Patent Description:
The disclosure can be applied in relation to any type of vehicle operable from hydrogen or containing hydrogen tanks, e.g. hydrogen fuel for powering the propulsion system of the vehicle by means of a fuel cell system and/or a hydrogen internal combustion engine system. The vehicle may be a hybrid vehicle or an electric vehicle, such as a partly or fully electric vehicle. Although the disclosure will be described with respect to an electric truck, the disclosure is not restricted to this particular vehicle, but may also be used in other hybrid or electrical vehicles such as electric buses, and electric cars. The disclosure may also be applied in any other type of electric vehicle such as electric powered construction equipment, electric working machines e.g. wheel loaders, articulated haulers, dump trucks, excavators and backhoe loaders etc..

With the introduction of new energy storage systems in various types of vehicles, such as fuel cells in heavy-duty vehicles, there has been an increasing activity for developing new and adequate solutions for ensuring reliable operations of such systems, but also for other vehicle systems interacting with such systems. One area of particular interest in heavy-duty vehicles is the hydrogen supply system to vehicles containing e.g. fuel cell systems and/or hydrogen internal combustion engine, ICE, systems.

In contrast to vehicles operating based on a diesel ICE, vehicles operating on fuel cells or by means of a hydrogen ICE system may pose higher requirements on managing workshop maintenance and repair as well as roadside assistance of the vehicles. This is at least partly due to the low ignition energy of hydrogen. For example, in the event of an accident in which the hydrogen fuel system could be damaged such that the safe storage of the pressurized hydrogen gas is no longer ensured, there is a risk of the hydrogen gas leaking out from the system. When hydrogen gas blends with air at the release point or leakage point, all that is missing to have an explosion or fire is an ignition source.

Therefore, it is of interest to always implement high safety regulations for managing hydrogen vehicles. According to its Abstract, <CIT> discloses one example of monitoring a fuel tank of a vehicle, such as a hydrogen fuel tank of a vehicle.

It may also be advisable to verify that the hydrogen supply system has been purged to an appropriate low level before performing maintenance on the vehicle. In particular, maintenance activities that could lead to a release of hydrogen should not be initiated until the hydrogen has been purged from the system. By way of example, hydrogen gas should be depressurized to a safe location away from personnel, preferably upwards due to the buoyancy of hydrogen.

The hydrogen gas leak may exist before the vehicle maintenance or may be created by the repair technician when manipulating hardware elements of the hydrogen system or hardware elements located close to the hydrogen system which may shake and damage parts of the hydrogen system.

However, there is a challenge to purge hydrogen supply systems and hydrogen tanks of heavy-duty vehicles due to the size of the tanks. By way of example, it may take several hours or even days before the level of hydrogen is low enough to permit intervention and repair of the vehicle and/or the hydrogen supply system.

Therefore, there still remains a need for an improved control of purging hydrogen from a vehicle during maintenance work or after a vehicle accident. In addition, it would be desirable to further improve the overall performance of the purging process of hydrogen from heavy-duty vehicles.

It is thus an object of the present disclosure to at least partially overcome the above described deficiencies. The object is at least partly achieved by a method according to claim <NUM>. The object is also at least partly achieved by the other independent claims. The dependent claims relate to advantageous embodiments.

According to a first aspect of the disclosure, there is provided a method for controlling purging of hydrogen from a hydrogen circuit system of a vehicle. The hydrogen circuit system having a hydrogen conduit being arranged in fluid communication with at least one hydrogen tank. The method is implemented by a hydrogen control system comprising at least one processing circuitry. The method comprises deactivating one or more vehicle functions and vehicle systems into a non-ignitable state in response to a control signal indicative of a request for purging the hydrogen circuit system; and performing purging of the hydrogen circuit system when the one or more vehicle functions and vehicle systems being set into the non-ignitable state.

In this manner, the proposed method allows for purging hydrogen from a vehicle in a more reliable and efficient manner before initiating any maintenance work on the vehicle or after a vehicle accident. By the provision of a method which takes advantage of deactivating one or more vehicle functions and vehicle systems into a non-ignitable state in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system it becomes possible to purge hydrogen from the vehicle in a safer manner compared to hitherto known systems. In this manner, the proposed method provides for sequential action on different vehicle elements, components, and systems, to ensure safety. By way of example, the method may further comprise setting the vehicle in safe condition, including, but not limited to, shutting down any power / driving unit, setting the park brake and hazard warning indicators, inhibiting any vehicle element driving to spark generation or hot points.

In addition, the proposed method allows for purging hydrogen from the vehicle from a remote location.

In addition, the proposed method allows for reducing the downtime by having a safe mean to remotely purge one or several hydrogen tanks of the vehicle.

The method is thus at least partly based on the observation that hitherto known purging systems for vehicles often are based on alarm system, but lacks effective systems for purging hydrogen from vehicles in a reliable manner, e.g. controllable from a remote location from the vehicle.

Accordingly, in at least one example embodiment, the method is intended for controlling purging of hydrogen from the vehicle at remote location from the vehicle.

The proposed method is particularly suitable for electric vehicles including any one of a fuel cell system and a hydrogen ICE system.

Favourably, the method may be implemented by a remote-control system from the vehicle. The remote-control system may be arranged in communication with the one or more vehicle functions and vehicle systems and further in communication with a purging control arrangement arranged on the vehicle. The method may comprise performing purging of the hydrogen circuit system in response to a purging control signal from the remote-control system to the vehicle purging control arrangement.

Optionally, the vehicle purging control arrangement may comprise a controllable vent valve arrangement in fluid communication with the hydrogen circuit system, whereby performing purging of the hydrogen circuit system when the one or more vehicle functions and vehicle systems being set into the non-ignitable state is performed by operating the controllable vent valve arrangement to purge any hydrogen from the hydrogen circuit system. In this manner, the purging operation of hydrogen from the hydrogen circuit system can be controlled and completed in reliable and efficient manner.

Typically, the controllable vent valve arrangement is disposed in the hydrogen conduit of the hydrogen circuit system.

The controllable vent valve arrangement may be controllable by a plurality of control units arranged on the vehicle and in communication with the at least one processing circuitry.

The method may further comprise determining a hydrogen leaking state of any one of the at least one hydrogen tank and the hydrogen conduit. Typically, only the hydrogen tank or parts of the hydrogen conduit being subject to the hydrogen leak may be purged so as to ensure an empty system or component of hydrogen where there is a leak. Other hydrogen tanks or parts of the hydrogen circuit system that are still maintained in a leak-safe state may not necessarily be emptied of hydrogen or controlled for purging purposes.

In an example with a remote-control system, the control signal indicative of the determined hydrogen leaking state of any one of the at least one hydrogen tank and the hydrogen conduit may be transmitted to the processing circuity of the remote-control system.

The method may further comprise verifying that any equipment or systems of the vehicle in need of service is free of hydrogen before initiating maintenance of the equipment or systems. One example of an equipment or system is an ICE injection system. Another example of an equipment or system is a hydrogen tank. Yet another example of an equipment or system is a fuel cell stack. These types of equipment and systems may include one or more sensors for determining the state of the equipment or system. By way of example, the hydrogen tank may comprise a pressure sensor to monitor the pressure and to verify that the hydrogen tank is emptied.

It should be noted that the method can be implemented to monitor and control a number of different types of vehicle functions and vehicle systems, including various equipment, such as shutting down an ICE, stopping a cab heater, deactivating one or more electrical consumers producing heat or sparks. The electrical consumers may e.g. be any one of lighting system, high voltage battery system, a heater, a compressor, relays etc..

It is to be noted that the method may generally be performed by the hydrogen control system during use of the vehicle. Accordingly, any one of the steps of the method may be performed by the hydrogen control system during use of the vehicle.

According to one example embodiment, the steps of the method are performed in a sequence. However, at least some of the steps of the method can be performed concurrently. The method according to the example embodiments can be executed in several different manners. As mentioned above, the example embodiments of the method and the sequences of the methods, typically corresponding to the steps of the method, are executed by the hydrogen control system. In one example embodiment, any one of the steps of the method is performed by the hydrogen control system during use of the vehicle. The method may be continuously running as long as the vehicle is operative. The sequences of the method may likewise be performed by other types of components and by other technologies as long as the method can provide the associated functions and effects.

According to a second aspect of the disclosure, there is provided a computer program comprising program code means for performing the steps of the first aspect when the program is run on a computer or on processing circuitry of a control system.

According to a third aspect of the disclosure, there is provided a computer readable medium carrying a computer program comprising program code means for performing the steps of the first aspect when the program product is run on a computer or on processing circuitry of a control system.

Effects and features of the second and third aspects are largely analogous to those described above in relation to the first aspect.

According to a fourth aspect of the disclosure, there is provided a hydrogen control system for a vehicle. The vehicle comprises a hydrogen circuit system having a hydrogen conduit arranged in fluid communication with at least one hydrogen tank. The hydrogen control system comprises at least one processing circuitry in communication with a purging control arrangement arranged on the vehicle and configured to control purging of hydrogen from hydrogen circuit system. The hydrogen control system is further configured to deactivate one or more vehicle functions and vehicle systems into a non-ignitable state in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system, and perform purging of the hydrogen circuit system when the one or more vehicle functions and vehicle systems being set into the non-ignitable state.

Effects and features of the fourth aspect of the disclosure are largely analogous to those described above in connection with the first aspect.

By way of example, the purging control arrangement is configured to control purging of hydrogen from any one of the at least one hydrogen tank and the hydrogen conduit.

The hydrogen control system may be configured to determine an ignitable state of the one or more vehicle functions and vehicle systems, and, for any determined ignitable state of the one or more vehicle functions and vehicle systems, deactivating the one or more vehicle functions and vehicle systems into corresponding non-ignitable states.

As used herein, the term "ignitable state" refers to a condition of a vehicle system and/or a vehicle function that may cause hydrogen to ignite mixed even in small amounts with oxygen naturally present in the ambient air.

As used herein, the term "non-ignitable state" refers to a condition of a vehicle system and/or a vehicle function that is not causing a potential risk for flammability of hydrogen. In particular, the term "non-ignitable state" refers to a condition of a vehicle system and/or a vehicle function that is not causing a potential risk for flammability of hydrogen even if hydrogen would leak out from the hydrogen circuit system to the ambient atmosphere and/or become mixed with oxygen naturally present in the ambient air.

The hydrogen control system may comprise a remote-control system from the vehicle. The remote-control system may be arranged in communication with the one or more vehicle functions and vehicle systems and further in communication with the vehicle purging control arrangement. The vehicle purging control arrangement may be configured to control purging of the hydrogen circuit system in response to a purging control signal from the remote-control system.

The vehicle purging control arrangement may comprise a controllable vent valve arrangement disposed in the hydrogen circuit system. The controllable vent valve arrangement may be configured to purge any hydrogen from the hydrogen circuit system in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system and that the one or more vehicle functions and vehicle systems is set into the non-ignitable state.

The controllable vent valve arrangement may be disposed in the hydrogen circuit system downstream a pressure regulator. By the arrangement of the pressure regulator, it becomes possible to regulate the pressure of the hydrogen in the hydrogen circuit system.

The hydrogen circuit system may be in fluid communication with at least one hydrogen consumer. A hydrogen consumer may e.g. be any one of a fuel cell system and a hydrogen internal combustion engine system. The hydrogen circuit system may be in fluid communication with at least one fuel cell system. The fuel cell system may comprise one or more fuel cell stacks having multiple fuel cells. The hydrogen circuit system may be in fluid communication with the hydrogen internal combustion engine system.

The controllable vent valve arrangement may be disposed in the hydrogen circuit system downstream the hydrogen consumer. The controllable vent valve arrangement may be disposed in the hydrogen circuit system downstream the fuel cell stack.

The controllable vent valve arrangement may be controllable by a plurality of control units. In addition, or alternatively, the controllable vent valve arrangement may be controllable by the processing circuitry of the hydrogen control system.

The hydrogen control system may at least partly be integrated into a vehicle system. The hydrogen control system may at least partly be integrated into a hydrogen consumer system. By way of example, the hydrogen control system may at least partly be integrated into hydrogen fluid circuit control system. In other examples, parts of the hydrogen control system are integrated in the vehicle and other parts of the hydrogen control system may be arranged in communication with the parts arranged in the vehicle. Hence, parts of the hydrogen control system may be integral parts of the vehicle.

The vehicle may be an electric vehicle, such as a fully or hybrid electrical vehicle, comprising an energy storage system and an electric propulsion system. The vehicle may be an electrical, hybrid, or plug-in hybrid vehicle comprising an electrical motor, wherein the energy storage system provides power to the electrical motor for providing propulsion for the electrical, hybrid, or plug-in hybrid vehicle. The vehicle may typically comprise one or more drive units operable on hydrogen. By way of example, the vehicle may comprise a fuel cell system. In another example, the vehicle may comprise a hydrogen internal combustion engine system. In yet another example, the vehicle may comprise both a fuel cell system and a hydrogen internal combustion engine system. In other examples, the vehicle may comprise an electric propulsion system having both a battery system and a fuel cell system. The battery system and fuel cell system are generally in electrical connection with one or more electric machines.

The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting of the disclosure. It will be further understood that the terms "comprises" "comprising," "includes" and/or "including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The above, as well as additional objects, features and advantages of the present disclosure, will be better understood through the following illustrative and non-limiting detailed description of exemplary embodiments of the present disclosure, wherein:.

With reference to the appended drawings, below follows a more detailed description of embodiments of the disclosure cited as examples.

The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the disclosure are shown. The skilled person will recognize that many changes and modifications may be made within the scope of the appended claims. Similar reference characters refer to similar elements throughout the description.

Referring now to the drawings and to <FIG> in particular, there is depicted an exemplary vehicle, here illustrated as an electrical truck <NUM>. In this example, the electric truck <NUM> is a fully electrical vehicle. The electrical truck <NUM> comprises an electric propulsion system <NUM> configured to provide traction power to the vehicle. By way of example, the electric propulsion system <NUM> comprises an electrical energy storage system <NUM> and an electrical machine (not shown). The electric machine is a traction motor for providing traction power to the vehicle, i.e. for propelling the wheels of the vehicle. The energy storage system is here a fuel cell system <NUM>. Optionally the electric propulsion system may also include a battery system including one or more high voltage batteries. The fuel cell system <NUM> is connected to the electrical machine to provide power to the electrical machine, thereby the electrical machine can provide traction power to one or more ground engaging members, e.g. one or more wheels <NUM> and <NUM>. The electric machine may generally include a conventional electric motor.

The electrical propulsions system <NUM> may further comprise additional components as is readily known in the field of electrical propulsions systems, such as a transmission (not shown) for transmitting a rotational movement from the electric motor(s) to a propulsion shaft, sometimes denoted as the drive shaft (not shown). The propulsion shaft connects the transmission to the wheels. Furthermore, although not shown, the electrical motor is typically coupled to the transmission by a clutch.

The traction motor (electric machine) is arranged to receive electric power from any one of the battery (not shown) and the fuel cell system <NUM>. As further described herein, the fuel cell system <NUM> is here considered a vehicle system, or at least part of a vehicle system. In particular, the fuel cell system <NUM> is hydrogen consumer. Another example of a hydrogen consumer is a hydrogen internal combustion engine. The vehicle <NUM> also comprises a control unit <NUM> (see e.g. <FIG> or <FIG>) for controlling various operations and functionalities as will also be described in further detail below. The control unit is here the electronic control unit <NUM> of the vehicle <NUM>. In addition, as illustrated in <FIG>, the vehicle <NUM> is here in communication with a processing circuitry of a remote-control system <NUM>. As will be further described herein, the remote-control system <NUM> is here an integral part of a hydrogen control system <NUM> (see <FIG>). In addition, the control unit <NUM> may also be an integral part of the hydrogen control system <NUM>.

The fuel cell system <NUM> is of a conventional type and generally comprises one or more fuel cell stacks, each one having a number of fuel cells. By way of example, a number of fuel cells may form the so-called fuel cell stack. The fuel cells may likewise be arranged in multiple fuel cell stacks, each fuel cell stack comprising multiple fuel cells arranged in a stack configuration. Further, each one of the fuel cells making up the fuel cell stack, and thus the fuel cell system <NUM>, generally comprises an anode side receiving hydrogen as a fuel component and a cathode side receiving compressed air as another fuel component. While there are several different types of fuel cells, distinguished mainly by the type of electrolyte used, a so-called Proton Exchange Membrane (PEM) fuel cell is particularly suitable for use in heavy-duty vehicles, such as the vehicle <NUM> in <FIG>. Hence, the fuel cell system is here a PEM fuel cell system <NUM>. For the purposes of the proposed system and method, as described further herein, the fuel cell system <NUM> is schematically illustrated and only depicts the anode side, i.e. the cathode side is omitted for simplifying the illustration. Other components such as balance of plant components could also be included in the fuel cell system as are commonly used in the field of fuel cell system.

Turning now to <FIG>, there is depicted one example embodiment of a hydrogen control system <NUM> for controlling the hydrogen circuit system <NUM> containing and transferring hydrogen to one or more hydrogen consumers. The hydrogen control system <NUM> can be considered as hydrogen management control system and is configured to provide a safe handling of hydrogen during a leakage incident from the vehicle <NUM>. As will be further described herein, the hydrogen control system <NUM> here comprises a remote-control system <NUM> for a remote control of the hydrogen circuit system <NUM>.

As mentioned in relation to <FIG>, the vehicle system may be a fuel cell system <NUM>, or at least comprise a fuel cell system <NUM>. In <FIG>, the vehicle <NUM> comprises the fuel cell system <NUM>, as illustrated further in the enlarged view of <FIG>. The vehicle includes one or more hydrogen fuel system components for controlling supply of hydrogen to the anode side of the fuel cells of the fuel cell system <NUM>. These components may collectively be denoted as a hydrogen circuit system, as further described herein.

Generally, the flow of hydrogen to the fuel cell system <NUM>, or to any other types of hydrogen vehicle systems of the vehicle <NUM> is controlled during operation of the vehicle. By way of example, the control unit <NUM> is arranged and configured to control supply of hydrogen to a vehicle hydrogen consumer system comprising the fuel cell system <NUM>. Another example of a vehicle hydrogen consumer system operable on hydrogen is a hydrogen internal combustion engine system, as also illustrated in <FIG>.

While referring again to <FIG>, there is depicted a hydrogen circuit system <NUM> in communication with the hydrogen control system <NUM> for the vehicle <NUM>. The hydrogen circuit system <NUM> here comprises the fuel cell system <NUM>. The fuel cell system <NUM> is one example of a hydrogen consumer. The hydrogen circuit system <NUM> comprises a hydrogen conduit <NUM> and a hydrogen tank <NUM>. The hydrogen conduit <NUM> is configured to contain and transfer hydrogen <NUM>. The hydrogen circuit system <NUM> is an integral part of the vehicle <NUM>.

In some vehicles, the hydrogen circuit system <NUM> may include a plurality of hydrogen tanks. The hydrogen circuit system <NUM> is arranged in fluid communication with the hydrogen tank <NUM>. The hydrogen tank <NUM> is disposed in the hydrogen circuit system <NUM>. The hydrogen tank <NUM> and hydrogen conduit <NUM> may form a hydrogen gas fuel supply system. By way of example, the hydrogen circuit system <NUM> defines a hydrogen fuel supply line 51a configured to supply hydrogen gas to the fuel cell system <NUM>, as indicated by an arrow in the enlarged view of <FIG>. Hence, the hydrogen circuit system <NUM> provides a fluid communication between the hydrogen tank <NUM> and the fuel cell system <NUM>.

The hydrogen tank <NUM> is configured to contain the hydrogen fuel <NUM> in gaseous form. The hydrogen fuel <NUM> may also be partly arranged in liquid form in the hydrogen tank <NUM>. The hydrogen fuel <NUM> is supplied to the fuel cell system <NUM> from the hydrogen tank <NUM> via the hydrogen supply line 51a of the hydrogen conduit <NUM>. The hydrogen circuit system <NUM> is arranged and configured to contain and transport the hydrogen gas fuel <NUM>, as illustrated by the arrows in <FIG>, and may optionally include one or more additional hydrogen fuel system components such as a fluid medium pump, fuel filter etc. These components are of conventional types and thus not further described herein.

In addition, the hydrogen circuit system <NUM> here also comprises a hydrogen exhaust line 51b configured to transport exhaust gases from the fuel cell system <NUM>. The exhaust gases may here contain hydrogen residues etc. The hydrogen exhaust line 51b terminates with an exhaust outlet <NUM>.

The hydrogen circuit system <NUM> further comprises a vehicle purging control arrangement <NUM>, as illustrated in <FIG>, and sometimes simply denoted as the purging control arrangement. The purging control arrangement <NUM> is arranged in the vehicle <NUM>. In addition, the purging control arrangement <NUM> is arranged in fluid communication with the hydrogen circuit system <NUM>. In particular, the purging control arrangement <NUM> is configured to control purging of hydrogen from the hydrogen circuit system <NUM>. By way of example, the purging control arrangement <NUM> is arranged and configured to control purging of hydrogen from the hydrogen conduit <NUM>. In addition, or alternatively, the purging control arrangement <NUM> is arranged and configured to control purging of hydrogen directly from the hydrogen tank <NUM>.

In <FIG>, the purging control arrangement <NUM> comprises up to two controllable vent valve arrangements <NUM>, <NUM>. The controllable vent valve arrangements <NUM>, <NUM> are each disposed in the hydrogen conduit <NUM> of the hydrogen circuit system <NUM>. Each one of the controllable vent valve arrangements <NUM>, <NUM> is here controllable by the control unit <NUM>. Thus, each one of the controllable vent valve arrangements <NUM>, <NUM> is here controllable by the remote-control system <NUM> in communication with the control unit <NUM>.

The controllable vent valve arrangement <NUM> is disposed in the hydrogen circuit system <NUM> downstream the fuel cell system <NUM>. In particular, the controllable vent valve arrangement <NUM> is disposed in the hydrogen exhaust line 51b. One example of a controllable vent valve arrangement <NUM> is a conventional on-off valve unit.

The controllable vent valve arrangement <NUM> is here configured to purge hydrogen from the hydrogen exhaust line 51b of the hydrogen circuit system <NUM> in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system <NUM>. In addition, the controllable vent valve arrangement <NUM> is here configured to purge hydrogen from the hydrogen exhaust line 51b of the hydrogen circuit system <NUM> after receiving, i.e. in response to, a control signal indicative that the vehicle functions and/or vehicle systems are set into their corresponding non-ignitable states.

In other examples, the controllable vent valve arrangement <NUM> is configured to purge hydrogen from the hydrogen exhaust line 51b of the hydrogen circuit system <NUM> in response to a control signal indicative of data only confirming that the one or more vehicle functions and vehicle systems is set into the non-ignitable state. Hence, the control signal may necessarily not always be associated with hydrogen leakage. By way of example, such type of configuration may be useful / applicable in case of maintenance of elements of the hydrogen circuit due to damage or regular preventive maintenance. In some situations, the fuel cell system or fuel cells of the fuel cell system may need to be changed for maintenance purposes. In other situations, the fuel cell system or fuel cells of the fuel cell system may need to be upgraded. In these types of situations, it may be useful to purge hydrogen from the hydrogen circuit system <NUM> in response to a control signal indicative of data only confirming that fuel cell system is set into the non-ignitable state. i.e. there is neither any flow of hydrogen to the fuel cell system nor any hydrogen contained in the fuel cell system.

By purging hydrogen from the controllable vent valve arrangement <NUM>, it becomes possible to purge hydrogen after the fuel cell system <NUM>.

Further, as illustrated in <FIG>, the controllable vent valve arrangement <NUM> is disposed in the hydrogen circuit system <NUM> upstream the fuel cell system <NUM>. In particular, the controllable vent valve arrangement <NUM> is disposed in the hydrogen fuel supply line 51a. As such, the controllable vent valve arrangement <NUM> is arranged in-between the hydrogen tank <NUM> and the fuel cell system <NUM>. One example of a controllable vent valve arrangement <NUM> is a conventional on-off valve unit.

The controllable vent valve arrangement <NUM> is here configured to purge any hydrogen from the hydrogen fuel supply line 51a of the hydrogen circuit system <NUM> in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system <NUM>. In addition, the controllable vent valve arrangement <NUM> is configured to purge hydrogen from the hydrogen fuel supply line 51a of the hydrogen circuit system <NUM> after receiving, i.e. in response to, a control signal indicative that the vehicle functions and/or vehicle systems are set into their corresponding non-ignitable states.

In other examples, the controllable vent valve arrangement <NUM> is configured to purge hydrogen from the hydrogen fuel supply line 51a of the hydrogen circuit system <NUM> in response to a control signal indicative of data only confirming that the one or more vehicle functions and vehicle systems is set into the non-ignitable state. Hence, the control signal may necessarily not always be associated with hydrogen leakage. By way of example, such type of configuration may be useful / applicable in case of maintenance of elements of the hydrogen circuit due to damage or regular preventive maintenance, e.g. preventive replacement of hydrogen tank after a shock with an external element and/or replacement of the H2 pressure regulator that delivers too high/low pressure compared to its expectation. In these types of situations, it may thus be useful to purge hydrogen from the hydrogen circuit system <NUM> in response to a control signal indicative of data only confirming that fuel cell system is set into the non-ignitable state.

Moreover, as illustrated in <FIG>, the controllable vent valve arrangement <NUM> is disposed in the hydrogen fuel system <NUM> downstream a pressure regulator <NUM>. The pressure regulator is arranged and configured to lower the pressure from the hydrogen tank to an appropriate pressure for the fuel cell system <NUM>. By way of example, the pressure regulator <NUM> is arranged and configured to reduce the pressure of the hydrogen from <NUM> bars to a pressure that can be used by the fuel cells of the fuel cell system <NUM>, e.g. to a pressure level of about <NUM>-<NUM> bars. The pressure regulator <NUM> can also be controlled and operated by the control unit <NUM> and/or by the remote-control system <NUM>.

By purging hydrogen from the controllable vent valve arrangement <NUM>, it becomes possible to purge hydrogen from the fuel conduit 51a in a quick and efficient manner.

It should be readily appreciated that the purging control arrangement <NUM> can be provided with only one of the above-mentioned controllable vent valve arrangements <NUM>, <NUM>. Hence, in one example embodiment, the purging control arrangement <NUM> only includes the above-mentioned controllable vent valve arrangement <NUM> disposed in hydrogen exhaust line 51b. In another example embodiment, the purging control arrangement <NUM> only includes the above-mentioned controllable vent valve arrangement <NUM> disposed hydrogen fuel supply line 51a.

Moreover, as illustrated in <FIG>, the hydrogen circuit system <NUM> comprises a shut off valve <NUM> arranged in-between the hydrogen tank <NUM> and the pressure regulator <NUM>. The shut off valve <NUM> is thus disposed in the hydrogen supply line 51a. The shut off valve <NUM> is generally an integral part of the purging control arrangement <NUM> and thus also here an integral part of the hydrogen control system <NUM>. The shut off valve <NUM> is also here in communication with the control unit <NUM>. Thus, the shut off valve <NUM> is controllable by the control unit <NUM>. It should also be noted that if the hydrogen circuit system <NUM> includes several hydrogen tanks <NUM>, there is generally disposed one shut valve downstream each one of the hydrogen tanks. The function of the shut off valve is to prevent supply of hydrogen from the tank(s) <NUM> to the hydrogen conduit <NUM>. The shut off valve <NUM> is controlled by the control unit <NUM> to ensure a complete purge of the associated hydrogen tank <NUM>.

Turning again to the hydrogen control system <NUM> in <FIG>, there is depicted one example embodiment of a hydrogen control system <NUM> comprising the remote-control system <NUM>. The remote-control system <NUM> is arranged remotely from the vehicle <NUM>. By way of example, the remote-control system <NUM> may be arranged in a control-tower (not illustrated). As such, the remote-control system <NUM> is a telematic remote-control system <NUM>. Alternatively, or in addition, the remote-control system <NUM> may be arranged in another vehicle. Other possible locations for the remote-control system <NUM> is the integration of the remote-control system <NUM> in a fleet manager control system or the like.

The remote-control system <NUM> is arranged in communication with the one or more vehicle functions and vehicle systems and further in communication with the vehicle purging control arrangement <NUM>. In <FIG>, the vehicle system is a fuel cell system <NUM>. Hence, the remote-control system <NUM> is arranged in communication with the fuel cell system <NUM>.

The remote-control system <NUM> comprises a processing circuitry <NUM>, as illustrated in <FIG>. Favourably, the remote-control system <NUM> further comprises a storage memory <NUM> for storing relevant data relating to the control of the hydrogen circuit system <NUM> as well as the control of the components making up the hydrogen control system <NUM>. The processing circuitry <NUM> is here in communication with the purging control arrangement <NUM>. In <FIG>, the processing circuitry <NUM> is in communication with the purging control arrangement <NUM> via the control unit <NUM>. The control unit <NUM> is generally an integral part of the purging control arrangement <NUM> and the hydrogen control system <NUM>.

The control unit <NUM> is here configured to determine an ignitable state of the one or more vehicle functions and vehicle systems. By way of example, the ignitable state of a vehicle system is determined by comparing the state of the vehicle system with a threshold value. The threshold value is here indicative of the risk for causing an ignition. By way of example, the threshold may be related to the heat source, the spark producer of the vehicle function or vehicle system. In addition, for any determined ignitable state of the one or more vehicle functions and vehicle systems, the control unit <NUM> is also configured to deactivate the one or more vehicle functions and vehicle systems into corresponding non-ignitable states. By way of example, the non-ignitable state of a vehicle system is determined by comparing the state of the vehicle system with a corresponding threshold value. In a similar vein, the threshold value is here indicative of the risk for causing an ignition. By way of example, the threshold may be related to the heat source, the spark producer of the vehicle function or vehicle system. Hence, in the example when the control unit <NUM> is an integral part of the hydrogen control system <NUM>, the hydrogen control system <NUM> is here configured to determine an ignitable state of the one or more vehicle functions and vehicle systems. In addition, for any determined ignitable state of the one or more vehicle functions and vehicle systems, the hydrogen control system <NUM> is also configured to deactivate the one or more vehicle functions and vehicle systems into corresponding non-ignitable states.

In this example embodiment, the hydrogen control system <NUM> is further configured to deactivate one or more vehicle functions and vehicle systems into a non-ignitable state in response to a control signal indicative of hydrogen leaking from the hydrogen circuit system <NUM>. A vehicle system can e.g. be deactivated into its non-ignitable state by inhibiting any electrical power of some part of the vehicle where there are relays, light bulbs, accessories and/or electric motors that can create sparks. In a similar vein, for a vehicle system or vehicle function relating to, or corresponding to, the hydrogen ICE, the non-ignitable state can be set by requesting the stop of the hydrogen ICE.

Moreover, the hydrogen control system <NUM> is configured to perform purging of the hydrogen circuit system <NUM> when the one or more vehicle functions and vehicle systems are set into the non-ignitable state.

Turning again to the purging control arrangement <NUM> in <FIG>, the purging control arrangement <NUM> is configured to control purging of the hydrogen circuit system <NUM> in response to a purging control signal from the remote-control system <NUM>.

In order to ensure a reliable operation of the vehicle <NUM>, there may generally also be useful to monitor the supply of hydrogen in the hydrogen circuit system <NUM>, e.g. by monitoring or estimating the hydrogen pressure in the hydrogen circuit system <NUM>, so as to avoid detrimental leakage and/or a malfunction of the hydrogen circuit system <NUM>, as well as reduce the impact from an unavoidable hydrogen leakage, e.g. due to an accident. As such, the hydrogen control system <NUM> is here also arranged and configured to monitor the supply of hydrogen in the hydrogen circuit system <NUM>. The operation of monitoring the supply of hydrogen in the hydrogen circuit system <NUM> can be performed by one or more sensors (not illustrated).

In addition, the hydrogen control system <NUM> is here also arranged and configured to control supply of hydrogen to various vehicle systems operable by hydrogen. In <FIG>, the control unit <NUM> of the hydrogen control system <NUM> is configured to control supply of hydrogen from the hydrogen tank <NUM> to the fuel cell system <NUM> via the hydrogen fuel supply line 51a.

To sum up, the remote-control system <NUM> is configured to communicate with the control unit <NUM> so as to deactivate at least the fuel cell system <NUM> into the non-ignitable state in response to the control signal indicative of a request for purging the hydrogen circuit system <NUM>. Optionally, the remote-control system <NUM> is also configured to deactivate any other vehicle functions and vehicle systems into their non-ignitable states in response to the control signal indicative of the request for purging the hydrogen circuit system <NUM>.

After the fuel cell system <NUM> is set in its non-ignitable state, the remote-control system <NUM> is configured to perform purging of the hydrogen circuit system <NUM>. Typically, the remote-control system <NUM> is also configured to verify that all other functions and systems being potential ignitable sources are set in their corresponding ignitable states prior to commence the operation of purging of the hydrogen circuit system <NUM>.

The remote-control system <NUM> initiates purging of the hydrogen circuit system by transmitting the purging control signal to the vehicle purging control arrangement <NUM>.

Upon receiving the purging control signal from the remote-control system <NUM>, the vehicle purging control arrangement <NUM> is operable to control any one of the controllable vent valve arrangements <NUM>, <NUM> to purge hydrogen from the hydrogen circuit system <NUM>.

The purging control signal may either be linked to a detected hydrogen leakage from the hydrogen circuit system or linked to a user signal from an operator of the remote-control system <NUM>.

The purging operation of the purging control arrangement <NUM> of the hydrogen control system <NUM> can be performed in several different manners. By way of example, the purging operation can be provided by so called natural venting. In addition, or alternatively, the purging operation can be provided by so called pressurizing-venting cycle purge, such as pressurizing-venting by using pressured air from the compressed air tank. This compressed air may be supplied from a compressed air system (not illustrated) for the braking and suspension system. Such compressed air system can be arranged in fluid communication with the hydrogen circuit system <NUM> so as to provide for pushing the hydrogen out from the hydrogen circuit system. Natural venting and pressurizing-venting cycle purge are well-common operations for purging hydrogen from a circuit, and thus not further described herein.

Moreover, in the illustrated example, only the hydrogen tank <NUM> or parts of the hydrogen conduit <NUM> being subject to the hydrogen leakage are purged so as to ensure an empty system. Other hydrogen tanks or parts of the hydrogen circuit system that are still maintained in a leak-safe state may not be emptied of hydrogen or controlled for purging purposes.

By way of example, the hydrogen leakage state is detected by a sensor (not illustrated). The sensor can be arranged adjacent the hydrogen circuit system <NUM>. In other examples, the sensor can even be arranged on another location of the vehicle <NUM> or located in a workshop premises or nearby a technician. Optional, the technician can also notice a whistling from the hydrogen circuit system <NUM> without the need to wait for a confirmation from the hydrogen sensor disposed in or adjacent the hydrogen circuit system <NUM>.

In other systems and examples, the hydrogen leakage state can be detected and/or determined by an unexpected pressure drop on the hydrogen circuit system <NUM>. Hence the hydrogen leakage state can be triggered in several different ways.

<FIG> illustrate another hydrogen circuit system <NUM> according to one example embodiment. In this example embodiment, the hydrogen consumer is a hydrogen internal combustion engine system <NUM>. The hydrogen internal combustion engine system <NUM> generally comprises one or more cylinders <NUM> having corresponding combustion chamber and reciprocating pistons (not illustrated). As shown in <FIG>, the hydrogen circuit system <NUM> comprises the hydrogen tank <NUM> in fluid communication with hydrogen internal combustion engine <NUM>. As described in relation to <FIG>, the hydrogen consumer, here corresponding to the hydrogen internal combustion engine <NUM>, is in fluid communication with the hydrogen tank <NUM> via the hydrogen conduit <NUM>, in particular via the hydrogen supply line 51a. In a similar vein, an exhaust side of the hydrogen internal combustion engine <NUM> is in fluid communication with the hydrogen exhaust line 51b.

Moreover, in <FIG>, the controllable vent valve arrangement <NUM> of the vehicle purging control arrangement <NUM> is disposed in the hydrogen supply line 51a. The control of the controllable vent valve arrangement <NUM> and the purging of hydrogen from the hydrogen circuit system <NUM> via the controllable vent valve arrangement <NUM> corresponds to the control and purging of hydrogen from the hydrogen circuit system <NUM> in <FIG>. Favourably, although not illustrated in <FIG>, the system may also comprise the shut off valve <NUM> arranged in-between the hydrogen tank <NUM> and the pressure regulator <NUM>. Hence, the purging of hydrogen from the hydrogen circuit system <NUM> is here also controlled by the remote-control system <NUM> of the hydrogen control system <NUM>.

In regard to the arrangement of the control unit <NUM> for any one of the hydrogen control system <NUM> in <FIG> and <FIG>, it may also be possible to control purging by a control unit having a first sub-control unit 92a and a second sub-control unit 92b. The first sub-control unit 92a and the second sub-control unit 92b here forms the control unit <NUM>. In <FIG>, there is depicted an example of a hydrogen control system <NUM> comprising a plurality of control units in the form of the first sub-control unit 92a and the second sub-control unit 92b. In this example embodiment, the controllable vent valve arrangement <NUM> is controllable by the first and second control units 92a, 92b. Each one of the first and second control units 92a, 92b is arranged in communication with the remote-control system <NUM> of the hydrogen control system <NUM>. In addition, each one of the first and second control units 92a, 92b is arranged in communication with the controllable vent arrangement <NUM> of the hydrogen circuit system <NUM>. By this arrangement, it becomes possible to provide an even more secure control of the controllable vent valve arrangement <NUM> during operation of the hydrogen circuit system <NUM>, and also during purging of hydrogen from the hydrogen circuit system <NUM>. By way of example, the first sub-control unit 92a is configured to set the control of the controllable vent valve arrangement <NUM>, while the second sub-control unit 92b is configured to enable the control of the control of the controllable vent valve arrangement <NUM>, i.e. to ensure that control signal is forwarded electrically to the controllable vent valve arrangement <NUM>. Hereby, it becomes possible to improve the robustness of the control of the system by reducing the risk of having one of the control functionalities to fail during the purging control of the system <NUM>.

In all example embodiments described in relation to <FIG>, the control unit <NUM> may be an electronic control unit. By way of example, the electronic control unit <NUM> is configured to operate the hydrogen consumer, such as the fuel cell system <NUM> and/or the hydrogen internal combustion engine <NUM>. In addition, the electronic control unit <NUM> is configured to operate the hydrogen control system <NUM> as well as any hydrogen purging operation from the hydrogen circuit system <NUM> in response to the control signal. Moreover, the electronic control unit <NUM> is configured to operate the hydrogen control system <NUM> according to any one of the example embodiments of a method, as described in any one of the <FIG>. The control unit <NUM> is here configured to gather and/or receive operating data relating to the hydrogen circuit system <NUM> and the pressure level of the hydrogen circuit system <NUM>. The control unit <NUM> is also configured to transmit the gathered or received data to the processing circuitry <NUM> of the remote-control system <NUM> for further processing.

The communication between the control unit <NUM> and the processing circuitry <NUM> of the remote-control system <NUM> can be made by a wire connection, wirelessly or by any other technology such as Bluetooth or the like. Analogously, the communication between the control unit <NUM>, the remote-control system <NUM> and any sensor at or adjacent the hydrogen circuit system <NUM> may be made by a wire connection, wirelessly or by any other technology such as Bluetooth or the like. Examples of communication system may thus be any one of a telecommunication mobile network, QR code readable by one camera arranged on the vehicle, wireless remote control system, driver key fob, workshop vehicle interface system, instructions from any type of back office system through a telematic gateway.

Although not illustrated, the remote-control system <NUM> optionally comprises a user communication device in networked communication with the processing circuitry <NUM> of the remote-control system <NUM>. By way of example, the user communication device may be a touch screen or a portable device such as cellular phone. The user communication device may in other examples be arranged in a dashboard of the vehicle and/or in another vehicle.

The user communication device is configured to communicate status of the hydrogen circuit system <NUM> and alert the user of any potential or ongoing hydrogen leakage from the hydrogen circuit system <NUM> of the vehicle <NUM>. The alert(s) may be in the form of a visual warning that the hydrogen level is below a threshold value. In addition, or alternatively, the alert may contain a digit indicative of the pressure. In response to the alert on the user communication device, a technician may decide to control purging of the hydrogen circuit system <NUM> as described herein. In other situations, the technician may decide to control purging of the hydrogen circuit system <NUM> as desired or needed for reasons of upcoming maintenance work.

In the above situations, the remote-control system <NUM> will be arranged and configured to ensure that all vehicle functions and/or vehicle systems are set into non-ignitable states before initiating purging of hydrogen from the hydrogen circuit system <NUM>.

In order to describe the hydrogen control system <NUM> of the vehicle <NUM> in further detail, reference is now made to <FIG> which illustrates various example embodiments thereof. The hydrogen control system <NUM> is operable by a method according to any one of the example embodiments as described in any one of the <FIG>.

Typically, although strictly not required, the hydrogen control system <NUM> is controlled by the remote-control system <NUM> so as to perform the method according to any one of the example embodiments as described in any one of the <FIG>.

Turning now to <FIG>, there is depicted a flowchart of a method according to an example embodiment of the disclosure. The method <NUM> is intended for controlling purging of hydrogen from the hydrogen circuit system <NUM> of the vehicle <NUM>, as described in relation to <FIG>, <FIG> and <FIG>. The sequences of the method are typically performed by the processing circuitry <NUM> of the remote-control system <NUM>, as described herein.

In <FIG>, the method comprises a step of deactivating S20 one or more of the vehicle functions and vehicle systems of the vehicle <NUM> into non-ignitable states in response to the control signal indicative a of request for purging the hydrogen circuit system <NUM>.

In this example the control signal contains data indicative of hydrogen leaking from the hydrogen conduit <NUM>. Accordingly, by way of example, the method comprises the step of deactivating S20 one or more vehicle functions and vehicle systems into non-ignitable states in response to a control signal indicative of hydrogen leaking from the hydrogen conduit <NUM>.

Subsequently, the method comprises a step of performing S30 purging of the hydrogen circuit system <NUM> when the one or more vehicle functions and vehicle systems have been set into corresponding non-ignitable states.

By way of example, the actual purging operation of the hydrogen circuit system <NUM> is performed by the vehicle purging control arrangement <NUM> in response to the transmitted purging control signal from the remote-control system <NUM> to the vehicle purging control arrangement <NUM>.

Optionally, the method initially comprises a step of determining S10 a hydrogen leaking state of any one of the at least one hydrogen tank <NUM> and the hydrogen conduit <NUM>. As mentioned herein, the hydrogen leaking state may be detected and determined in several ways. By way of example, the remote-control system <NUM> may be arranged in communication with a data acquiring unit (not illustrated) on the vehicle <NUM>. Generally, the control unit of the vehicle may also be arranged in communication with the data acquiring unit.

The data acquiring unit is adapted to gather pressure state etc. from the hydrogen circuit system <NUM> during use of the vehicle <NUM>. The data acquiring unit may comprise or communicate with a pressure sensor (not shown) arranged adjacent or in the hydrogen circuit system <NUM> for monitoring the pressure in the hydrogen circuit system <NUM>. In this manner, the hydrogen control system <NUM> is arranged and configured to monitor the hydrogen circuit system <NUM> so as to detect if there is any ongoing hydrogen leakage from the conduit <NUM> of the tank(s) <NUM>.

Depending on the outcome of the above monitoring operation, the hydrogen control system <NUM> is configured to perform the purging operation of the hydrogen circuit system <NUM> upon receiving the control signal by operating the purging control arrangement <NUM>.

Another example embodiment of the method is depicted in <FIG>. The method illustrated in <FIG> is based on the sequence of the method according to example embodiment in <FIG>. In addition, in <FIG>, there is the initial step of determining S10 a hydrogen leaking state of any one of the at least one hydrogen tank <NUM> and the hydrogen conduit <NUM>.

Moreover, as illustrated in <FIG>, the method <NUM> after step S20 and step S30 here performs the step of verifying S40 that any equipment or system of the vehicle in need of service is free of hydrogen before initiating maintenance of the equipment or system.

Typically, the method as illustrated in <FIG>, may also comprise the step of communicating the advancement of the purging operation to the remote-control system <NUM>.

It should be noted that the example embodiment as described in relation to <FIG> may be combined with any one of the steps from the above example embodiments, e.g. the example embodiments described in relation to <FIG>.

Favourably, data relating to the operations of the hydrogen control system <NUM> are stored in a memory <NUM> of the hydrogen control system <NUM>. By way of example, the remote-control system <NUM> comprises the memory <NUM>. The memory <NUM> is arranged in communication with the processing circuitry <NUM> of the remote-control system <NUM>.

While the remote-control system <NUM> may generally be a stationary remote source operated by a technician or so, it should be noted that the remote-control system <NUM> and the processing circuitry <NUM> may likewise be integral parts of another vehicle in communication with the hydrogen circuit system <NUM> of the vehicle <NUM>. In other examples, the remote-control system <NUM> is part of a control tower operated by a fleet manager and the like, operating a number of vehicles within a logistics area.

The disclosure also relates to the hydrogen control system <NUM>. The hydrogen control system <NUM> comprises the remote-control system <NUM> and the processing circuitry <NUM>. The remote-control system <NUM> is configured to perform a method according to any one of the example embodiments as described in relation to the <FIG>. In addition, the disclosure relates to the vehicle <NUM> comprising the hydrogen control system <NUM> according to any one of the example embodiments as described in relation to the <FIG>. In addition, the disclosure relates to a computer program comprising program code means for performing the steps of the method as described in relation to the <FIG>, when the program is run on a computer. In addition, the disclosure relates to a computer readable medium carrying a computer program comprising program means for performing the steps of the method as described in relation to the <FIG> when the program means is run on a computer.

Thanks to the present disclosure, as exemplified by the example embodiments in <FIG>, it becomes possible to provide an improved purging control strategy for the vehicle <NUM> in which a vehicle can be purged from hydrogen in an efficient and reliable manner. In particular, it becomes possible to provide an improved purging control strategy for the vehicle <NUM> in which a vehicle being subject to a hydrogen leaking can be purged from hydrogen in an efficient and reliable manner.

As mentioned above, it is to be noted that the steps of the method are typically performed by the hydrogen control system <NUM>, including the control unit <NUM>, during use of the vehicle <NUM>. Thus, the hydrogen control system <NUM> is configured to perform any one of the steps of any one of the example embodiments as described above in relation to the <FIG>. A control unit may include a microprocessor, microcontroller, programmable digital signal processor or another programmable device. Thus, each one of the control units comprises electronic circuits and connections (not shown) as well as processing circuitry (e.g. processing circuitry <NUM> or processing circuitry of the control units <NUM>, <NUM>, 92a, 92b) such that the corresponding control unit can communicate with different parts of the truck such as the brakes, suspension, driveline, in particular an electrical engine, an electric machine, fuel cell system, hydrogen internal combustion engine, a clutch, and a gearbox in order to at least partly operate the truck. Each one of the control units may comprise modules in either hardware or software, or partially in hardware or software and communicate using known transmission buses such as CAN-bus and/or wireless communication capabilities. The processing circuitry may be a general purpose processor or a specific processor. Each one of the control units comprises a non-transitory memory for storing computer program code and data upon. Thus, the skilled addressee realizes that each one of the control units may be embodied by many different constructions.

The control functionality of the present disclosure may be implemented using existing computer processors, or by a special purpose computer processor for an appropriate system, incorporated for this or another purpose, or by a hardwire system. Embodiments within the scope of the present disclosure include program products comprising machine-readable medium for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed a machine-readable medium. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data which cause a general-purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions.

It should be noted that the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> can be performed from several locations, as described herein. Hence, the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> can be performed remotely by the remote-control system <NUM> and the processing circuitry <NUM>. However, the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> can also be performed at least partly from the control unit <NUM> of the vehicle. In addition, or alternatively, the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> can also be performed at least partly from a control unit <NUM> of another vehicle.

In addition, if the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> is performed remotely by the remote-control system <NUM> and the processing circuitry <NUM>, the processing circuitry <NUM> may communicate with any the control units <NUM> of the vehicle and the hydrogen circuit system <NUM>, which then control the purging control arrangement <NUM> and its controllable vent valve arrangement(s) <NUM> and/or <NUM>. Alternatively, or in addition, if the method for controlling purging of hydrogen from the hydrogen circuit system <NUM> is performed remotely by the remote-control system <NUM> and the processing circuitry <NUM>, the processing circuitry <NUM> may communicate directly with the purging control arrangement <NUM> and its controllable vent valve arrangement(s) <NUM> and/or <NUM>.

Although the Figures may show a sequence, the order of the steps may differ from what is depicted. Also, two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

Claim 1:
A method (<NUM>) for controlling purging of hydrogen from a hydrogen circuit system (<NUM>) of a vehicle (<NUM>), said hydrogen circuit system having a hydrogen conduit (<NUM>) being arranged in fluid communication with at least one hydrogen tank (<NUM>), said method being implemented by a hydrogen control system (<NUM>) comprising at least one processing circuitry (<NUM>), the method comprising:
deactivating (S20) one or more vehicle functions and vehicle systems into a non-ignitable state in response to a control signal indicative of a request for purging the hydrogen circuit system, and
performing (S30) purging of the hydrogen circuit system when said one or more vehicle functions and vehicle systems being set into the non-ignitable state.