Energy management system, aircraft having the same, and method for managing energy

Abstract

An energy management system, an aircraft having the system, and a method of managing energy. Wherein, the energy management system includes: a fuel cell configured to convert chemical energy into electrical energy; at least one energy source for providing electrical energy; at least one electrical load; an electrical bus electrically coupled to the fuel cell, the at least one energy source, and the at least one electrical load; and a controller configured to control the at least one electrical load to ensure that a minimum load is applied to the fuel cell. In addition, the aircraft includes such an energy management system. A method for managing energy in the system includes: electrically coupling the fuel cell, the at least one energy source, and the at least one electrical load through an electrical bus; and controlling the at least one electrical load to ensure that a minimum load is applied to the fuel cell.

Description

Technical Field

[0001] The present invention relates to an energy management system for ensuring a minimum load of a fuel cell, an aircraft having such an energy management system, and a method for ensuring a minimum load of a fuel cell. In particular, the present invention relates to an energy management system having an electrical bus electrically coupled to a fuel cell, an energy source, and an electrical load, wherein a controller can control the electrical load to ensure that a minimum load is applied to the fuel cell. The present invention also relates to an aircraft having such an energy management system, and a method for electrically coupling a fuel cell, an energy source, and an electrical load, and controlling the electrical load to ensure a minimum load of the fuel cell. Background Art

[0002] Fuel cells have become an increasingly important energy source, for example, in applications for aircraft including commercial aircraft and unmanned aerial vehicles (UAVs). For example, since solar energy can be used for most systems over a relatively long service life, solar cells can be combined with renewable fuel cells to provide electrical energy for the consumables of the system.

[0003] However, due to fluctuations in the power required by the electrical load of the system, the power scheme applied to such renewable fuel cells may cause damage to the fuel cell. Summary of the Invention

[0004] Therefore, an object of the present invention is to provide an energy management system, an aircraft, and a method for managing energy, which can prevent damage to the fuel cell and delay its lifespan.

[0005] According to a first exemplary aspect for understanding the present invention, an energy management system includes: a fuel cell configured to convert chemical energy into electrical energy; at least one energy source for providing electrical energy; at least one electrical load; and an electrical bus electrically coupled to the fuel cell, the at least one energy source, and the at least one electrical load. Thus, the fuel cell and the at least one energy source supply electrical energy to the at least one electrical load. For example, the electrical bus can be connected to the fuel cell and the at least one energy source by wires, and / or, the electrical bus can be formed by wires to electrically couple the fuel cell, the at least one energy source, and the at least one electrical load.

[0006] The energy management system may further include a controller configured to control at least one electrical load to ensure that a minimum load is applied to the fuel cell. In other words, the minimum power limit of the fuel cell is always to be followed. This avoids the wear of the fuel cell, which otherwise, if the fuel cell is operated with a smaller load (below the minimum load), may cause the chemical reaction in the fuel cell to stop and may cause the fuel cell to dry out. For example, in order to operate the fuel cell in a low power mode, only a small amount of fuel needs to be supplied to the fuel cell, which may not be sufficient to activate the operation of the fuel cell or (when the fuel cell is already in an operating state) may prevent the normal operation of the fuel cell. As a result, the fuel cell may be alternately activated and deactivated, which results in the wear of the fuel cell.

[0007] The fuel cell may also be operated in a high power mode. This high power mode may refer to operating the fuel cell between 50% and 70% fuel efficiency, preferably at a fuel efficiency of approximately 60%. The controller may be configured to control at least one electrical load such that: the bus load (all loads connected to the bus) requires electrical energy corresponding to the minimum load, which may be between 45% and 60% fuel efficiency, preferably approximately 50% fuel efficiency. Thus, when the fuel cell is activated, it will almost always operate at the power of the optimal efficiency, which is generally close to the minimum power that the fuel cell can provide. In other words, the fuel cell may be operated in a high power mode and at a medium efficiency point, so that the fuel cell can be designed and sized for this specific power mode rather than for a wide frequency of the required power levels. Therefore, the weight and size of the fuel cell can be optimized, which increases the power-to-weight ratio (optimal for an aircraft), and at the same time, the life of the fuel cell can be extended due to less wear of the fuel cell.

[0008] According to a variant of an embodiment, the controller may further control at least one electrical load such that the power provided by the fuel cell remains constant. In other words, within a preset time period, the electrical energy consumed on the electrical bus (i.e., all loads connected to the bus) will be controlled by the controller so that the fuel cell can operate at a constant electrical energy output level. This constant operation of the fuel cell avoids the wear of the fuel cell by avoiding several load changes. Such load changes may be caused by a change in the energy consumption of at least one electrical load connected to the electrical bus and / or by a change in the electrical energy provided to the electrical bus by at least one energy source. Alternatively or additionally, the controller may control at least one electrical load such that: the power provided by the fuel cell is greater than the minimum power required by at least one electrical load and / or the fuel cell operates at the optimal efficiency.

[0009] Therefore, even if the power consumption on the electrical bus and / or the electrical energy provided by at least one energy source varies over time, the fuel cell can operate at a minimum load and / or in a constant manner, and / or, operate with optimal efficiency. In other words, the electrical energy consumed on the electrical bus (i.e., all loads connected to the bus) is controlled by the controller such that: the fuel cell can operate at least at a minimum electrical energy output level, and / or, the electrical power provided by the fuel cell (the electrical energy output level within a predetermined time period) is constant. Due to the optimal fuel efficiency and optimal power mode of the fuel cell, the fuel cell can operate with minimum losses.

[0010] According to another embodiment variant, the controller is configured to activate or deactivate at least one electrical load based on the electrical power provided by at least one energy source. Therefore, the electrical energy provided by at least one energy source is used as the basis for the controller to activate or deactivate at least one electrical load. The controller can control one or more of the at least one electrical load to balance the electrical energy provided by at least one energy source. It should be understood that the controller can be configured to not only activate or deactivate an electrical load, but also operate an electrical load at a specific power level (energy consumption level) based on the electrical power provided by at least one energy source, thereby controlling the electrical load.

[0011] Alternatively or additionally, the energy management system can include multiple electrical loads, and the controller is further configured to activate or deactivate one of the multiple electrical loads based on the power consumed by the remaining loads among the multiple electrical loads except this one load. It should be understood that the controller can be configured to not only activate or deactivate an electrical load, but also operate this electrical load based on the power consumed by the remaining loads among the multiple electrical loads except this one load (energy consumption level), thereby controlling the electrical load.

[0012] According to another embodiment variant, the controller is further configured to keep the bus load power of the electrical bus constant within a time period, during which the fuel cell operates in a predetermined power mode. This process is achieved by the controller activating, deactivating, and / or operating the electrical load such that the electrical energy consumed on the electrical bus is constant. And this enables the fuel cell to operate in a predetermined power mode within a time period. For example, the controller can determine the predetermined power mode and can control the fuel cell accordingly. Therefore, the controller can set the operating mode of the fuel cell. This also reduces the losses of the fuel cell because when the predetermined power mode is selected, the operation of the fuel cell can be kept constant. The predetermined power mode can correspond to a specific fuel efficiency level, for example, a fuel efficiency of 45%, 50%, 55%, 60%, etc.

[0013] In another implementation variant, at least one electrical load includes one or more of the following: an electrolyzer, a storage battery, an electric motor mechanically coupled to a drive unit, an electric heater, and a payload. In an energy management system installed in a vehicle (e.g., an aircraft, a road vehicle (such as a car), a floating vehicle (such as a ship), etc.), an electric motor mechanically coupled to a drive unit may occur. The drive unit may be a propeller (for aircraft and floating vehicles) or a drive wheel (for road vehicles). The electric heater can be used to heat fuel, the payload, or other items that must be protected from cold. The payload as an electrical load refers to any electrical device that requires electrical energy, such as a controller, a signal device, a communication device, a monitoring device, an electric (servo-electric) motor, etc. The controller may be configured to operate each of the at least one electrical load such that: ensuring that a minimum load is added to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by at least one electrical load, and / or the fuel cell operates at an optimal efficiency.

[0014] The fuel cell together with the electrolyzer can form a regenerative fuel cell, and the electrolyzer is also capable of decomposing a chemical substance into fuel and residues, for example, decomposing water into hydrogen and oxygen. In this regard, the controller may be configured to operate the electrolyzer such that: ensuring that a minimum load is added to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by at least one electrical load, and / or the fuel cell operates at an optimal efficiency. In other words, at any given time, the amount of fuel (e.g., hydrogen) generated by the electrolyzer corresponds to the electrical energy available on the electrical bus (provided by the fuel cell and at least one energy source connected to the electrical bus) minus the electrical energy consumed by all electrical loads other than the electrolyzer. Otherwise, the electrical energy will be wasted by an electric heater that does not have any specific heating function or a similar less useful electrical energy consumer. Therefore, different from the waste of electrical energy caused by changing electrical energy supply and / or changing electrical energy consumption, when attempting to operate the fuel cell at or above the minimum load (close to the minimum power output of the fuel cell), the excess electrical energy will be stored in the form of fuel (e.g., in the form of reaction gas) to operate the fuel cell.

[0015] According to another embodiment variant, the energy management system may further include a fuel tank that is fluidly coupled to the electrolyzer and is adapted to store the fuel generated by the electrolyzer and supply the stored fuel to the fuel cell. The fuel tank may be part of the regenerative fuel cell and / or the electrolyzer. Additionally, the fuel produced by the electrolyzer may be compressed, for example, by a pump or a compressor before being stored in the fuel tank. In a particular variant of the energy management system, the regenerative fuel cell, the electrolyzer, and the fuel tank form a unit, i.e., are mounted together to form a compact structural unit.

[0016] If at least one electrical load includes an electric motor that is mechanically coupled to a drive unit of a vehicle, the controller may be configured to operate the electric motor such that: a minimum load is ensured to be applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency. For example, the controller may control the electric motor such that the vehicle performs a climbing action and / or accelerates, for example, by increasing the electric motor and thus increasing the rotational speed of the drive unit. The drive unit may be a propeller or a drive wheel, the rotational speed of which is proportionally dependent on the rotational speed of the electric motor. Thus, when attempting to operate the fuel cell at or above the minimum load (close to the minimum power output of the fuel cell), no electrical energy will be wasted due to a changed electrical energy supply and / or a changed electrical energy consumption, but rather the excess electrical energy will be stored in the form of the mechanical potential energy and / or kinetic energy of the vehicle integrated with the energy management system.

[0017] According to another embodiment variant, the at least one electrical load may include a storage battery. The controller is then configured to operate the storage battery such that: a minimum load is ensured to be applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency. In other words, when attempting to operate the fuel cell at or above the minimum load (close to the minimum power output of the fuel cell), the controller is able to charge the storage battery to store energy, rather than wasting electrical energy due to a changed electrical energy supply and / or a changed electrical energy consumption.

[0018] In another implementation variant, the at least one energy source includes one or more of the following: at least one solar panel configured to convert light into electrical energy; a storage battery; and an electric motor mechanically coupled to a propeller and configured to operate as a generator during a deceleration or descent period. Thus, the at least one energy source supplies electrical energy to all energy consumers of the energy management system via an electrical bus. The electrical energy generated by the at least one energy source can vary over time, while the electrical energy consumed by the at least one electrical load can be constant (or can also vary over time independently of the supplied energy). Therefore, the controller needs to control the at least one electrical load to compensate for this variation in the available / consumed electrical energy.

[0019] For example, the electrical energy generated by the at least one solar panel changes due to, for example: the angle of incidence of sunlight on the at least one solar panel; the at least one solar panel being at least partially in shadow; and / or sunrise or sunset. The storage battery can supply electrical energy at a specific level, which will decrease if the battery charge is low. The electric motor can generate electrical energy during a deceleration or descent period of a vehicle in which the energy management system is implemented. For example, if the electric motor and a drive unit (e.g., a propeller or drive wheel) are fixedly mechanically coupled, i.e., there is no clutch or similar separating unit, any deceleration or descent of the vehicle will cause electrical energy to be generated.

[0020] Another implementation variant of the energy management system provides at least one light sensor configured to detect the intensity of sunlight incident on the at least one solar panel. Such a light sensor can be provided at any location on the surface of the vehicle and is preferably provided on the surface of the at least one solar panel. Additionally, each of the at least one solar panel can be equipped with a corresponding light sensor. The controller is then configured to control the at least one electrical load based on the detected intensity of sunlight. For example, the controller can be connected to the at least one light sensor to receive a signal and / or digital data representative of the intensity of sunlight incident on the light sensor.

[0021] The energy management system may be further operable such that, particularly during the transition phase of sunlight (i.e., sunset or sunrise), the fuel cell is operated at or above the minimum load of the fuel cell, while excess electrical energy is stored as: fuel produced by an electrolyzer; and / or potential or kinetic energy obtained via an electric motor and a drive unit; and / or electrical energy stored in a battery. Additionally, the excess electrical energy may be used by a heater or a payload, and the heater or the payload carrier is operated at a time when excess electrical energy is available (e.g., under the control of a controller). The transition phase of sunlight typically requires a constant or step adjustment of the power generated by the fuel cell, which corresponds to the electrical energy produced less or more by at least one solar panel. However, the conventional twice-daily change of the output level of the fuel cell results in wear of the fuel cell and severely reduces the lifespan of the fuel cell. Therefore, operating the fuel cell at or above the minimum load according to the first aspect or one of its variants enables the fuel cell used in the vehicle to have a good power-to-weight ratio and increases the lifespan of the fuel cell.

[0022] It should be understood that, for example, in bright sunlight, i.e., when at least one solar panel generates sufficient or more energy for all electrical loads, the fuel cell may be completely turned off.

[0023] According to another variant of the embodiment, the energy management system includes a plurality of fuel cells configured to convert chemical energy into electrical energy. Each of the foregoing variants of the embodiment may be applicable to each of the plurality of fuel cells. For example, if more electrical energy is required, more than one fuel cell will be activated (e.g., under the control of a controller).

[0024] Additionally or alternatively, the (single) fuel cell or one or more of the plurality of fuel cells is a multi-partition fuel cell, wherein each partition of the fuel cell can be independently operated. For example, the effective area in which the reaction gases in the fuel cell can be aggregated together can be divided into fluidly separated parts (partitions). Therefore, reaction gases are supplied only to one or more of these partitions, enabling each partition of the fuel cell to be independently operated.

[0025] The controller can be configured to control each of the plurality of fuel cells and / or each of the partitions of the one or more fuel cells such that: ensuring that a minimum load is applied to each of the plurality of fuel cells and / or each of the fuel cell partitions; and / or, one or more of the plurality of fuel cells and / or fuel cell partitions output a constant power; and / or, the power provided by the plurality of fuel cells and / or one or more of the fuel cell partitions is greater than the minimum power required by the at least one electrical load; and / or, the plurality of fuel cells and / or one or more of the fuel cell partitions operate at optimal efficiency. In other words, the controller can provide the required energy to the electrical bus while only operating the required number of fuel cells and / or the required number of partitions in one or more fuel cells, but operating in the optimal power mode of the fuel cells and / or partitions.

[0026] It should be understood that the controller can further operate one or more fuel cells and / or partitions at different power levels. This allows for the optimal efficiency of each fuel cell and / or partition while enabling the achieved power output to be greater than the minimum required power for all electrical consumers at the electrical bus.

[0027] According to a second exemplary aspect for understanding the present disclosure, an aircraft includes an energy management system according to the first aspect or one of its variations.

[0028] For example, the aircraft can be a high altitude platform station or a high altitude pseudo - satellite. This type of aircraft is used to maintain a flight mode for several days, weeks or even months. Here, it is important that the fuel cells and other components can operate for a long time, that is, have a long lifespan. Therefore, operating the fuel cell at or above the minimum load of the fuel cell or in a constant power mode, and / or providing power from the sub - fuel cells greater than the minimum power required by at least one electrical load and / or operating the fuel cell at optimal efficiency, increases the lifespan of the fuel cell and reduces the risk of failure.

[0029] According to a third exemplary aspect for understanding the present disclosure, a method for managing energy in a system (the system having a fuel cell, at least one energy source and at least one electrical load) includes the steps of: electrically coupling the fuel cell, the at least one energy source and the at least one electrical load through an electrical bus; and controlling the at least one electrical load to ensure that a minimum load is applied to the fuel cell.

[0030] Alternatively or additionally, at least one electrical load is controlled such that the fuel cell outputs a constant electrical power. Alternatively or additionally, at least one electrical load is controlled such that: the electrical power provided by the fuel cell (100) is greater than the minimum electrical power required by the at least one electrical load (130, 140, 150), and / or the fuel cell operates at an optimal efficiency.

[0031] In a variant of the method, the at least one electrical load includes an electrolyzer, and the method includes the steps of: operating the electrolyzer such that: ensuring a minimum load is added to the fuel cell, and / or the fuel cell outputs a constant electrical power, and / or the electrical power provided by the fuel cell is greater than the minimum electrical power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency.

[0032] Alternatively or additionally, the at least one electrical load includes an electric motor mechanically coupled to a propeller, and wherein the method includes the steps of: operating the electric motor such that: ensuring a minimum load is added to the fuel cell, and / or the fuel cell outputs a constant electrical power, and / or the electrical power provided by the fuel cell is greater than the minimum electrical power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency. Optionally, the method may further include: performing a climbing and / or accelerating action by a vehicle including the system.

[0033] According to another variant, the method may further include the step of: operating the electric motor as a generator during a decelerating or descending action of the vehicle.

[0034] According to another variant, the method may further include the steps of: detecting the intensity of (sun) light incident on at least one solar panel by at least one light sensor. Controlling the at least one electrical load then includes: operating the at least one electrical load according to the detected (sun) light intensity.

[0035] The present disclosure is not limited to the various aspects and variants of the forms and sequences described. Specifically, the description of each aspect should not be construed as a specific defined grouping of features. It should be understood that the present disclosure also covers combinations of aspects and variants not explicitly described. Thus, each variant or optional feature may be combined with any other aspect, variant, optional feature or even a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Preferred embodiments of the present invention will be explained in more detail below with reference to the accompanying schematic diagrams.

[0037] Figure 1 An energy management system is schematically shown.

[0038] Figure 2 A flowchart schematically showing a method for managing energy in a vehicle; and

[0039] Figure 3 A schematic illustration of an aircraft according to an embodiment of the present invention. Detailed Description

[0040] Figure 1 A schematic illustration of an energy management system 10 is shown, which includes a fuel cell 100 configured to convert chemical energy into electrical energy. For example, the fuel cell 100 can be operated with reaction gases such as hydrogen and oxygen. The reaction gases can be stored in a fuel tank 101, which can include more than one chamber to facilitate storage of at least two different reaction gases separated from each other. The fuel tank 101 is shown as forming a structural unit with the fuel cell 100. However, the fuel tank 101 can also be separated from the fuel cell 100 and can be connected to the fuel cell 100 through one or more pipes (not shown) for the reaction gases.

[0041] The fuel cell 100 can be configured as a regenerative fuel cell 100, which is constructed such that it can recycle (regenerate) exhaust gases or liquids (such as water). For this purpose, the energy management system 10 further includes an electrolyzer 130, which is configured to convert an ionic substance into fuel (e.g., the reaction gas of the fuel cell 100) by applying direct current (electrical energy) to the ionic substance. The electrolyzer 130 is fluidly connected to the fuel tank 101 through one or more associated pipes 131. Although only one pipe 131 is shown in Figure 1 , it should be understood that multiple pipes 131 can also be used to connect the fuel tank 101 to the electrolyzer 130. In addition, although Figure 1 the electrolyzer 130 is illustrated as a separate component, the electrolyzer 130 can also form a structural unit with the fuel cell 100 and / or the fuel tank 101, so that the pipe 131 can be omitted, or at least made very short.

[0042] The electrical energy generated by the fuel cell 100 is provided to an electrical bus 20 through an associated wire 21. The electrical bus 20 is configured to supply electrical energy to at least one electrical load 130, 140, 150 schematically shown in Figure 1 . The energy management system 10 can further include at least one energy source 110, for example, an electric motor 140, a storage battery 150, and / or a solar panel 110 configured to convert light into electrical energy. The at least one energy source 110 is also electrically connected to the electrical bus 20 through an associated wire 22. Therefore, the electrical bus 20 electrically couples the fuel cell 100, the at least one energy source 110, and the at least one electrical load 130, 140, 150.

[0043] The controller 30 of the energy management system 10 is configured to control at least one electrical load (130, 140, 150) to ensure that a minimum load is added to the fuel cell 100. In other words, the controller 30 controls at least one electrical load (130, 140, 150) such that the power consumed at the electrical bus 20 does not drop below the minimum load of the fuel cell 100. This ensures that the fuel cell 100 can operate in a predetermined power mode, e.g., an optimal and / or high power mode, thereby avoiding wear and tear of the fuel cell 100.

[0044] The controller 30 may further be configured to control at least one electrical load (130, 140, 150) such that the power provided by the fuel cell 100 is constant. In other words, the power consumption of at least one electrical load (130, 140, 150) is controlled in such a way that the fuel cell 100 can operate in a constant mode and generate power in a constant manner. Alternatively or additionally, the controller 30 may also be configured to control at least one electrical load (130, 140, 150) such that the power provided by the fuel cell 100 is greater than the minimum power required by at least one electrical load (130, 140, 150), and / or the fuel cell 100 operates at optimal efficiency.

[0045] For example, the controller 30 may activate or deactivate at least one electrical load (130, 140, 150), or may operate at least one electrical load (130, 140, 150) in a mode where the at least one electrical load (130, 140, 150) consumes a specific amount of power. Based on the electrical energy provided by at least one energy source 110 and / or based on the electrical energy consumed by the remaining electrical loads (130, 140, 150), the controller 30 may activate, deactivate or operate at least one electrical load (130, 140, 150) in a specific energy consumption mode. In this way, the controller 30 can compensate for changes in the electrical energy flowing through the electrical bus 20, such as changes in the electrical energy provided by at least one energy source 110 and / or changes in the electrical energy consumption caused by at least one load (130, 140, 150).

[0046] For example, if the electrical energy available at the electrical bus 20 increases or decreases due to a change, the electrolyzer 130 can increase or decrease its electrical energy consumption, respectively, i.e. can produce more or less reaction gas for the fuel cell 100, respectively. In this way, the electrical energy consumption of the electrolyzer 130 compensates for the change. Therefore, the excess electrical energy available at the electrical bus 20 can be chemically stored. It should be noted that the electrical energy generated by the fuel cell 100 is (at least partially) used to operate the electrolyzer 130. Although this is not common in technology, this can significantly increase the life of the fuel cell 100 due to less wear and tear. For example, if the aircraft 1 including such an energy management system 10 is a high-altitude platform station or a high-altitude pseudo-satellite, it is important that the fuel cell 100 has a long life, because the aircraft 1 may remain in flight mode for days, weeks or even months.

[0047] The energy management system 10 may further include a motor 140, which is one of the at least one electric load 130, 140, 150. The motor 140 is mechanically coupled to a drive unit 141, for example, Figure 1 140 is a vehicle drive wheel or propeller 141 as exemplarily shown in the figure. For example, the drive unit 141 is mounted directly on the output shaft of the motor 140, or is mounted through a gear transmission device (not shown). The controller 30 can operate the motor 140 so that a minimum load is added to the fuel cell 100, and / or the fuel cell 100 outputs a constant amount of power. For example, if the electrical energy available at the electrical bus 20 increases or decreases due to a change, the speed of the motor 140 can be increased and decreased, respectively, so that the power consumption of the motor 140 compensates for the change. When the speed of the motor 140 is increased, the drive unit 141 can also operate faster, and aircraft 1 (such as Figure 3 The vehicle 1 (shown) can perform climbing and / or acceleration actions so that potential energy and / or kinetic energy are stored in the vehicle 1, respectively.

[0048] Likewise, electrical energy may be stored in a battery 150, which is another example of at least one electrical load 130, 140, 150. The controller 30 may be configured to charge the battery 150 in order to store excess electrical energy available at the electrical bus 20. Thus, it is ensured that a minimum load is added to the fuel cell 100, and / or that the fuel cell 100 can output a constant amount of electrical power. Another possible electrical load is an electrical heater of the vehicle 1 (not shown in the drawings in addition to the battery 150), or a commercial load 150 of the vehicle.

[0049] The battery 150 as well as the electric motor 140 may also be used as an energy source, for example, the electric motor 140 may be operated as a generator during deceleration or descent of the vehicle.

[0050] To respond more quickly to variations in the electrical energy generated by at least one energy source 110, in particular at least one solar panel 110, the energy management system 10 may include at least one light sensor 111. The at least one light sensor 111 may detect the intensity of (solar) light incident on the at least one solar panel 110, such that the controller may control at least one electrical load 130, 140, 150 based on the detected intensity.

[0051] Figure 2 A flowchart of a method for managing energy in a system such as an aircraft 1 is schematically shown. The method includes step 200: electrically coupling a fuel cell 100, at least one energy source 110, and at least one electrical load 130, 140, 150 via an electrical bus 20. Thus, the electrical energy generated by the fuel cell 100 and the at least one energy source 110 may be transferred to the at least one electrical load 130, 140, 150. The distribution or allocation of electrical energy to the at least one electrical load 130, 140, 150 may be performed during step 210 of controlling the at least one electrical load 130, 140, 150 such that: ensuring a minimum load is applied to the fuel cell 100, and / or the fuel cell 100 outputs a constant power, and / or the power provided by the fuel cell 100 is greater than the minimum power required by the at least one electrical load 130, 140, 150, and / or the fuel cell 100 operates at an optimal efficiency.

[0052] The control step 210 may be performed according to step 205, i.e., detecting the intensity of (solar) light incident on the at least one solar panel 110. For example, the intensity of (solar) light may be measured via one or more light sensors 111, which are connected to a controller 30, and the controller may control at least one electrical load 130, 140, 150 based on the signals and / or data received from the light sensors 111. Additionally, the control step 210 may be performed according to the usage of another load among the at least one electrical load 130, 140, 150. For example, an electric heater 150 may be used at certain times (e.g., at night or in cold weather conditions), and a payload 150 may also be used at certain times. If the user times of the electric heater 150 and the payload 150 are known in advance, such future electrical energy consumption may be considered in the control step 210.

[0053] The control step 210 for controlling at least one electrical load 130, 140, 150 may include operating the electrolyzer 130 such that: ensuring a minimum load is added to the fuel cell 100, and / or the fuel cell 100 outputs a constant power. Alternatively or additionally, the control step 210 may include operating the electric motor 140 with a propeller 141 such that: ensuring a minimum load is added to the fuel cell 100, and / or the fuel cell 100 outputs a constant power. This may include the climbing and / or accelerating actions of the vehicle 1 performed in step 213. Similarly, the electrolyzer 130 and / or the electric motor 140 may be operated such that: the power provided by the fuel cell 100 is greater than the minimum power required by at least one electrical load 130, 140, 150, and / or the fuel cell (100) operates at an optimal efficiency.

[0054] The electric motor 140 may also be used as an energy source such that the method further includes the decelerating or descending actions of the vehicle 1 performed in step 214, and operating the electric motor 140 as a generator in step 215. Thus, kinetic energy and / or potential energy is converted into electrical energy.

[0055] Figure 3 An aircraft 1 (as a possible vehicle 1) including an energy management system 10 is schematically shown, and the energy management system 10 includes at least one energy source 110. Such an energy source may be at least one solar panel 110 disposed on any surface (outer surface) of the aircraft 1 such that light (sunlight) can be incident on the solar panel 110. Additionally, the aircraft 1 may further include a fuel cell 100 to facilitate providing electrical energy due to a chemical process. For example, when the solar panel 110 does not provide sufficient electrical energy for all consumers (e.g., at night), the fuel cell 100 can generate electrical energy. On the other hand, if at least one solar panel 110 generates sufficient electrical energy, the fuel cell 100 can be completely turned off.

[0056] During the transition phase between night and day (e.g., at sunrise and sunset), the energy management system 10 may control at least one electrical load 130, 140, 150 such that: ensuring a minimum load is added to the fuel cell 100, and / or the fuel cell 100 outputs a constant power, and / or the power provided by the fuel cell 100 is greater than the minimum power required by at least one electrical load 130, 140, 150, and / or the fuel cell 100 operates at an optimal efficiency. Thus, especially during the time when the electrical energy provided by at least one solar panel 110 changes, the fuel cell 100 is not forced to provide a correspondingly changing amount of electrical power.

Claims

1. An energy management system for an aircraft, comprising: - A fuel cell configured to convert chemical energy into electrical energy; - At least one energy source for providing electrical energy; - At least one electrical load; - An electrical bus electrically coupled to the fuel cell, the at least one energy source, and the at least one electrical load; And - A controller configured to control the at least one electrical load such that the power consumed at the electrical bus ensures that a minimum load is applied to the fuel cell, Wherein the at least one electrical load includes an electric motor mechanically coupled to a drive unit; And The controller is further configured to operate the electric motor such that the drive unit performs a climbing and / or accelerating action of the aircraft.

2. The energy management system according to claim 1, wherein, The controller is further configured to control the at least one electrical load such that: The power provided by the fuel cell is constant, and / or The power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or The fuel cell operates at an optimal efficiency.

3. The energy management system according to claim 1 or 2, wherein, The controller is configured to activate or deactivate the at least one electrical load according to the power provided by the at least one energy source; and / or Wherein the energy management system includes a plurality of electrical loads, and the controller is further configured to activate or deactivate a subset of the plurality of electrical loads according to the power consumed by the remaining electrical loads among the plurality of electrical loads.

4. The energy management system according to claim 1 or 2, wherein, The controller is further configured to keep the power provided by the fuel cell constant within a period of time during which the fuel cell operates in a predetermined power mode.

5. The energy management system according to claim 4, wherein, The controller is configured to determine the predetermined power mode and accordingly control the fuel cell.

6. The energy management system according to claim 1 or 2, wherein, The at least one electrical load further includes one or more of the following: - An electrolyzer; - A storage battery; - An electric heater; And - A payload, Wherein the controller is configured to operate each of the at least one electrical load such that: a minimum load is ensured to be applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency.

7. The energy management system according to claim 6, further comprising: - A fuel tank fluidly coupled to the electrolyzer and adapted to store the fuel generated by the electrolyzer and to supply the stored fuel to the fuel cell.

8. The energy management system according to claim 1 or 2, wherein, The at least one energy source includes one or more of the following: - At least one solar panel configured to convert light into electrical energy; - A storage battery; And - An electric motor mechanically coupled to a propeller and configured to operate as a generator during a deceleration or descent period.

9. The energy management system according to claim 1 or 2, further comprising: - A plurality of fuel cells configured to convert chemical energy into electrical energy.

10. The energy management system according to claim 9, wherein, One or more of the plurality of fuel cells are multi-partition fuel cells, wherein each partition of the fuel cell can be operated independently, and Wherein, the controller is configured to control each fuel cell of the plurality of fuel cells and / or each partition of the one or more fuel cell partitions such that: ensuring that a minimum load is applied to each of the plurality of fuel cells and / or each of the fuel cell partitions; and / or, one or more of the plurality of fuel cells and / or the fuel cell partitions output a constant power; and / or, the power provided by the plurality of fuel cells and / or one or more of the fuel cell partitions is greater than the minimum power required by the at least one electrical load; and / or, the plurality of fuel cells and / or one or more of the fuel cell partitions operate at an optimal efficiency.

11. An aircraft, comprising the energy management system according to any one of claims 1 to 10.

12. The aircraft according to claim 11, wherein, The aircraft is a high-altitude platform station or a high-altitude pseudo-satellite.

13. A method for managing energy in a system, the system having a fuel cell, at least one energy source, and at least one electrical load, the at least one electrical load including an electric motor mechanically coupled to a propeller, the system being an aircraft, wherein, The method includes: - electrically coupling the fuel cell, the at least one energy source, and the at least one electrical load through an electrical bus; - controlling the at least one electrical load such that: the power consumed at the electrical bus ensures that a minimum load is applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency; - operating the electric motor such that: the power consumed at the electrical bus ensures that a minimum load is applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the fuel cell operates at an optimal efficiency; and - performing a climb and / or acceleration action by the aircraft.

14. The method according to claim 13, wherein, The at least one electrical load further includes an electrolyzer, and wherein the method further includes: - operating the electrolyzer such that: the power consumed at the electrical bus ensures that a minimum load is applied to the fuel cell, and / or the fuel cell outputs a constant power, and / or the power provided by the fuel cell is greater than the minimum power required by the at least one electrical load, and / or the fuel cell operates at an optimal efficiency.

15. The method according to claim 13 or 14, further comprising: - performing a deceleration or descent action of the aircraft; and - operating the electric motor as a generator during the deceleration or descent action of the aircraft.

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