Control unit and method for pressure vessel valves used in operating pressure vessels

Abstract

According to the present invention, the technology disclosed herein relates to a control unit (150) for a pressure vessel system (100) including at least one pressure vessel (110, 120) having a pressure vessel valve (206) configured to introduce fuel (104) from the pressure vessel (110, 120) into an extraction line (113, 123) for supplying an energy converter (103). The control unit (150) is configured to determine the existence of an operating mode of reduced power of the energy converter (103), wherein, in the reduced power operating mode, the mass flow of fuel for supplying the energy converter (103) is less than or equal to a predetermined mass flow threshold. The control unit (150) is also configured to cause the pressure vessel valve (206) to be intermittently opened during the implementation of the reduced power operating mode, so as to correspondingly introduce an inflow of fuel (104) from the pressure vessel (110, 120) into the extraction line (113, 123).

Description

Technical Field

[0001] The technology disclosed herein relates to a pressure vessel system having one or more pressure vessels, such as for a motor vehicle. Furthermore, the technology disclosed herein relates to a method for using a pressure vessel valve for operating such a pressure vessel system and a corresponding control unit. Background Technology

[0002] Motor vehicles may have fuel cells that generate electricity from fuel, such as hydrogen, for the operation of the vehicle, particularly for propulsion. The fuel may be stored in at least one pressure vessel in the vehicle. The fuel can be directed from the pressure vessel to the vehicle's fuel cell via fuel lines by opening a valve, particularly a so-called on-tank valve (OTV).

[0003] After the vehicle's fuel cell has finished operating, it is usually necessary to ensure that the valves of the vehicle's pressure vessel are reliably closed to prevent fuel from accidentally escaping from the pressure vessel. Summary of the Invention

[0004] A preferred objective of the technology disclosed herein is to reduce or eliminate at least one drawback of known solutions or to propose alternative solutions. A preferred objective of the technology disclosed herein is to achieve effective and reliable testing of the sealing performance of valves in the pressure vessel system of a vehicle.

[0005] According to one aspect, a control unit for a pressure vessel system, particularly for a pressure vessel system for motor vehicles (e.g., for passenger cars, motorcycles, commercial vehicles, etc.), is described. Here, the pressure vessel system is typically used to store fuels that are gaseous under ambient conditions. The pressure vessel system can be used, for example, in motor vehicles that operate using compressed (also known as compressed natural gas or CNG) or liquefied (also known as liquefied natural gas or LNG) natural gas or hydrogen (especially H2) as fuel. The pressure vessel system is typically fluidly connected to at least one energy converter configured to convert the chemical energy of the fuel into one or more other forms of energy.

[0006] This pressure vessel system includes at least one pressure vessel, particularly a composite outer packaging pressure vessel. The pressure vessel may be, for example, a cryogenic pressure vessel or a high-pressure gas vessel.

[0007] High-pressure gas vessels are constructed to sustainably store fuel at a nominal operating pressure (also known as NWP) of at least 350 bar (= overpressure relative to atmospheric pressure) or at least 700 bar at ambient temperature. Cryogenic pressure vessels are suitable for storing fuel at the aforementioned operating pressures or even at temperatures significantly below the operating temperature of the motor vehicle (e.g., exceeding 50 Kelvin or exceeding 100 Kelvin).

[0008] The pressure vessel system described herein includes at least one pressure vessel with a pressure vessel valve configured to direct (gaseous) fuel from the pressure vessel into an extraction line for supplying an energy converter. Typically, a pressure converter is arranged between the extraction line and the energy converter, which is configured to convert fuel having a relatively high pressure (e.g., 100 bar or higher) from the extraction line into fuel having a relatively low pressure (e.g., 2 bar or lower).

[0009] Pressure vessel valves can be so-called on-tank valves (OTVs). A combination of a solenoid-operated valve, a manually operated valve, and possibly a thermal relief device (TPRD) is commonly referred to as an on-tank valve (OTV). Solenoid-operated and manually operated valves can, in particular, be connected in series, where one or both can be separate tank shut-off valves.

[0010] An energy converter is configured to convert the chemical energy of fuel into one or more other forms of energy, such as electrical energy and / or kinetic energy. An energy converter may be, for example, an internal combustion engine or a fuel cell system or a fuel cell stack having at least one fuel cell.

[0011] The control unit is configured to determine the existence of an operating mode where the energy converter experiences reduced power. Here, the reduced power operating mode can be an operating mode in which the mass flow of fuel supplied to the energy converter (through a pressure vessel valve and / or through an extraction line) is less than or equal to a predetermined mass flow threshold. The reduced power operating mode may differ from the power operating mode, in which the mass flow of fuel supplied to the energy converter is greater than the mass flow threshold. The power operating mode can, for example, be used to drive a propulsive motor vehicle.

[0012] Pressure vessel systems can, for example, be designed for nominal mass flow (for power operation mode). The mass flow threshold can be 10% or less of the nominal mass flow.

[0013] In a preferred example, the fuel includes hydrogen, particularly hydrogen. Furthermore, the energy converter includes at least one fuel cell (especially a fuel cell stack). Additionally, a power-reducing operating mode may include freeze conditioning of the fuel cell, particularly this freeze conditioning. During freeze conditioning, fuel may be used to flush one or more fuel cells, thereby removing residual water from the one or more fuel cells.

[0014] The control unit is also configured to intermittently and / or pulse-wise open the pressure vessel valve during the implementation of a power-reduced operating mode, thereby directing the inflow of fuel from the pressure vessel into the extraction line accordingly. In other words, the pressure vessel valve can only be opened temporarily (for defined pulse durations, respectively) to temporarily or pulse-wise direct fuel from the pressure vessel into the extraction line.

[0015] Intermittent operation of the pressure vessel valve allows the fuel pressure in the extraction line to be adjusted to a value lower than the fuel pressure inside the pressure vessel, thereby reliably verifying the sealing performance of the pressure vessel valve, especially based on the time development of the fuel pressure in the extraction line (when the pressure vessel valve is closed or should be closed).

[0016] Therefore, the control unit can be configured (especially after the power reduction operating mode ends) to determine (e.g., using a pressure sensor in the extraction line) line sensor data regarding the (fuel) pressure in the extraction line. This line sensor data can be detected in particular when the pressure vessel valve should close (e.g., after the power reduction operating mode ends). Whether the pressure vessel valve is sealing can then be reliably determined based on the line sensor data (especially based on the time-varying development of the fuel pressure in the extraction line).

[0017] Furthermore, the control unit can be configured to determine the presence of a power operation mode for the energy converter, wherein, in the power operation mode, the mass flow of fuel supplied to the energy converter is greater than a predetermined mass flow threshold. The pressure vessel valve can then be made to remain permanently open during the (entire) implementation of the power operation mode to direct fuel from the pressure vessel into the extraction line.

[0018] By keeping the pressure vessel valve open for an extended period, a reliable fuel supply to the energy converter can be ensured. On the other hand, keeping the pressure vessel valve open for an extended period usually results in the fuel pressure in the extraction line corresponding to the internal pressure in the pressure vessel (therefore, after closing the pressure vessel valve, the sealing performance of the pressure vessel valve cannot usually be determined based on line sensor data regarding the pressure in the extraction line).

[0019] The control unit can be configured to intermittently open the pressure vessel valve during the (entire) implementation of the power reduction mode, ensuring that the pressure in the extraction line does not exceed a predetermined upper pressure limit (during the entire implementation of the power reduction operation mode). Here, the upper pressure limit is preferably less than the internal pressure in the pressure vessel (e.g., a certain offset value, such as approximately 10% or more, or 50-60 bar). Alternatively or additionally, the control unit can be configured to intermittently open the pressure vessel valve during the (entire) implementation of the power reduction operation mode, ensuring that the pressure in the extraction line is always at least a predetermined offset value less than the internal pressure in the pressure vessel. This operation of the pressure vessel valve allows for a particularly reliable verification of its sealing performance (during and / or immediately following the power reduction operation mode).

[0020] The control unit can be configured to determine pipeline sensor data regarding the pressure in the extraction line during a reduced-power operating mode (repeatedly, especially periodically, if necessary). Power sensor data can be determined particularly when the pressure vessel valve is closed or should be closed. The pressure vessel valve can then be reliably opened intermittently based on the pipeline sensor data. Specifically, the control unit can be configured to detect when the pressure in the extraction line reaches or falls below a lower pressure limit (e.g., 100 bar) based on the pipeline sensor data. An energy pulse can then be generated in response to this to intermittently open the pressure vessel valve (for a defined pulse duration). Therefore, a reliable fuel supply to the energy converter can be achieved even during intermittent operation of the pressure vessel valve.

[0021] The control unit can be configured to (repeatedly, especially periodically, as necessary) determine status data related to various current states of the pressure vessel system. Status data may, for example, include information about the current pressure in the extraction lines (especially line sensor data). Alternatively or supplementarily, status data may include information about the current pressure in the pressure vessel (especially sensor data). Alternatively or supplementarily, status data may include information about the current temperature of the fuel (especially sensor data).

[0022] The control unit can also be configured to generate energy pulses related to status data to intermittently open the pressure vessel valve. In particular, one or more parameters of the energy pulses can be adjusted based on the status data. These parameters may include: the current intensity (especially a current pulse) generated to open the pressure vessel valve; the voltage value (especially a voltage pulse) generated to open the pressure vessel valve; the duration of the energy pulse; and / or the electrical power and / or energy of the energy pulse.

[0023] An energy pulse can be induced, for example, on an electromagnet in a pressure vessel valve to generate a pulsed magnetic field, through which the pressure vessel valve opens pulsedly. The power and / or energy of the energy pulse can therefore be adapted to the current state of the pressure vessel system (especially to the current pressure in the extraction line, the current pressure in the pressure vessel, and / or the pressure difference between the two pressures). This allows for precise adjustment of the pressure in the extraction line (so as to reliably verify the sealing of the pressure vessel valve).

[0024] The control unit can be configured to generate energy pulses based on status data to adjust the pressure in the extraction line to a predetermined upper pressure limit, and / or to induce a pressure increase in the extraction line by a predetermined pressure difference. Therefore, the energy pulses can also be adapted based on the pressure to be induced in the extraction line and / or based on the pressure increase to be induced. This further improves the quality of pressure adjustment in the extraction line and thus further enhances the reliability of the pressure vessel valve's sealing test.

[0025] The control unit can be configured to generate energy pulses based on predetermined characteristic data of the pressure vessel system. This characteristic data can be stored in the storage unit of the pressure vessel system. Furthermore, the characteristic data can be predetermined during experimentation.

[0026] Characteristic data can specify the parameter values ​​of one or more parameters of the energy pulse for multiple different possible state data (i.e., multiple different possible states of the pressure vessel system). Characteristic data can be determined to cause a pressure increase in the extraction line by a predetermined pressure difference and / or to a predetermined pressure upper limit, starting from the current state of the pressure vessel system indicated by the state data. By considering the predetermined characteristic data of the pressure vessel system, the adjustment quality of the pressure in the extraction line can be further improved, and thus the reliability of the sealing test of the pressure vessel valve can be further improved.

[0027] Pressure vessel valves may have a pilot seat and a main seat. Here, when the pilot seat of the pressure vessel valve is open, the fuel mass flow from the pressure vessel can be less than when the main seat is open (e.g., twice or more less). On the other hand, opening the pilot seat may cause less wear on the pressure vessel valve than opening the main seat.

[0028] The control unit can be configured to intermittently open the pressure vessel valve, such that during the (entire) implementation of a reduced-power operating mode, the main seat is at least temporarily not opened, or never opened, and / or at least temporarily or only opened. This allows for the intermittent operation of the pressure vessel valve in an effective and reliable manner to test the valve's sealing performance.

[0029] A pressure vessel system may include a first pressure vessel valve (e.g., a first pressure vessel for a pressure vessel system) and a second pressure vessel valve (e.g., a second pressure vessel for a pressure vessel system).

[0030] The control unit can be configured to at least temporarily and intermittently open the first pressure vessel valve and at least temporarily and intermittently open the second pressure vessel valve during a power reduction operation mode of the energy converter and / or during multiple successive power reduction operation modes, particularly by alternately opening the first and second pressure vessel valves. By alternately operating the different pressure vessel valves, the load on the pressure vessel valves can be reduced due to the intermittent operation, which in turn enables a reliable test of the sealing performance of the pressure vessel valves.

[0031] The control unit can be configured to determine mass flow information relating to the fuel mass flow in the energy converter. This mass flow information can be provided by the energy converter. Specifically, the energy converter can have a valve on the inlet side that adjusts, particularly regulates, the input mass flow entering the energy converter. This valve may, for example, include a proportional valve or one or more injectors. The signal provided by the valve can represent the input mass flow entering the energy converter (and therefore can be provided as mass flow information).

[0032] The device can also be configured to intermittently open the pressure vessel valve based on mass flow information during a power-reduced operating mode. This can be achieved in particular by ensuring that the fuel mass flow from the pressure vessel supplied by opening the pressure vessel valve corresponds, at least in average time, to the fuel mass flow entering the energy converter. In other words, the pressure vessel valve can be pulsed such that the output mass flow from the pressure vessel equals the input mass flow of the energy converter. This enables a particularly reliable power-reduced operating mode for the energy converter.

[0033] According to another aspect, a pressure vessel system is described, particularly for use in motor vehicles. The pressure vessel system includes at least one pressure vessel having a pressure vessel valve configured to direct fuel from the pressure vessel to an extraction line for supplying an energy converter. Furthermore, the pressure vessel system includes a control unit as described herein, configured to operate the pressure vessel valve (for intermittent operation).

[0034] According to another aspect, a (road) motor vehicle (especially a passenger car, truck, or bus) is described, which includes the pressure vessel system described herein.

[0035] According to another aspect, a method for operating a pressure vessel valve for a pressure vessel is described, wherein the pressure vessel valve is configured to direct fuel from the pressure vessel to an extraction line for supplying an energy converter.

[0036] The method includes determining an operating mode in which the power of the energy converter is reduced. In this reduced-power operating mode, the mass flow of fuel supplied to the energy converter (via a pressure vessel valve or via an extraction line) is less than or equal to a predetermined mass flow threshold. The method also includes intermittently opening the pressure vessel valve during the (entire) implementation of the reduced-power operating mode to respectively direct the inrush of fuel from the pressure vessel into the extraction line (and hereby to induce a fuel pressure in the extraction line that is less than the fuel pressure in the pressure vessel).

[0037] According to another aspect, a software (SW) program is described. This SW program can be configured to be implemented on a processor (e.g., on a vehicle control device) and thereby implement the methods described herein.

[0038] According to another aspect, a storage medium is described. The storage medium may include a working program (SW) configured to be implemented on a processor and thereby implement the methods described herein.

[0039] It should be noted that the methods, apparatuses, and systems described herein can be used not only individually but also in combination with other methods, apparatuses, and systems described herein. Furthermore, each aspect of the methods, apparatuses, and systems described herein can be combined with each other in diverse ways. In particular, the features of the claims can be combined with each other in diverse ways. Attached Figure Description

[0040] The present invention will now be described in more detail with reference to embodiments. The accompanying drawings are as follows:

[0041] Figure 1 An exemplary pressure vessel system with multiple pressure vessels is shown;

[0042] Figure 2 An exemplary valve device for a pressure vessel is shown;

[0043] Figure 3 An exemplary time-varying curve of pressure in the fuel extraction line of a pressure vessel system is shown.

[0044] Figure 4 Exemplary feature data for operating pressure vessel valves are shown; and

[0045] Figure 5 A flowchart illustrating an exemplary method for operating a pressure vessel valve is shown. Detailed Implementation

[0046] As mentioned at the beginning, the technical task to be addressed in this paper is to reliably verify the sealing of pressure vessel valves, especially at the end of operation of energy converters in vehicles, particularly fuel cells.

[0047] In this regard, Figure 1 An exemplary pressure vessel system 100 is shown, including a first pressure vessel 110 and a second pressure vessel 120. Pressure vessels 110 and 120 each have valve devices 112 and 122, respectively, through which fuel 104 can be controlled to flow into or out of the pressure vessels 110 and 120, respectively.

[0048] exist Figure 1 The pressure vessel system 100 shown includes inlet lines 111 and 121 configured to direct fuel 104 from a fuel inlet 101 to pressure vessels 110 and 120. A first supply line 111 leads to the inlet of a first valve device 112 of the first pressure vessel 110. Correspondingly, a second supply line 121 leads to the inlet of a second valve device 122 of the second pressure vessel 120. Thus, both pressure vessels 110 and 120 can be fueled from the fuel inlet 101.

[0049] The pressure vessel system 100 also includes a first extraction line 113 connected to the outlet of the first valve device 112 and a second extraction line 123 connected to the outlet of the second valve device 122. Fuel 104 can be introduced from pressure vessels 110 and 120 to pressure converter 102 through extraction lines 113 and 123. Typically, the pressure in pressure vessels 110 and 120 is higher than the operating pressure of energy converter 103 (e.g., a fuel cell or fuel cell stack). The operating pressure of energy converter 103 can be, for example, in the range of 10-20 bar. The pressure in pressure vessels 110 and 120 can be, for example, 2, 5, 10, 20 times or higher than the operating pressure of energy converter 103. Pressure converter 102 (especially a pressure regulator) can be configured to convert the pressure of fuel 104 from pressure vessels 110 and 120 into the operating pressure required by energy converter 103.

[0050] Figure 2 Exemplary valve devices 112 and 122 for pressure vessels 110 and 120 are shown. Valve devices 112 and 122 include an inlet port 201 for coupling supply lines 111 and 121 and an outlet port 203 for coupling extraction lines 113 and 123. Fuel 104 supplied through the inlet port 201 can be filtered in an inlet filter 202 to avoid or reduce contamination of the pressure vessels 110 and 120 and / or the seals of the valve devices 112 and 122.

[0051] An inflow channel 221, including an inflow port 201 for supplying fuel 104, and an outflow channel 223, including an outflow port 203 for discharging fuel 104, can be coupled to each other at a coupling point 216 and to a common channel 222. The common channel 222 can connect the coupling point 216 to the interior of pressure vessels 110, 120.

[0052] Common passage 222 may include an electrically operated valve 206. The electrically operated valve 206 may be electrically connected to a data interface 210 of valve devices 112, 122 via a data bus. A control signal can be received through data interface 210, indicating whether the electrically operated (pressure vessel) valve 206 should be open or closed. The electrically operated valve 206 may include, for example, a solenoid valve. The control signal may be provided by a control unit 150 of the pressure vessel system 100.

[0053] A check valve 215 may be arranged in parallel with the electrically operated valve 206. The check valve 215 may be configured to prevent fuel 104 from escaping from pressure vessels 110 and 120, but allows fuel 104 to be supplied to pressure vessels 110 and 120 (e.g., during refueling) by overcoming the restoring force of the check valve 215. Furthermore, the electrically operated valve 206 may be bypassed if necessary by a manual valve 207. The manual valve 207 may, for example, be manually opened by a maintenance personnel to at least partially drain fuel from pressure vessels 110 and 120.

[0054] The inflow channel 221 and the outflow channel 223 can therefore extend from the coupling point 216 to the interior of the pressure vessels 110, 120 via a common channel 222. Here, the common channel 222 can be guided by an additional manual valve 214, which can be used to manually close or open the pressure vessels 110, 120. Furthermore, the common channel 222 can be guided through an additional outflow filter 212, by which fuel 104 can be filtered before being supplied to the energy converter 103.

[0055] Valve devices 112, 122 may also include a temperature sensor 213 with an evaluation unit 208 connected to a data interface 210. This allows sensor data on the temperature of the pressure vessels 110, 120 and / or the stored fuel 104 to be provided. Valve devices 112, 122 may also include a pressure relief unit 209 (e.g., a thermal pressure relief device (TPRD)) configured to open the pressure vessels 110, 120 when a temperature threshold is reached or exceeded, thereby discharging the fuel 104 through an exhaust unit (especially an opening) 211 and thus reducing the pressure within the cavities of the pressure vessels 110, 120.

[0056] The outflow channel 223 may have a flow restriction unit 205 between the coupling point 216 and the outflow port 203, where the outflow channel 223 and the inflow channel 221 merge. The flow restriction unit is configured to limit and, if necessary, suppress the reverse flow of fuel 104 from the outflow port 203 to the coupling point 216. The flow restriction unit 205 may have a check valve configured to completely block reverse flow. Alternatively or additionally, the flow restriction unit 205 (e.g., in parallel with the check valve) may have a throttle valve configured to limit reverse flow to a defined maximum value (e.g., the maximum value of mass flow and / or volume flow).

[0057] Correspondingly, a flow restriction unit 204 may also be arranged on the inflow channel 221 between the inflow port 201 and the coupling point 216. This flow restriction unit limits the reverse flow of fuel 104 from pressure vessels 110, 120 to a defined maximum value (e.g., by means of a throttle valve) and / or blocks the reverse flow (e.g., by means of a check valve). Thus, the fuel flow for pressure balancing can be restricted via inlet lines 111, 121 (e.g., at the start of the refueling process).

[0058] In the event of an operational interruption of the pressure vessel system 100, particularly the energy converter 103, it is generally necessary to ensure that the pressure vessel valves 206 of one or more pressure vessels 110, 120 of the pressure vessel system 100 are reliably closed to prevent accidental leakage of fuel 104 from the one or more pressure vessels 110, 120. For this purpose, the pressure vessel system 100 may accordingly include pressure vessel pressure sensors 115, 125 in the one or more pressure vessels 110, 120, which are configured to detect internal pressure sensor data relating to the internal pressure of the respective pressure vessel 110, 120. Furthermore, the pressure vessel system 100 may accordingly include line pressure sensors 116, 126 in the one or more extraction lines 113, 123, which are configured to detect line sensor data relating to the pressure of fuel 105 in the respective extraction lines 113, 123.

[0059] If necessary, estimates of the internal pressure in pressure vessels 110 and 120 can be determined based on inline sensor data. Specifically, when pressure vessel valve 206 of pressure vessels 110 and 120 is open and there is no mass flow of fuel in extraction lines 113 and 123, it can be inferred that the internal pressure in pressure vessels 110 and 120 corresponds to the pressure in extraction lines 113 and 123. This pressure value can then be used as the internal pressure of pressure vessels 110 and 120 (corrected for possible temperature variations if necessary).

[0060] The control unit 150 of the pressure vessel system 100 can be configured to check whether the pressure vessel valves 206 of the pressure vessels 110 and 120 are leaking based on pipeline sensor data for extraction lines 113 and 123 and / or pressure vessel sensor data for the corresponding pressure vessels 110 and 120. In particular, the presence of a leak can be identified based on the pressure difference between the pipeline pressure in the extraction lines 113 and 123 and the internal pressure in the pressure vessels 110 and 120 (especially based on a time-varying curve of the pressure difference). For example, the leakage of fuel 104 from the pressure vessels 110 and 120 can be identified by the time-varying increase in pipeline pressure in the extraction lines 113 and 123.

[0061] When pressure vessel valve 206 of pressure vessels 110 and 120 is open for an extended period, the pressure in extraction lines 113 and 123 typically rises relatively rapidly due to their relatively small volume. This results in the line pressures in extraction lines 113 and 123 largely corresponding to the internal pressures in pressure vessels 110 and 120, and therefore the sealing performance of pressure vessel valve 206 cannot be determined based on the pressure difference between the line pressures in extraction lines 113 and 123 and the internal pressures in pressure vessels 110 and 120.

[0062] Pressure vessel system 100, particularly energy converter 103, may have one or more operating modes in which only a relatively small volumetric flow of fuel 104 from the one or more pressure vessels 110, 120 is required. This operating mode is also referred to herein as a power-reduced operating mode. An example operating mode with reduced fuel demand is freeze regulation of energy converter 103, in which fuel 104 is blown through energy converter 103 to drive water out of energy converter 103 in preparation for deactivation of energy converter 103.

[0063] During freeze conditioning, the energy converter 103 (especially the fuel cell or fuel cell stack) requires a relatively small amount of fuel 104 (especially H2), but this amount is typically greater than the amount of fuel already supplied in the high-pressure and / or medium-pressure lines 113, 123. Therefore, it is typically required for freeze conditioning to supply fuel 104 to the energy converter 103 from at least one pressure vessel 110, 120. For this purpose, the pressure vessel valve 206 of the one or more pressure vessels 110, 120 may remain open during and / or until freeze conditioning is complete. However, this results in the line pressure in the extraction lines 113, 123 of the pressure vessels 110, 120 corresponding to the internal pressure of the pressure vessels 110, 120 after freeze conditioning has ended, making it unreliable to identify whether the pressure vessel valve 206 is sealed based on sensor data from pressure sensors 115, 125, 116, 126.

[0064] The control unit 150 can be configured to intermittently or pulsedly operate the pressure vessel valves 206 of pressure vessels 110 and 120 to flow fuel 104 from pressure vessels 110 and 120 into extraction lines 113 and 123. Pulsed operation can cause the line pressure in extraction lines 113 and 123 to be lower than the internal pressure in pressure vessels 110 and 120 after the pressure vessel valve 206 is closed. This allows for reliable verification of the sealing of pressure vessel valve 206 based on line sensor data from pressure sensors 116 and 126 on extraction lines 113 and 123.

[0065] Figure 3 An exemplary time-varying curve 300 of the pipeline pressure in extraction lines 113 and 123 is shown. Control unit 150 can be configured to monitor the pipeline pressure based on pipeline sensor data. When the pipeline pressure reaches or falls below a lower pressure limit 301 (e.g., 100 bar), a control pulse or energy pulse 310 can be triggered to actuate pressure vessel valve 206 (specifically, the electromagnet of valve 206), thereby pulse-opening pressure vessel valve 206. The actuation using energy pulse 310 occurs at pulse time points 311 and 312. Figure 3 As exemplarily shown, the energy pulse 310 may have a defined current intensity.

[0066] As a result of the pulsed opening of the pressure vessel valve 206, the line pressure increases (e.g., up to the upper pressure limit 302, e.g., 200 bar). Subsequently, the line pressure decreases again due to fuel consumption by the energy converter 103, and when the lower pressure limit 301 is reached, an energy pulse 310 can be triggered again to direct fuel 104 into the extraction lines 113, 123, and thus increase the line pressure again.

[0067] Pressure vessel valve 206 can therefore operate in a pulsed manner, ensuring that the line pressure in extraction lines 113 and 123 is always between the lower pressure limit 301 and the upper pressure limit 302, where the upper pressure limit 302 is less than the internal pressure in pressure vessels 110 and 120. This allows for regulation of the line pressure in extraction lines 113 and 123, where one or more parameters of the energy pulse 310 (e.g., pulse duration and / or pulse energy) are control parameters of the regulation loop. By adjusting the line pressure to a defined pressure range, it can be ensured that after operation of pressure vessel valve 206 ends, the line pressure is less than the internal pressure of pressure vessels 110 and 120, thereby reliably verifying or monitoring the sealing performance of pressure vessel valve 206.

[0068] As explained above, the volumes of extraction lines 113 and 123 are typically relatively small, so even a relatively short opening pulse of pressure vessel valve 206 can cause a significant increase in line pressure within extraction lines 113 and 123. As a result, it may not be possible (if necessary, solely) to adapt the energy pulse 310 based on line sensor data to limit the line pressure to the upper pressure limit 302. In particular, line pressure regulation is typically not possible (solely) based on line sensor data.

[0069] Figure 4 Exemplary characteristic data 400, particularly characteristic curves, are shown. This characteristic data can be used to adapt the energy pulse 310 used to control the pressure vessel valve 206 to the corresponding conditions in order to cause the pipeline pressure to be limited to the upper pressure limit 302. The characteristic data 400 can be determined in advance in experiments and stored in the storage unit (not shown) of the pressure vessel system 100, particularly the control unit 150.

[0070] The feature data 400 can be shown as a function of the state data 401 regarding the state of the pressure vessel system 100, indicating the parameters 402 of the energy pulse 310 used to control the pressure vessel valve 206, and in particular the parameters 402 regarding the energy of the energy pulse 310.

[0071] Example parameter 402 is as follows:

[0072] The current intensity of energy pulse 310;

[0073] The voltage of energy pulse 310;

[0074] The duration of energy pulse 310;

[0075] The electrical power of the energy pulse 310; and / or

[0076] The accumulated electrical energy of energy pulse 310.

[0077] Example status data 401 is:

[0078] The (current) internal pressure of pressure vessels 110 and 120;

[0079] The temperature of fuel 104 in pressure vessels 110 and 120;

[0080] Extract the (current) line pressure in lines 110 and 120; and / or

[0081] The (current) pressure difference between the internal pressure and the pipeline pressure.

[0082] The characteristic data 400 can be determined as follows: starting from the current state of the pressure vessel system 100, a predetermined pressure increase is caused in the extraction lines 113, 123 by an energy pulse 310 generated according to the determined parameters 402, for example, a pressure increase from the lower pressure limit 301 to the upper pressure limit 302.

[0083] Control unit 150 can be configured to determine state data 401 related to the current state of pressure vessel system 100 at pulse time points 311, 312. Based on the characteristic data 400, parameters 402 for the energy pulse 310 to be generated can then be determined. The energy pulse 310 can then be generated according to the determined parameters 402, for example, to cause pressure vessel valve 206 to open to such an extent and / or for such a duration that the line pressure in extraction lines 113, 123 is increased (as accurately as possible) to the upper pressure limit 302.

[0084] In other words, the pressure vessel valve 206 of pressure vessels 110 and 120 can be operated such that the pressure vessel valve 206 is opened only temporarily or pulsedly. For example, the pressure vessel valve 206 can be energized for a relatively short period of time, such as 20 ms, and then the energization can be interrupted. During the energization interval, the valve seat is briefly opened and the inrush flow of fuel 104 flows into lines 113 and 123. The pressure in the high-pressure lines 113 and 123 increases, but not to the same extent as the internal pressure in pressure vessels 110 and 120.

[0085] With this operating mode, the pressure in high-pressure lines 113 and 123 can be adjusted, and in particular regulated, within a pressure window between a lower pressure limit 301 (e.g., 100 bar) and a higher pressure limit 302 (e.g., 200 bar). This allows for closure checks of pressure vessel valve 206 to be performed at any point in time. Another advantage achieved by reducing the pressure in high-pressure lines 113 and 123 is that less fuel is also present therein, thus reducing the release of fuel 104 into the environment in the event of a failure during a freeze regulation process with subsequent leakage.

[0086] Pulsed operation of pressure vessel valve 206 allows for a relatively low fuel mass flow, as is present during freeze conditioning. However, the measures described herein can generally be used for operating modes of pressure vessel system 100 with a reduced fuel mass flow (relative to normal operation).

[0087] As described above, the inflow into lines 113 and 123 depends on the internal pressure in pressure vessels 110 and 120 and the line pressure in lines 113 and 123. Table 1 exemplarily illustrates the pressure rise in the extraction lines 113 and 123 caused by different opening durations of pressure vessel valve 206 and / or different internal pressures in pressure vessels 110 and 120.

[0088]

[0089] Table 1

[0090] Table 1 shows that, under lower internal pressure and with the same pulse length, the inflow rate of fuel 104 from pressure vessels 110 and 120 is greater. This is because the magnet of pressure vessel valve 206 must overcome the internal pressure of pressure vessels 110 and 120 to open pressure vessel valve 206. Under lower internal pressure, a smaller magnetic force is sufficient to overcome the reaction force caused by the internal pressure. In other words, valve 206 remains open for a longer period of time under an internal pressure of 500 bar than under an internal pressure of 700 bar. Table 1 also shows that, with a pulse duration of 10 ms, valve 206 does not open due to its inertia.

[0091] Based on this measurement, a comprehensive characteristic curve 400 can be created based on the internal pressure of pressure vessels 110, 120 and / or the pipeline pressure of extraction lines 113, 123, to show the pressure rise caused by the energy pulse 310. This comprehensive characteristic curve 400 can be stored in the control device 150 of the pressure vessel system 100 and used to regulate the pipeline pressure, for example, within a range between a lower pressure limit 301 and a higher pressure limit 302.

[0092] To reduce the number of opening cycles of pressure vessel valve 206, pressure vessel valve 206 of the first pressure vessel 110 and pressure vessel valve 206 of the second pressure vessel 120 can be opened alternately in the pressure vessel system 100 having multiple pressure vessels 110, 120. Alternatively, pressure vessel valve 206 of the first pressure vessel 110 and pressure vessel valve 206 of the second pressure vessel 120 can be used alternately during different operating processes (e.g., during different freeze regulation processes).

[0093] The pressure vessel valve 206 can be constructed in multiple stages. In particular, the pressure vessel valve 206 can have a pilot seat (with a relatively small cross-section) and a main seat (with a relatively large cross-section). The pressure vessel valve 206 can be operated (e.g., by using a relatively low current level) such that only the pilot seat, but not the main seat, is opened due to the energy pulse 310. Here, the pressure vessel valve 206 can be constructed such that reduced wear (or no wear at all) is caused by opening only the pilot seat. In particular, the pressure vessel valve 206 can be designed to be durable relative to the pilot seat, so that the number of open / close cycles is unlimited. Therefore, particularly reliable operation of the pressure vessel valve 206 can be achieved. Furthermore, due to the relatively small mass flow through the pressure vessel valve 206 when only the pilot seat is open, the window between the lower pressure limit 301 and the upper pressure limit 302 can be kept relatively small.

[0094] Figure 5 A flowchart is shown of a method 500 (computer-implemented if necessary) for operating pressure vessel valve 206 of pressure vessels 110, 120. Here, pressure vessel valve 206 is configured to direct fuel 104 (especially H2) from pressure vessels 110, 120 into extraction lines 113, 123 for supplying energy converter 103 (especially fuel cell).

[0095] Method 500 includes method step 501: determining the existence of a power-reduced operating mode of energy converter 103. Here, a power-reduced operating mode may exist if the mass flow of fuel supplied to energy converter 103 (at any point in time during the implementation of the power-reduced operating mode, if necessary) is less than or equal to a predetermined mass flow threshold. Pressure vessel system 100 may, for example, be designed for a nominal mass flow (when pressure vessel valve 206 remains permanently open). The mass flow threshold may, for example, be 50% or less of the nominal mass flow, or 30% or less, or 10% or less. An exemplary power-reduced operating mode is freeze regulation of energy converter 103.

[0096] Method 500 further includes method step 502: intermittently (i.e., pulsedly) opening pressure vessel valve 206 during the (entire) implementation of the power-reduced operating mode, so as to correspondingly introduce the inflow of fuel 104 from pressure vessels 110, 120 into extraction lines 113, 123. Here, the intermittent opening of pressure vessel valve 206 can be performed such that the fuel pressure in extraction lines 113, 123 is always lower than the fuel pressure in pressure vessels 110, 120 by at least a predetermined offset value (e.g., 10% or more). Through the intermittent operation of pressure vessel valve 206, a reliable verification of the sealing performance of pressure vessel valve 206 can therefore be achieved during and / or after the end of the power-reduced operating mode (based on the temporal development of fuel pressure in extraction lines 113, 123).

[0097] This invention is not limited to the embodiments shown. In particular, it should be noted that the specification and drawings are intended to illustrate only the principles of the proposed methods, apparatus, and systems.

[0098] List of reference numerals

[0099] 100 Pressure Vessel System

[0100] 101 Fuel Inlet

[0101] 102 Pressure Converter

[0102] 103 Energy Converter

[0103] 104 fuel

[0104] 110, 120 pressure vessels

[0105] Supply lines 111 and 121

[0106] Valve devices 112 and 122

[0107] Extraction pipelines 113 and 123

[0108] 115, 125 Pressure Sensors (Pressure Vessels)

[0109] 116, 126 Pressure sensors (extraction tubing)

[0110] 150 control unit

[0111] 201 Inflow Interface

[0112] 202 Inflow Filter

[0113] 203 Outgoing Interface

[0114] 204, 205 Flow restriction units

[0115] 206 Electrically operated valve

[0116] 207 Manual valve (in parallel with electrically operated valve)

[0117] 208 Evaluation Units

[0118] 209 Pressure Relief Unit

[0119] 210 Data Interface

[0120] 211 Exhaust Unit

[0121] 212 Outflow Filter

[0122] 213 Temperature Sensor

[0123] 214 Manual valve (in series with electrically operated valve)

[0124] 215 Check valve (connected in parallel with electrically operated valve)

[0125] 216 coupling points

[0126] 221 Inflow Channel

[0127] 222 Common Corridor

[0128] 223 Outflow Channel

[0129] Pressure limits 301 and 302

[0130] Pressure change curve over 300 seconds

[0131] 310 Energy Pulse (used to control pressure vessel valves)

[0132] Pulse time points 311 and 312

[0133] 400 feature data (especially feature curves)

[0134] 401 Status Data

[0135] Parameters of 402 energy pulse

[0136] 500 Methods for operating valves in pressure vessels

[0137] Methods and steps for 501 and 502.

Claims

1. A control unit (150) for a pressure vessel system (100), the pressure vessel system comprising at least one pressure vessel (110, 120) having a pressure vessel valve (206) configured to introduce fuel (104) from the pressure vessel (110, 120) into an extraction line (113, 123) for supplying an energy converter (103); wherein, The control unit (150) is configured to, - Determine the existence of an operating mode in which the power of the energy converter (103) is reduced; wherein, in the operating mode in which the power is reduced, the fuel mass flow supplied to the energy converter (103) is less than or equal to a predetermined mass flow threshold; - This causes the pressure vessel valve (206) to open intermittently during the implementation of the power reduction operating mode, so as to correspondingly introduce the inflow of fuel (104) from each of the pressure vessels (110, 120) into the extraction lines (113, 123), thereby... - The pressure in the extraction lines (113, 123) does not exceed a predetermined upper pressure limit (302); wherein the upper pressure limit (302) is less than the internal pressure in the pressure vessels (110, 120); and / or - The pressure in the extraction lines (113, 123) is always at least a predetermined offset value lower than the internal pressure in the pressure vessels (110, 120). - After the power reduction operation mode ends, determine the pipeline sensor data related to the time development of the pressure in the extraction pipeline (113, 123); wherein the pressure vessel valve (206) closes after the power reduction operation mode ends; - Based on the aforementioned pipeline sensor data, identify the temporal increase in pressure within the extraction pipelines (113, 123); and - Based on this, it is determined that the pressure vessel valve (206) is not sealed.

2. The control unit (150) according to claim 1, wherein, The control unit (150) is configured to, - Determine the pressure in the extraction lines (113, 123); and - The pressure vessel valve (206) is opened intermittently according to the pressure in the extraction line.

3. The control unit (150) according to claim 2, wherein, The control unit (150) is configured to, - The pressure in the extraction lines (113, 123) is detected to be at or below the lower pressure limit (301); and - This responsively generates energy pulses (310) to intermittently open the pressure vessel valve (206).

4. The control unit (150) according to any one of claims 1 to 3, wherein, The control unit (150) is configured to, - Determine status data (401) related to the current state of the pressure vessel system (100); and - Causes an energy pulse (310) depending on the state data (401) to intermittently open the pressure vessel valve (206).

5. The control unit (150) according to claim 4, wherein, The status data (401) includes: - Information regarding the current pressure in the extraction lines (113, 123); and / or - Information regarding the current pressure in the pressure vessels (110, 120); and / or - Information regarding the temperature of the fuel (104).

6. The control unit (150) according to claim 4, wherein, - The control unit (150) is configured to adjust one or more parameters (402) of the energy pulse (310) according to the status data (401). as well as - The one or more parameters (402) include: - The current intensity caused by opening the pressure vessel valve (206); - The voltage value caused by opening the pressure vessel valve (206); - The duration of the energy pulse (310); and / or - The electrical power and / or electrical energy of the energy pulse (310).

7. The control unit (150) according to claim 4, wherein, The control unit (150) is configured to generate the energy pulse (310) based on the status data (401), so that - Adjust the pressure in the extraction lines (113, 123) to the predetermined upper pressure limit (302); and / or - A predetermined pressure difference that causes a pressure increase in the extraction lines (113, 123).

8. The control unit (150) according to claim 4, wherein, - The control unit (150) is configured to induce the energy pulse (310) based on predetermined characteristic data (400) for the pressure vessel system (100); and - Feature data (400) indicates parameter values ​​for one or more parameters (402) for the energy pulse (310) for multiple different state data (401).

9. The control unit (150) according to claim 8, wherein, - The feature data (400) has been predetermined in the experiment; and / or - The characteristic data (400) has been determined so that, starting from the current state of the pressure vessel system (100) as shown by the state data (401), the pressure in the extraction lines (113, 123) is increased by a predetermined pressure difference and / or increased to a predetermined pressure upper limit (302).

10. The control unit (150) according to any one of claims 1 to 3, wherein, - The pressure vessel valve (206) has a pilot seat and a main seat; - When the pilot seat of the pressure vessel valve (206) is open, the fuel mass flow from the pressure vessel (110, 120) is less than the fuel mass flow when the main seat of the pressure vessel valve (206) is open; - Opening the pilot seat causes less wear on the pressure vessel valve (206) than opening the main seat; as well as - The control unit (150) is configured to intermittently open the pressure vessel valve (206), such that during the implementation of the power reduction operating mode, - Do not open the main seat, at least temporarily, or never open the main seat; and / or - At least temporarily or only open the pilot seat.

11. The control unit (150) according to any one of claims 1 to 3, wherein, - The pressure vessel system (100) includes a first pressure vessel valve and a second pressure vessel valve; and - The control unit (150) is configured to at least temporarily and intermittently open the first pressure vessel valve and at least temporarily and intermittently open the second pressure vessel valve during a power reduction operation mode of the energy converter (103) and / or during multiple successive power reduction operation modes.

12. The control unit (150) according to any one of claims 1 to 3, wherein, The control unit (150) is configured to, - Determine the existence of a power operation mode; wherein, in the power operation mode, the fuel mass flow supplied to the energy converter (103) is greater than a predetermined mass flow threshold; and - This causes the pressure vessel valve (206) to remain permanently open during the implementation of the power operation mode in order to introduce fuel (104) from the pressure vessels (110, 120) into the extraction lines (113, 123).

13. The control unit (150) according to any one of claims 1 to 3, wherein, - The fuel (104) comprises hydrogen; - The energy converter (103) includes a fuel cell; and - The reduced power operating mode includes the freeze regulation of the fuel cell.

14. The control unit (150) according to any one of claims 1 to 3, wherein, The control unit (150) is configured to, - Determine mass flow information related to the fuel mass flow to the energy converter (103); as well as - During the implementation of the power reduction operation mode, the pressure vessel valve (206) is intermittently opened based on the mass flow information.

15. The control unit (150) according to claim 14, wherein, The control unit (150) is configured to, - During the implementation of the power reduction operation mode, the pressure vessel valve (206) is intermittently opened according to the mass flow information, such that the fuel mass flow from the pressure vessel (110, 120) provided by opening the pressure vessel valve (206) corresponds at least in average time to the fuel mass flow to the energy converter (103).

16. A pressure vessel system (100), the pressure vessel system comprising: - At least one pressure vessel (110, 120) having a pressure vessel valve (206) configured to introduce fuel (104) from the pressure vessel (110, 120) into an extraction line (113, 123) for supplying an energy converter (103); and - The control unit (150) according to any one of claims 1 to 15 is configured to operate the pressure vessel valve (206).

17. A method (500) for operating a pressure vessel valve (206) of a pressure vessel (110, 120); wherein, The pressure vessel valve (206) is configured to introduce fuel (104) from the pressure vessel (110, 120) into an extraction line (113, 123) for supplying the energy converter (103); wherein the method (500) includes: - Determine the existence of an operating mode in which the power of the energy converter (103) is reduced; wherein, in the operating mode of reduced power, the fuel mass flow supplied to the energy converter (103) is less than or equal to a predetermined mass flow threshold; and - This causes the pressure vessel valve (206) to open intermittently during the implementation of the reduced power operating mode, so as to correspondingly introduce the inflow of fuel (104) from the pressure vessels (110, 120) into the extraction lines (113, 123), thereby... - The pressure in the extraction lines (113, 123) does not exceed a predetermined upper pressure limit (302); wherein the upper pressure limit (302) is less than the internal pressure in the pressure vessels (110, 120); and / or - The pressure in the extraction lines (113, 123) is always at least a predetermined offset value lower than the internal pressure in the pressure vessels (110, 120). - After the power reduction operation mode ends, determine the pipeline sensor data related to the time development of the pressure in the extraction pipeline (113, 123); wherein the pressure vessel valve (206) closes after the power reduction operation mode ends; - Based on the aforementioned pipeline sensor data, identify the temporal increase in pressure within the extraction pipelines (113, 123); and - Based on this, it is determined that the pressure vessel valve (206) is not sealed.

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