Method for opening a valve assembly of a fuel tank
By using a system consisting of a pilot valve and other valves, and by alternating control of enhanced voltage and suction voltage, the problem of fuel tank valve assemblies being difficult to open under high pressure differentials is solved, achieving high-efficiency and safe pressure release.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2020-12-23
- Publication Date
- 2026-06-12
AI Technical Summary
Existing fuel tank valve assemblies are difficult to open efficiently under high pressure differentials and pose safety hazards, especially in the event of an accident where they may not be able to release pressure in time, leading to the risk of combustion.
The system, consisting of a pilot valve and at least one other valve, opens the pilot valve by applying an enhanced voltage, and then alternately shuts off and turns on the suction voltage to maintain the open state. The voltage frequency and amplitude are adjusted according to operating conditions to ensure high energy efficiency and safety.
It enables highly efficient opening of fuel tank valve assemblies, reduces costs, and ensures reliable pressure release in the event of high pressure differentials or accidents, thereby improving safety.
Smart Images
Figure CN115210496B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for opening a valve assembly for a fuel storage tank and a system for opening a valve assembly for a fuel storage tank. Background Technology
[0002] Hydrogen-based fuel cells are considered a future mobility solution because they emit only water as exhaust gas and allow for rapid refueling. Fuel cell systems require air and hydrogen for the chemical reaction. Hydrogen is stored in a gaseous state under pressure in one or more tanks. Pressure vessels known from the prior art typically have multiple tank valves for opening and closing the pressure vessel. These valves are usually constructed as solenoid valves and can be opened by applying, for example, an opening voltage of 12 V. Upon opening, the valve must first overcome a large pressure differential during operation, which briefly requires high energy. Although this high opening energy only needs to be provided for a duration of less than one second during the opening phase and for the rest of the time only a significantly smaller holding energy is required to keep the tank valve open, the magnetic circuit of the solenoid valve must also be designed specifically for the conditions during the opening phase. This excessive size of the solenoid valve's magnetic circuit is particularly disadvantageous from both cost and energy perspectives. Furthermore, for safety-related reasons, the magnetic circuit also needs to be designed accordingly to overcome the large pressure differential in the event of combustion in an accident. Although most pressure vessels are equipped with temperature-controlled safety relief valves (so-called TPRDs), these may open late or not at all in cases where the combustion area is located far from the ground, requiring the pressure inside the pressure vessel to be released via a tank valve due to the increased temperature. However, if the magnetic circuit size is insufficient, the increased pressure inside the tank may cause the tank valve to become completely unable to open because the energy required to overcome the pressure difference cannot be applied. Summary of the Invention
[0003] The subject matter of this invention, according to a first aspect, is a method having features according to the invention, and according to a second aspect, it is a system having features according to the invention. Other features and details of the invention are derived from the specification and drawings. Herein, the features and details described in conjunction with the method according to the invention also apply to the features and details described in conjunction with the system according to the invention, and vice versa, so that reference is always made to or can be made to each other regarding the disclosure of the respective inventive aspects.
[0004] The advantages of the method for opening the valve assembly of a fuel storage tank according to the invention are particularly that the operation of the valve assembly for the fuel storage tank according to the invention enables the opening of multiple valves with exceptionally high energy efficiency. Furthermore, the application of the method according to the invention does not require the special manufacture of specific valves, and therefore reduces costs through standardized manufacturing. In addition, the application of the method according to the invention allows for improved safety, in that reliable opening of the storage tank valves can still be achieved even when there is a large pressure difference between the inside and outside of the pressure vessel, for example, due to combustion.
[0005] The method for opening a valve assembly for a fuel tank according to the invention is particularly suitable for use in motor vehicles, such as passenger cars or trucks. Furthermore, its use in other vehicles or transport vehicles, such as forklifts, cranes, ships, or aircraft, is also conceivable. Its use in stationary systems is also possible. The method for opening a valve assembly for a fuel tank according to the invention, the valve assembly comprising a pilot valve and at least one additional valve, is particularly suitable for use in fuel cell-driven vehicles, and includes the steps of: applying an enhanced voltage during the opening phase of the pilot valve to open the pilot valve; turning off the enhanced voltage to end the opening phase of the pilot valve; applying an attraction voltage during the attraction phase of the pilot valve to maintain the open pilot valve; and alternately turning the attraction voltage on and off during a post-control phase to maintain the open pilot valve and to open and maintain the open at least one additional valve, thereby providing an average required holding-open energy for maintaining the open pilot valve and an average required opening energy and / or holding-open energy for the at least one additional valve.
[0006] Within the scope of this invention, "valve assembly" can be understood in particular as a system of interconnected valves. Furthermore, "pilot valve" is preferably understood as the valve to be operated first before all other valves for closing the pressure vessel, which can advantageously be directly connected to the pressure vessel. The other valves can be correspondingly understood as valves to be operated after the pilot valve for closing the pressure vessel. The pilot valve can be sized similarly to one or more other valves, preferably sized and / or configured exactly the same. Furthermore, within the scope of this invention, "average required holding-open energy" can be understood in particular as energy that must be applied evenly over a defined time period so that the pilot valve and / or at least one other valve remain open after opening. Regarding the transition from the suction phase to the post-control phase, it is understood that the suction voltage before the end of the suction phase of the pilot valve and the enhanced voltage before the end of the open state of the other valves can be turned off before the start of the post-control phase and before the suction voltage can be alternately turned off and on. However, it is also conceivable to start the post-control phase directly, since the suction voltage is already turned off and on during the post-control phase. In an optional final method step, specifically, for example, a shut-off voltage may be set to terminate the control phase. This shut-off is preferably achieved by simultaneously closing a pilot valve and at least one additional valve. It is also understood that, in addition to at least one additional valve, multiple additional valves may be provided, which can be at least partially opened sequentially or simultaneously, or remain open, during the post-control phase.
[0007] In terms of the rapid and efficient opening of the pilot valve and the simultaneous, energy-efficient opening of one or more other valves, according to the invention, the boosting voltage can be advantageously configured to be greater than the attracting voltage, wherein the boosting voltage preferably has a value greater than 12 V, particularly preferably greater than 65 V, and especially at least 400 V. Here, the boosting voltage can be advantageously applied to the solenoid valve, for example, such that an opening current of greater than 5 A, preferably greater than 7 A, and especially at least 10 A flows in the coil of the solenoid valve, at least temporarily, thereby ensuring rapid pressure compensation.
[0008] Similarly, in terms of rapidly and efficiently opening the pilot valve and subsequently opening one or more other valves with high energy efficiency, it is advantageous to set the opening phase to last for more than 2 ms, preferably more than 5 ms, and especially more than 10 ms.
[0009] Furthermore, within the range of particularly energy-efficient operations used to open tank valves, it is advisable that the suction voltage is less than the boosting voltage, wherein the suction voltage preferably has a value of 12 V or less.
[0010] Similarly, in the case of particularly energy-efficient operation for opening tank valves, it can be configured to alternately turn the suction voltage off and on during the post-control phase, thereby regulating an average opening current of at least 2 A and / or maintaining the opening current.
[0011] Furthermore, within the scope of a particularly simple and flexible matching method for a valve assembly for opening a fuel tank, it is conceivable that the frequency and / or amplitude of alternatingly switching the suction voltage on and off during the holding-open phase can vary according to operating conditions, particularly according to back pressure and / or temperature. Such variation in the suction voltage is particularly advantageous in embodiments with multiple additional valves.
[0012] The subject matter of this invention also relates to a system for opening a valve assembly of a fuel storage tank for use in a fuel cell-powered vehicle. Here, the system according to the invention includes a pilot valve, at least one additional valve, and a controller for applying an enhanced voltage to open the pilot valve, and for applying an attraction voltage to maintain the pilot valve open and for opening and maintaining the at least one additional valve open. The controller is configured and arranged internally within the system to provide an average required energy to maintain the open position by alternately switching the attraction voltage on and off, for maintaining the pilot valve open and for opening and maintaining the at least one additional valve open. Therefore, the system according to the invention has the same advantages as those already described in detail with respect to the method according to the invention. Within the scope of a particularly compact and comprehensive embodiment, the system may also include at least one fuel storage tank. Here, the fuel storage tank may be configured, in particular, as a hydrogen storage tank or a natural gas storage tank.
[0013] To ensure sufficient safety even in the event of an accident or complete unloading, the present invention may also advantageously provide that the pilot valve and / or at least one additional valve are configured as self-closing valves, preferably as solenoid valves.
[0014] To identify a favorable time point for initiating the opening process of the pilot valve and / or other valves, a detection unit can be specifically configured to detect measured values to determine the appropriate time point for applying the variable voltage. Possible measured values here may include, in particular, the current back pressure or pressure differential and / or the current internal and / or external temperature.
[0015] Specifically, to reliably determine the advantageous timing for initiating the opening process of the pilot valve and / or other valves, a processing unit can be configured to determine the appropriate timing for applying the variable voltage based on measurements detected by the detection unit. The processing unit can, in particular, perform post-processing on the measurements detected by the detection unit, such as averaging and / or weighting, or other types of analytical processing, to ensure reliable determination of the advantageous timing for initiating the opening process. Furthermore, for simple and rapid data communication, the controller, processing unit, and detection unit are preferably interconnected via control lines. Within the scope of easily combinable and flexibly arranged components, the controller, processing unit, and detection unit can also be wirelessly interconnected via WLAN, Bluetooth, or NFC.
[0016] Furthermore, the subject of this invention is also a motor vehicle including the above-described system, and in particular a fuel cell-driven motor vehicle including the above-described system.
[0017] Other advantages, features, and details of the invention will become apparent from the following description, in which embodiments of the invention are described in detail with reference to the accompanying drawings. Here, the features mentioned in the specification may be important to the invention individually or in any combination. Attached Figure Description
[0018] The attached diagram shows:
[0019] Figure 1 A schematic diagram of the steps of a method for opening a valve assembly for a fuel storage tank according to the present invention.
[0020] Figure 2 A schematic diagram of the control curve of the pilot valve.
[0021] Figure 3 A schematic diagram of the control curve for another tank valve. Detailed Implementation
[0022] Figure 1 A schematic diagram of the steps of a method for opening a valve assembly for a fuel tank according to the present invention is shown, the valve assembly including a pilot valve V1 and at least one additional valve V2, particularly for use in fuel cell driven vehicles.
[0023] Here, the method includes the step of applying an enhancement voltage S1 of 30 V to open the pilot valve V1 during the opening phase P1. Advantageously, the enhancement voltage S1 is greater in magnitude than the subsequent attraction voltage S2, wherein the enhancement voltage S1 preferably has a value greater than 12 V, particularly preferably greater than 65 V, and especially at least 400 V.
[0024] In the subsequent second step of the method according to the invention, the enhanced voltage S1 is turned off to end the opening phase B1 of the pilot valve V1. The opening phase B1 may, for example, last for more than 2 ms, preferably more than 5 ms, and especially more than 10 ms.
[0025] In the subsequent third step of the method according to the invention, an attraction voltage S2 for maintaining the pilot valve V1 open is applied during the attraction phase B2 of the pilot valve V1. The attraction voltage S2 is advantageously less than the boosting voltage S1, wherein the attraction voltage S2 preferably has a value of 12 V or less.
[0026] According to the fourth step of the method according to the invention, immediately following the post-control phase P3, the 36-pulling voltage S2 is alternately switched off and on to maintain the pilot valve V1 open and to open and maintain the opening of the at least one additional valve V2, thereby providing the average required holding-open energy for maintaining the pilot valve V1 open and the average required opening energy and / or holding-open energy for the at least one additional valve V2. Preferably, the pulling voltage S2 is alternately switched off and on in the post-control phase P3, such that an average opening and / or holding-open current of at least 2 A is set. The frequency and / or amplitude of the alternating switching off and on of the pulling voltage S2 in the holding-open phase P3 can be varied, in particular, according to operating conditions, such as back pressure or temperature or similar conditions.
[0027] Figure 2 A schematic diagram of the control curve of pilot valve V1 is shown.
[0028] Pilot valve V1 is initially supplied with an enhanced voltage S1 of 65 V during the opening phase P1, causing the current I to briefly rise to over 10 A. The opening phase P1 of the pilot valve lasts for approximately 10 ms before the 65 V enhanced voltage S1 is turned off and only about 12 V is still applied during the suction phase P2. After the suction phase P2, the 12 V suction voltage S2 is alternately turned off and on during the initial post-control phase P3, thus continuing to provide the average required holding-open energy for pilot valve V1.
[0029] Figure 3 The control curve for the additional tank valve V2 is shown. After the pilot valve V1 opens, it is responsible for increasing the pressure in the high-pressure circuit, thereby overcoming the compensating pressure and opening the additional tank valve V2 with significantly less energy. For this purpose, a boosting voltage of, for example, 65 V V1 is not required; a 12 V suction voltage S2 is sufficient. By alternately switching the current 12 V suction voltage S2 on and off, the additional valve V2 is supplied with an average current of approximately 2 A, which is responsible for reliably opening and maintaining the valve open.
[0030] This post-control phase P3 continues until valve V2 and pilot valve V1 close again at the end of the trip. This is achieved by adjusting the 12V power supply. Furthermore, depending on operating conditions, particularly back pressure and / or temperature, the frequency, phase, and amplitude of the voltage supply with the attracting voltage S2 shown can be varied. In emergency opening situations overcoming particularly high pressures (e.g., during or shortly after an accident accompanied by combustion and thus a rise in pressure within the tank), the enhanced voltage S1 on pilot valve V1 can be applied significantly longer and more frequently to ensure opening and maintain the open position.
Claims
1. A method for opening a valve assembly for a fuel tank, the valve assembly comprising a pilot valve (V1) and at least one additional valve (V2), the method for use in a fuel cell-driven vehicle, the method comprising the steps of: An enhanced voltage (S1) is applied during the opening phase (P1) of the pilot valve (V1) to open the pilot valve (V1). When the opening phase (P1) of the pilot valve (V1) ends and the suction phase (P2) begins, the enhancement voltage (S1) is switched to the suction voltage (S2). The suction voltage (S2) is applied during the suction phase (P2) of the pilot valve (V1) to keep the pilot valve (V1) open, wherein the suction voltage (S2) is different from the boosting voltage (S1). In the post-control phase (P3), the suction voltage (S2) is alternately turned on and off to maintain the pilot valve (V1) open and to open and maintain the opening of the at least one additional valve (V2), thereby providing the average required holding-open energy for maintaining the pilot valve (V1) open and the average required opening energy and / or holding-open energy for the at least one additional valve (V2).
2. The method according to claim 1, Its features are, The enhanced voltage (S1) is greater than the attracting voltage (S2) in magnitude.
3. The method according to claim 1 or 2, Its features are, The opening phase (P1) lasts for more than 2 ms.
4. The method according to claim 1 or 2, Its features are, The attraction voltage (S2) is less than the enhancement voltage (S1).
5. The method according to claim 1 or 2, Its features are, In the post-control phase (P3), the attracting voltage is alternately turned off and on (S2) to set an average on-state current of at least 2 amperes and / or maintain the on-state current.
6. The method according to claim 1 or 2, Its features are, The frequency and / or amplitude of the attraction voltage (S2) being alternately switched on and off during the post-control phase (P3) varies depending on the operating conditions.
7. The method according to claim 2, Its features are, The enhanced voltage (S1) has a value greater than 12 V.
8. The method according to claim 2, Its features are, The enhanced voltage (S1) has a value greater than 65 V.
9. The method according to claim 2, Its features are, The enhanced voltage (S1) has a value of at least 400 V.
10. The method according to claim 3, Its features are, The opening phase (P1) lasts for more than 5 ms.
11. The method according to claim 3, Its features are, The opening phase (P1) lasts for more than 10 ms.
12. The method according to claim 4, Its features are, The attraction voltage (S2) has a value of less than or equal to 12 V.
13. The method according to claim 6, Its features are, In the post-control phase (P3), the frequency and / or amplitude of the attraction voltage (S2) being alternately switched on and off varies according to the reverse pressure and / or temperature.
14. A system (1) for opening a valve assembly of a fuel tank for use in a fuel cell-driven vehicle, said system for implementing the method according to any one of claims 1 to 13, said system comprising: Pilot valve (V1); At least one additional valve (V2); A controller is configured to apply an enhanced voltage (S1) to open the pilot valve (V1), and to apply an attraction voltage (S2) to maintain the pilot valve (V1) open and to open and maintain the opening of the at least one additional valve (V2). The controller is configured and arranged within the system (1) to provide an average required holding-open energy by alternately turning the attracting voltage (S2) on and off, for holding the pilot valve (V1) open and for opening and holding the at least one other valve (V2) open.
15. The system (1) according to claim 14, Its features are, The pilot valve (V1) and / or the at least one additional valve (V2) are in the form of a self-closing valve.
16. The system according to claim 14 or 15, Its features are, A detection unit is set up to detect the measured value and to determine the appropriate time point for applying the variable voltage.
17. The system according to claim 16, Its features are, A processing unit is configured to determine the appropriate time to apply the variable voltage based on the measurement values detected by the detection unit.
18. The system (1) according to claim 15, Its features are, The pilot valve (V1) and / or the at least one additional valve (V2) are configured as solenoid valves.
19. A motor vehicle comprising the system according to any one of claims 14 to 18.
20. The motor vehicle according to claim 19, Its features are, The motor vehicle in question is a vehicle powered by a fuel cell.