System and method for generating vibrations on at least one component of a fuel cell system as well as fuel cell system

Abstract

System (30) for generating vibrations on at least one component of a fuel cell system (1), comprising at least one vibration device (34) that can be arranged on the fuel cell system (1) or is at least partially formed by at least one component of the fuel cell system (1) for generating excitation vibrations that can be transmitted to the component, and at least one control electronics (31) for controlling the vibration device (34), wherein the control electronics (31) are configured to control the vibration device (34) during a switch-on process and / or a switch-off process of the fuel cell system (1) taking into account at least one natural frequency of the component stored in the control electronics (31), and wherein the vibration device is at least partially controlled by at least one valve (8, 9, 13, 16, 20,29) of a cathode gas system (10) or a hydrogen system (5) or a cooling system (23) of the fuel cell system (1, 32), wherein the control electronics (31) are configured to switch the valve (8, 9, 13, 16, 20, 29) back and forth at a predetermined frequency during the switch-on and / or switch-off process between an open state in which the valve (8, 9, 13, 16, 20, 29) is partially or fully open and a closed state different from the open state in which the valve (8, 9, 13, 16, 20, 29) is less open than in the open state,

Description

[0001] The invention relates to a system for generating vibrations in at least one component of a fuel cell system, comprising at least one vibration device that can be arranged on the fuel cell system or is at least partially formed by at least one component of the fuel cell system for generating excitation vibrations that can be transmitted to the component, and at least one control electronics system for controlling the vibration device. Furthermore, the invention relates to a fuel cell system. Furthermore, the invention relates to a method for generating vibrations in at least one component of a fuel cell system.

[0002] To start and operate a fuel cell system at temperatures below 0°C, fuel cell channels and fuel cell connections, in particular, must be free of ice blockages. Such ice blockages can, at best, lead to an interruption of the start-up process due to a hydrogen and / or oxygen deficiency, and, at worst, to damage to some or all of the fuel cells in the fuel cell system. Various measures have been proposed to prevent the formation of such ice blockages or to remove them.

[0003] US 2013 / 0 095 406 A1 discloses a method and system for improving the efficiency of fuel cells by removing obstructions within a fuel cell channel. The system includes at least one sensor and a processor for determining when a concentration level of a gas, such as carbon dioxide, has exceeded a maximum threshold. The processor then activates an obstruction removal element to remove or release gas bubbles within the fuel cell channel that are blocking reaction sites or fuel flow.

[0004] US 2016 / 0 380 286 A1 discloses a fuel cell system comprising a compressor placed in a supply flow path arranged to supply a cathode gas to a fuel cell, a first motor-driven valve placed between the fuel cell and the compressor in the supply flow path, a first stepping motor formed in the first motor-driven valve, a second motor-driven valve placed in an outlet flow path arranged to discharge the cathode gas from the fuel cell, a second stepping motor formed in the second motor-driven valve, and a controller configured to control power generation of the fuel cell and input drive pulses to the first stepping motor and the second stepping motor.so as to open the first motor-driven valve and the second motor-driven valve when the fuel cell starts up, and to close the first motor-driven valve and the second motor-driven valve when the fuel cell stops. The first stepper motor is driven by the input of the drive pulses to generate a torque to open and close the first motor-driven valve. The second stepper motor is driven by the input of the drive pulses to generate a torque to open and close the second motor-driven valve. The controller determines whether at least one of the first motor-driven valve and the second motor-driven valve is in a frozen state when the fuel cell starts up. If it is determined that neither the first motor-driven valve nor the second motor-driven valve is in the frozen state,The controller starts power generation by the fuel cell. If it is determined that at least one of the first motor-driven valve and the second motor-driven valve is in the frozen state, the controller performs a predefined process that alternately repeats, for a plurality of times, inputting a first drive pulse that generates a torque in a direction of increasing a valve opening and a second drive pulse that has a higher pulse speed than a pulse speed of the first drive pulse and generates a torque in a direction of decreasing the valve opening to a stepping motor formed in at least the motor-driven valve in the frozen state from the first stepping motor and the second stepping motor.

[0005] US 6 855 444 B2 discloses a fuel cell system comprising a fuel cell that generates electrical energy through a chemical reaction between hydrogen and oxygen.The fuel cell system includes outside air temperature detecting means for detecting the outside air temperature in the vicinity of the fuel cell, outside air temperature estimating means for estimating, after deactivation of the fuel cell, a drop in the outside air temperature due to a change in the outside air temperature detected by the outside air temperature detecting means, icing deciding means for deciding whether or not the estimated outside air temperature obtained by the outside air temperature estimating means is below a predetermined icing temperature at which moisture freezes, and anti-icing executing means for preventing moisture inside the fuel cell from freezing when the icing deciding means has decided that the outside air temperature is below the predetermined icing temperature.

[0006] US 2005 / 0 238 934 A1 discloses a fuel cell unit with a fuel cell stack consisting of a plurality of fuel cells that generate electrical energy through a reaction of hydrogen and oxygen. A controller determines whether moisture within the fuel cell stack is frozen or not. If the moisture is frozen, the controller causes the fuel cell stack to generate intermittent electrical energy via an inverter while continuing to supply oxygen to the fuel cell stack. The fuel cell stack generates heat as a result of generating electrical energy, thereby generating moisture in a cathode.During periods when no electrical energy generation is taking place, the oxygen supplied to the cathode of the fuel cells flushes out the moisture produced, thus ensuring the supply of oxygen to the cathode during electrical energy generation.

[0007] US 2008 / 0 241 608 A1 discloses a method for operating a fuel cell stack, wherein the fuel cell stack having a temperature below 0°C is started and a load is applied to the fuel cell ranging from 75 percent of the maximum to the maximum load to which the fuel cell stack is capable of responding, the maximum load being limited by the fuel cell system constraints and the applied load being greater than that requested by the operator to operate primary and auxiliary power devices. The application of the load is continued at an amount greater than that requested by the operator, at least until the temperature of the fuel cell stack is above 0°C.

[0008] US 9 428 077 B2 discloses a vehicle with a fuel cell system having a fuel cell stack for generating power and a controller configured to receive a first signal indicative of a predicted outside temperature at a specified location and command the fuel cell system to operate at a reduced relative humidity in the fuel cell stack when the predicted outside temperature is below a threshold.

[0009] The publication available under the link https: / / gow.epsrc.ukri.org / NGBOViewGrant.aspx?GrantRef=EP / M005321 / 1 (UNIVERSITY OF SOUTHAMPTON: Aircraft de-icing using high frequency vibration - details of grant. 29 September 2014 - 28 January 2015. Swindon : Engineering and Physical Sciences Research Council - EPRSC,

[2015] (EP / M005321 / 1)) discloses a method for de-icing the wings of an aircraft using vibrations.

[0010] DE 10 2018 209 450A1 relates to a method for determining the stack moisture content of a fuel cell stack of a fuel cell system comprising a plurality of fuel cells and mechanically coupled to a blower, comprising the steps: - Imposing a mechanical vibration on the fuel cell stack, - measuring a measuring vibration frequency or a measuring vibration spectrum of the fuel cell stack by means of at least one sensor, - comparing the measuring vibration frequency or the measuring vibration spectrum in a comparator with a target vibration frequency or a target vibration spectrum that can be stored or is stored in a memory and - Discharging or removing liquid from the fuel cell stack when a deviation of the measuring vibration frequency or the measuring vibration spectrum from the target vibration frequency or the target vibration spectrum is detected, wherein the vibration is impressed on the fuel cell stack by means of the fan.

[0011] JP 2003-123814 A also addresses the provision of a fuel cell that can easily detect water clogging. In a fuel cell system comprising a fuel cell stack and a control device that controls the operating state of the fuel cell stack, the control device detects the resonant frequency of the fuel cell stack and compares the frequency with a standard value to determine whether the fuel cell stack is clogged by water.

[0012] DE 10 2009 006 128 A1 and DE 10 2009 006 129 A1 each disclose a system for generating vibrations in a fuel cell of a fuel cell system. The respective system comprises a vibration device arranged on the fuel cell for generating excitation vibrations that can be transmitted to the fuel cell.

[0013] The invention is based on the object of improving the operation, in particular the starting operation, of a fuel cell system at temperatures below 0°C.

[0014] According to the invention, the object is achieved by a system having the features of claim 1.

[0015] A system for generating vibrations on at least one component of a fuel cell system is shown, comprising at least one vibration device that can be arranged on the fuel cell system or is at least partially formed by at least one component of the fuel cell system for generating excitation vibrations that can be transmitted to the component, and at least one control electronics for controlling the vibration device, wherein the control electronics are configured to control the vibration device during a switch-on process and / or a switch-off process of the fuel cell system, taking into account at least one natural frequency of the component stored in the control electronics, and wherein the vibration device is at least partially formed by at least one valve of a cathode gas system or a hydrogen system or a cooling system of the fuel cell system, wherein the control electronics are configuredto switch the valve back and forth during the switch-on process and / or the switch-off process with a predetermined frequency between an opening state in which the valve is partially or fully open and a closing state deviating from the opening state in which the valve is less open than in the opening state.

[0016] Advantageous embodiments of the invention are disclosed in the subclaims.

[0017] It should be noted that the features and measures listed individually in the following description can be combined with one another in any technically reasonable manner and demonstrate further embodiments of the invention. The description further characterizes and specifies the invention, particularly in conjunction with the figures.

[0018] The vibration device can be used to generate vibrations on the component of the fuel cell system, for example, on a fuel cell stack of the fuel cell system, during the switch-on process, i.e., during an operation start-up process, taking into account at least one natural frequency of the component. This allows any ice deposits on the component to be reliably and quickly removed from the component in order to subsequently ensure normal operation of the fuel cell system. For this purpose, the control electronics can control or activate the vibration device, for example, within a time interval of a predetermined length immediately following the start of operation, to generate excitation vibrations that are transmitted directly or indirectly to the component of the fuel cell system to be defrosted.The length of the time interval can depend on an ambient temperature and / or a system temperature. The length of the time interval is preferably selected such that the excitation oscillations are generated until the fuel cell system is capable of delivering electrical power. The length of the time interval can be between 10 s and 300 s. The at least one natural frequency of the component to be defrosted can be determined in advance and stored in the control electronics.

[0019] Alternatively or additionally, the vibration device can be used to generate vibrations on the component of the fuel cell system during the switch-off process, i.e. during an operation termination process, taking into account at least one natural frequency of the component. This can reliably prevent condensation from remaining on the component when the fuel cell system is switched off, for example in a passage, a channel, a supply connection and / or discharge connection for water, air or hydrogen, and possibly forming droplets that can form ice deposits on the component when the fuel cell system is switched off. For this purpose, the control electronics can control or activate the vibration device, for example within a time interval of a predetermined length immediately prior to the end of operation, to generate excitation vibrations.activate, which are transmitted directly or indirectly to the component of the fuel cell system to be defrosted. The length of the time interval can depend on the ambient temperature, ambient humidity, system temperature, system humidity (e.g., fuel cell stack humidity), and / or system operating time. The length of the time interval can be between 10 s and 120 s. This allows the fuel cell system to be optimally prepared for the next switch-on process, so that, in the best case scenario, no defrosting of the component of the fuel cell system is necessary. At least one natural frequency of the component of the fuel cell system can be determined in advance and stored in the control electronics.

[0020] The system or its vibration device can also be configured to generate vibrations in two or more, in particular all, components of the fuel cell system. The vibration device can have at least one vibration unit manufactured separately from the fuel cell system and arranged or arranged on the fuel cell system. Alternatively, the vibration device can be formed partially or completely by at least one component of the fuel cell system. The excitation vibrations that can be generated with the vibration device are generated taking into account the at least one natural frequency of the component of the fuel cell system, with the control electronics controlling the vibration device accordingly. In this case, the control electronics can be designed as a separate unit or, for example, implemented by vehicle electronics of a vehicle.

[0021] In another embodiment, the vibration device that can be arranged on the fuel cell system has at least one electrically controllable actuator, which is arranged at least indirectly on a housing of the fuel cell system that accommodates at least one fuel cell, or on a component of a support structure of the fuel cell system that does not form a housing, or on an individual fuel cell of the fuel cell system. According to this embodiment, the vibration device is arranged as a separate component on the fuel cell system. The vibration device can also have two or more electrically controllable actuators arranged at different locations on the fuel cell system, which actuators can be controlled by the control electronics.The component of the support structure can, for example, be an end plate resting against a fuel cell stack of the fuel cell system, a tensioning band that braces the cells of the fuel cell stack against each other, or the like. The actuator can, for example, comprise at least one piezo element or be designed as an electric motor.

[0022] Another embodiment provides for the actuator to have a shaft or be shaftless, or at least have a piezoelectric motor. For example, an actuator with a shaft and a shaftless actuator can generate vibrations with a low or medium frequency. A piezoelectric motor can generate vibrations with a high frequency.

[0023] According to another embodiment, the vibration device is configured to generate sound waves or ultrasonic waves. For this purpose, the vibration device can, for example, comprise at least one piezo motor, in particular a piezo excimer.

[0024] As already mentioned above, the vibration device is formed at least partially by at least one valve of a cathode gas system or a hydrogen system or a cooling system of the fuel cell system, wherein the control electronics are configured to switch the valve back and forth during the switch-on process and / or the switch-off process at a predetermined frequency between an open state, in which the valve is partially or fully open, and a closed state, which differs from the open state and in which the valve is less open than in the open state. By switching the respective valve back and forth, the valve generates excitation vibrations, which can be transmitted, in particular mechanically, to the component of the fuel cell system; the component can also be the valve itself.Two valves, in particular throttle valves, of the cathode gas system, with which a cathode gas, in particular air or oxygen, can be supplied to the fuel cells of the fuel cell system, can also be switched accordingly. The valve of the hydrogen system, with which the fuel cells of the fuel cell system can be supplied with hydrogen, can be designed, for example, as a low-pressure valve on a hydrogen supply line of the hydrogen system that supplies hydrogen to the fuel cells, or as a drain valve on a hydrogen discharge line of the hydrogen system that discharges hydrogen from the fuel cells. The valve of the cooling system, with which the fuel cells of the fuel cell system can be cooled during operation, can be arranged, for example, in a supply line of the cooling system that opens into the fuel cell stack. The switching of the respective valve can be effected, for example, via PWM control of the valve.

[0025] A further advantageous embodiment provides that the control electronics can be connected or are connected to an air compressor of the cathode gas system and / or to a pump of the cooling system of the fuel cell system, wherein the control electronics are configured to operate the air compressor and / or the pump at a predetermined speed during the switch-on and / or switch-off process. By means of the air compressor of the cathode gas system, air can be guided through the fuel cell stack of the fuel cell system during the switch-on and / or switch-off process in order to remove a certain amount of moisture from the fuel cell stack, which in particular prevents the formation of ice blockages from condensation on the component of the fuel cell system. In addition, the air compressor can be operated at a speed at which a natural oscillation of the component of the fuel cell system is excited.The pump of the cooling system can, for example, be operated during the switch-on and / or switch-off process at a speed that excites a natural oscillation of the component of the fuel cell system.

[0026] The above object is further achieved by a fuel cell system having the features of claim 7, which has at least one system according to one of the aforementioned embodiments or a combination of at least two of these embodiments with one another.

[0027] The fuel cell system offers the advantages mentioned above with regard to the system. The system can be used, for example, in a vehicle, such as a land vehicle, in particular a passenger car, in a watercraft, or in an aircraft. Alternatively, the system can be used in a stationary application. The fuel cell system can, for example, generate electrical energy that can be fed to an electrical energy storage device of a vehicle, which can be used, for example, to supply the vehicle's electric drive motors.

[0028] The above object is further achieved by a method having the features of claim 8, according to which the vibrations are generated during a switch-on process and / or a switch-off process of the fuel cell system taking into account at least one natural frequency of the component stored in the control electronics, wherein a valve of a cathode gas system or a hydrogen system or a cooling system of the fuel cell system is switched back and forth at a predetermined frequency during the switch-on process and / or the switch-off process between an open state in which the valve is partially or completely open and a closed state deviating from the open state in which the valve is less open than in the open state.

[0029] The method provides the advantages mentioned above with respect to the system. In particular, the system can be used according to one of the above-mentioned embodiments or a combination of at least two of these embodiments to carry out the method.

[0030] A further advantageous embodiment provides that an air compressor of the cathode gas system and / or a pump of the cooling system of the fuel cell system are operated at a predetermined speed during the startup and / or shutdown processes. This embodiment provides the advantages mentioned above with reference to the corresponding system design.

[0031] Further advantageous embodiments of the invention are disclosed in the dependent claims and the following description of the figures. Fig. 1 a block diagram of an embodiment of a fuel cell system according to the invention and Fig. 2 a schematic representation of a further embodiment of a fuel cell system according to the invention.

[0032] In the different figures, identical parts are always provided with the same reference symbols, which is why they are usually only described once.

[0033] Fig. 1 shows a block diagram of an embodiment of a fuel cell system 1 according to the invention.

[0034] The fuel cell system 1 has a fuel cell stack 2 with several fuel cells (not shown), a stacked anode 3 and a stacked cathode 4.

[0035] Furthermore, the fuel cell system 1 has a hydrogen system 5 with a hydrogen supply line 6 for supplying hydrogen to the stacked anode 3 and a hydrogen discharge line 7 for discharging hydrogen from the stacked anode 3. An electrically controllable valve 8 of the hydrogen system 5 is arranged on the hydrogen supply line 6, and an electrically controllable valve 9 of the hydrogen system 5 is arranged on the hydrogen discharge line 7.

[0036] In addition, the fuel cell system 1 has a cathode gas system 10, with which the stacked cathode 4 can be supplied with air or the oxygen contained therein. The cathode gas system 10 has an air inlet (not shown) through which air is drawn in and fed to an air filter 11 of the cathode gas system 10. The air filtered by the air filter 11 is then fed to an air compressor 12 of the cathode gas system 10, which compresses the air. A controllable shut-off valve 13 is connected downstream of the air compressor 12. When the shut-off valve 13 is open, the compressed air can be fed directly to the stacked cathode 4 via an air supply line 14.

[0037] A humidification bypass line 15 branches off from the air supply line 14, on which a controllable shut-off valve 16 is arranged. When the shut-off valve 16 is open, the compressed air is fed to a humidification unit 17 for humidifying the compressed air, whereby the compressed air humidified by the humidification unit 17 is fed to the stacked cathode 4. By actuating the shut-off valve 16, the humidity supplied to the stacked cathode 4 can be adjusted. The air flowing out of the stacked cathode 4 is fed to the humidification unit 17 and discharged from there via an air discharge line 18.

[0038] Furthermore, an air bypass line 19 branches off from the air supply line 14, on which a controllable shut-off valve 20 is arranged and which is connected to the air discharge line 18. By actuating the shut-off valve 20, the air volume flow supplied to the stacked cathode 4 can be adjusted.

[0039] The air discharge line 18 feeds the air coming from the stacked cathode 4 to a turbine 21, from where the air, after performing work in the turbine 21, is discharged via an air outlet line 22. The turbine 21 is mechanically and drivingly connected to the air compressor 12, so that the air compressor 12 can be driven by the turbine 21. The hydrogen discharge line 7 opens into the air outlet line 22.

[0040] The fuel cell system 1 further comprises a cooling system 23 for cooling the fuel cell stack 2. The cooling system 23 comprises a coolant supply line 24, which is connected on the supply side to a cooler (not shown) and on which a pump 25 is arranged. The coolant supply line 24 supplies a coolant, for example a water mixture, to the fuel cell stack 2. After passing through the fuel cell stack 2, the coolant is discharged from the fuel cell stack 2 via a coolant discharge line 26. The humidification unit 17 is connected on the inlet side via a supply line 27 to the coolant supply line 24 and via a discharge line 28 to the coolant discharge line 26 in order to humidify the air supplied to the humidification unit 17 with the coolant.A switching valve 29 is arranged on the coolant outlet 26, so that the coolant coming from the fuel cell stack 2 is supplied via the controllable switching valve 29 either to the cooler or to the coolant supply line 24.

[0041] Furthermore, the fuel cell system 1 comprises a system 30 for generating vibrations on at least one component, shown or not shown, of the fuel cell system 1. The system 30 comprises a vibration device formed by a component, shown or not shown, of the fuel cell system 1 for generating excitation vibrations that can be transmitted to the component. The component can, for example, be any Fig. 1 shown component of the fuel cell system 1.

[0042] Alternatively or additionally, the system 30, which is not encompassed by the scope of protection of the invention, can have at least one vibration device (not shown) that can be arranged on the fuel cell system 1 and can have at least one electrically controllable actuator (not shown) that can be arranged at least indirectly on a housing (not shown) of the fuel cell system 1 that accommodates at least two fuel cells (not shown) or on a component (not shown) of a support structure (not shown) of the fuel cell system 1 that does not form a housing, or on an individual fuel cell (not shown) of the fuel cell system 1. The actuator can have a shaft or be shaftless or have at least one piezomotor (not shown). The vibration device can be configured to generate sound waves or ultrasonic waves.

[0043] In the embodiment shown, the vibration device can be formed at least partially by the valve 13, 16 and / or 20 of the cathode gas system 10 and / or by the valve 8 and / or 9 of the hydrogen system 5 and / or by the valve 29 of the cooling system 23 of the fuel cell system 1.

[0044] The system 30 has control electronics 31 for controlling the vibration device. The control electronics 31 are configured to control the vibration device during a switch-on and / or switch-off process of the fuel cell system 1, taking into account at least one natural frequency of the component. In particular, the control electronics 31 are configured to switch the valve 8, 9, 13, 16, 20, and / or 29 back and forth at a predetermined frequency during the switch-on and / or switch-off process between an open state, in which the valve 8, 9, 13, 16, 20, and / or 29 is partially or fully open, and a closed state deviating from the open state, in which the valve 8, 9, 13, 16, 20, and / or 29 is less open than in the open state.

[0045] In addition, the control electronics 31 can be connected or can be connected to the air compressor 12 of the cathode gas system 10 and / or to the pump 25 of the cooling system 23 of the fuel cell system 1, wherein the control electronics 31 can be configured to operate the air compressor 12 and / or the pump 25 at a predetermined speed during the switch-on process and / or the switch-off process, wherein the predetermined speed corresponds to the determined natural frequency.

[0046] Fig. Figure 2 shows a schematic representation of a fuel cell system 32. It shows a fuel cell stack housing 33 in which several fuel cells (not shown) are arranged. Four vibration devices 34, not according to the invention, in the form of shaftless actuators, are arranged on the fuel cell stack housing 33. These vibration devices can be controlled by the control electronics 31 to generate vibrations at least in the fuel cell housing 33.

[0047] Furthermore, the fuel cell system 32 can be designed according to the Fig. 1 shown embodiment, which is why to avoid repetition the above description should be Fig. 1 is referred to. List of reference symbols: 1 fuel cell system 2 fuel cell stacks 3 stacked anode 4 stacked cathode 5 Hydrogen system 6 Hydrogen supply line 7 Hydrogen discharge 8 valve on 6 9 Valve on 7 10 Cathode gas system 11 Air filter 12 air compressors 13 Valve on 14 14 Air supply line 15 Humidification bypass line 16 valve on 15 17 Humidification unit 18 Air discharge 19 Air bypass line 20 valve on 19 21 turbines 22 Air outlet duct 23 Cooling system 24 Coolant supply line 25 Pump 26 Coolant drainage 27 supply line 28 Derivation 29 Valve 30 systems 31 Control electronics 32 fuel cell system 33 fuel cell housings 34 Vibration device

Claims

[1] System (30) for generating vibrations on at least one component of a fuel cell system (1), comprising at least one vibration device (34) which can be arranged on the fuel cell system (1) or is at least partially formed by at least one component of the fuel cell system (1) for generating excitation vibrations which can be transmitted to the component, and at least one control electronics (31) for controlling the vibration device (34), wherein the control electronics (31) is designed to control the vibration device (34) during a switch-on process and / or a switch-off process of the fuel cell system (1) taking into account at least one natural frequency of the component stored in the control electronics (31), and wherein the vibration device is at least partially controlled by at least one valve (8, 9, 13, 16, 20,29) of a cathode gas system (10) or a hydrogen system (5) or a cooling system (23) of the fuel cell system (1, 32), wherein the control electronics (31) are configured to switch the valve (8, 9, 13, 16, 20, 29) back and forth during the switch-on process and / or the switch-off process at a predetermined frequency between an opening state in which the valve (8, 9, 13, 16, 20, 29) is partially or completely open, and a closing state deviating from the opening state, in which the valve (8, 9, 13, 16, 20, 29) is less open than in the opening state, [2] System (30) according to claim 1, characterized bythat the control electronics (31) controls or activates the vibration device (34) within a time interval of predetermined length immediately following the start of operation in order to generate excitation vibrations, taking into account at least one natural frequency of the component stored in the control electronics (31). [3] System (30) according to claim 2, characterized by that the length of the time interval depends on an ambient temperature and a system temperature. [4] System (30) according to one of the preceding claims, characterized by that the control electronics (31) controls or activates the vibration device (34) within a time interval of predetermined length immediately preceding the end of operation in order to generate excitation vibrations, taking into account at least one natural frequency of the component stored in the control electronics (31). [5] System (30) according to claim 4, characterized by that the length of the time interval depends on an ambient temperature, ambient humidity, system temperature, system humidity, i.e. fuel cell stack humidity, and / or system operating time. [6] System (30) according to one of the preceding claims, characterized by that the control electronics (31) can be connected or is connected to an air compressor (12) of the cathode gas system (10) and / or to a pump (25) of the cooling system (23) of the fuel cell system (1), wherein the control electronics (31) is designed to operate the air compressor (12) and / or the pump (25) at a predetermined speed during the switch-on process and / or the switch-off process. [7] Fuel cell system (1), characterized by at least one system (30) according to one of the preceding claims. [8] Method for generating vibrations on at least one component of a fuel cell system (1), wherein the vibrations are generated during a switch-on process and / or a switch-off process of the fuel cell system (1) taking into account at least one natural frequency of the component stored in a control electronics (31) of the fuel cell system (1), and wherein a valve (8, 9, 13, 16, 20, 29) of a cathode gas system (10) or a hydrogen system (5) or a cooling system (23) of the fuel cell system (1, 32) during the switch-on process and / or the switch-off process at a predetermined frequency between an open state in which the valve (8, 9, 13, 16, 20, 29) is partially or completely open, and a closed state deviating from the open state in which the valve (8, 9, 13, 16, 20, 29) is less open than in the open state, switched back and forth. [9] Method according to claim 8, characterized by that the vibrations are generated within a time interval of predetermined length immediately following the start of operation in order to generate excitation vibrations, taking into account at least one natural frequency of the component stored in the control electronics (31), and / or that the vibrations are generated within a time interval of predetermined length immediately preceding the end of operation in order to generate excitation vibrations, taking into account at least one natural frequency of the component stored in the control electronics (31). [10] Method according to claim 8 or 9, characterized by that an air compressor (12) of the cathode gas system (10) and / or a pump (25) of the cooling system (23) of the fuel cell system (1) are operated at a predetermined speed during the switch-on process and / or the switch-off process.

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