to step 110 to restart the process.

[0053] The embodiments shown here are merely examples and should therefore not be considered limiting. Alternative embodiments contemplated by those skilled in the art are equally encompassed within the scope of the present invention. List of reference symbols:

[0054] 100Procedure 110Data query 120Data processing, decision as to whether data indicate a change in the situation is likely 130Data processing, decision as to whether temperatures at the relevant component positions are likely to remain or become critical 140Decision as to whether the heater is switched on 150Switching on the heater 160Decision as to whether the heater is switched on 170Switching off the heater 200Component through which a fluid can flow 300Controller

Claims

1. Method (100) for operating a component (200) of a fluid storage system of a vehicle through which a fluid can flow, wherein the component (200) through which the fluid can flow is heatable, characterized by that the control of the heating of the component (200) through which the fluid flows is carried out depending on the situation.

2. Method (100) according to claim 1, characterized by that the control of the heating of the component (200) through which the fluid flows is carried out taking into account an expectation of a future change in the situation.

3. Method (100) according to one of the preceding claims, characterized by that the heating of the component (200) through which the fluid can flow is changed (150, 170) if a future change in the situation is expected to result in the fluid flowing through the component (200) falling below a permissible temperature 4. Method (100) according to one of the preceding claims, characterized by that a future change in the situation is estimated using temperature data and / or GPS data.

5. Method (100) according to claim 4, characterized by that a future change in the situation is additionally estimated using data from navigation software.

6. Method (100) according to one of the preceding claims, characterized by that the temperature of the component (200) through which the fluid can flow and / or of the fluid flowing through is detected, in particular at the smallest flow cross-section, and this temperature is used to control the heating of the component through which the fluid can flow.

7. Method (100) according to one of the preceding claims, characterized by that Process waste heat is used to heat the component (200) through which a fluid can flow.

8. Method (100) according to claim 7, characterized by that the process waste heat comes from an energy conversion process.

9. Method (100) according to claim 8, characterized by that the process waste heat originates from an electromagnetic coil which is used to drive an electromagnetic valve of the component (200) through which a fluid can flow.

10. Method (100) according to claim 9, characterized by that the electromagnetic coil is dimensioned differently than that required for driving the electromagnetic valve of the component (200) through which a fluid can flow.

11. Method (100) according to one of claims 7 to 10, characterized by that the process waste heat is transported via a heat transfer fluid to the component (200) through which a fluid can flow.

12. Heatable component (200) of a fluid storage system of a vehicle through which a fluid can flow, characterized by thatthe component (200) through which a fluid can flow is intended to be heated by process waste heat, wherein the component (200) through which a fluid can flow is heatable by heat conduction.

13. Heatable component (200) through which a fluid can flow of a fluid storage system of a vehicle according to claim 12, characterized by that the component (200) through which a fluid can flow has a temperature control channel through which a heat transfer fluid can be conducted.

14. Heatable component (200) through which a fluid can flow of a fluid storage system of a vehicle according to claim 13, characterized by that the temperature control channel is positioned in such a way that the smallest cross-section through which the fluid can flow can be temperature controlled.

15. Heatable component (200) through which a fluid can flow of a fluid storage system of a vehicle according to one of claims 12 to 14, characterized by thatthe component (200) through which a fluid can flow has a solenoid valve with a coil and an armature, wherein process waste heat produced by the coil during operation can be introduced into the component (200) through which a fluid can flow via the armature in such a way that the smallest cross section through which the fluid can flow can be tempered.

16. Controller (300) for controlling heating of the component (200) through which the fluid can flow, characterized by that the controller (300) is provided to control heating of the component (200) through which the fluid can flow in a situation-dependent manner, taking into account an expectation of a future change in the situation according to one of claims 1 to 11.

17. Vehicle, characterized by that the vehicle comprises a fluid storage system with a heatable component (200) through which a fluid can flow according to one of claims 12 to 15 and a controller (300) according to claim 16.

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