Time-varying electrical load balancing in aircraft power distribution networks

Abstract

A power distribution network (306) of the aircraft power system (300) is operated such that it successively employs a plurality of different partial load sharing modes in a time-varying manner, which provides partial load sharing for associated electrical loads (AA, BB, CC, DD) across power sources (A, B, C, D) by successively switching between a plurality of different partial load sharing configurations of the power distribution network, each partial load sharing configuration being associated with a particular one of the partial load sharing modes.

Description

Detailed Description of the Invention

[0001] [Technical Field] The present invention generally relates to a power system for an aircraft, and to an aircraft provided with such a power system. For example, the aircraft may be a canard-type aircraft comprising a plurality of lift / thrust units distributed along a canard or forewing, and along an aft wing or main wing. The power system connects a plurality of electrical loads such as at least one of a plurality of lift / thrust units and a plurality of flap actuators, a plurality of power sources such as a plurality of storage batteries or battery units, and the power sources to the electrical loads A power distribution network configured as described above is provided such that each electrical load can be driven by at least one associated power source via at least one associated power lane of the power distribution network. The present invention further relates to a method for operating an aircraft power system. [Background] Aircraft can generally be classified into fixed-wing type and rotary-wing type. Fixed-wing aircraft typically comprise a plurality of moving blades that guide the movement of the aircraft from one destination to another when controllably positioned. The number and types of moving blades included in an aircraft may vary. Primary control surfaces are generally those used to control the motion of the aircraft about the pitch, yaw, and roll axes. Secondary control surfaces are generally those used to affect the lift and / or drag of the aircraft. Typically, primary control surfaces include elevators, ailerons and rudders, and secondary control surfaces typically include a plurality of flaps, slats, speed brakes, and spoilers.

[0002] Rotary-wing aircraft such as helicopters, for example, generally do not include moving blades separate from the airfoil that generates lift, but the airfoils constituting the rotary wings provide cyclic control for pitch and roll, and collective control for lift.

[0003] Furthermore, aircraft with vertical takeoff and landing capabilities based on propulsion engines are well known, where the propulsion engines are rotatably mounted relative to the aircraft's left-right axis or pitch axis. The propulsion engines are controllably movable between the cruising flight position and the takeoff / landing position. In the cruising position, the engines provide forward thrust, and the aircraft's movement through the air is controlled by appropriate control surfaces. In the takeoff / landing position, the propulsion engines are angled downward to enable vertical takeoff or landing based on the thrust they provide.

[0004] Such aircraft, possessing vertical takeoff and landing capabilities and equipped with electric ducted propellers as propulsion engines, have been proposed by the applicant Lilium eAircraft GmbH in US2016 / 0023754A1 and US2016 / 0311522A1 and further publications of the same patent family. The applicant has also developed an aircraft called the Lilium Jet, which is a canard aircraft equipped with multiple left forward engines, multiple right forward engines, multiple left rear engines, and multiple right rear engines in the form of electric ducted propellers, which are mounted on the left and right canards and the left and right rear wings or main wings, respectively, at the front of the canard aircraft. The first test flight of the Lilium Jet was conducted on October 1, 2019.

[0005] Another type of electrically operated aircraft with vertical takeoff and landing capabilities is known in US2020 / 0010187A1. The aircraft comprises multiple propulsion assemblies, each having two independent windings, thereby making the electric motors dual-supplied. Multiple battery units are associated in pairs with the electric motors, such that the first winding of each electric motor can be driven based on one of the battery units, and the second winding of each electric motor can be driven based on another battery unit. Various power system architectures aimed at achieving fault tolerance are disclosed. According to a first embodiment, six electric motors and six battery units are arranged in a ring architecture such that each battery unit powers two electric motors, and each electric motor receives power from two battery units. According to a second embodiment, six electric motors and four battery units are arranged in a doublet architecture such that each battery unit powers three electric motors, and each electric motor receives power from two battery units. According to the third embodiment, the six electric motors and six battery units are arranged in a hexagram architecture such that each battery unit powers two motors and each electric motor receives power from two battery units. According to the fourth embodiment, the six electric motors and four battery units are arranged in a star architecture such that each battery unit powers three electric motors and each electric motor receives power from two battery units. According to the fifth embodiment, the six electric motors and four battery units are arranged in a star architecture such that each battery unit powers three electric motors and each electric motor receives power from two battery units. According to the sixth embodiment, the six electric motors and four battery units are arranged in a mesh architecture such that each battery unit powers three electric motors and each electric motor receives power from two battery units. According to the mesh architecture, the first set of battery units drives both windings of a commonly associated first electric motor, and the second set of battery units drives both windings of a commonly associated second electric motor.

[0006] For all such types of aircraft, and all other types of aircraft, resilience to mechanical failure is one of the most important aspects, and this is also closely related to the aircraft's power distribution network.

[0007] Power distribution networks for safety-critical applications such as aircraft all face an inherent contradiction: isolation prevents fault propagation, while integration allows for efficient load balancing across power sources. A typical approach includes isolated "power lanes" containing electrical faults in one lane, but does not benefit from load balancing across power sources. Any approach using integration is considered inherently insecure because electrical faults propagate throughout the network, causing temporary or permanent power outages. Therefore, typical power distribution networks for safety-critical applications strictly adhere to isolation and thus miss opportunities to reap the benefits of integration.

[0008] According to conventional approaches, certain integrations may be introduced in response to the occurrence of a failure, in order to compensate for that failure. For example, conventional aircraft electrical systems may use electromechanical relays to bring about integration, but this comes with a reduction in safety tolerances, and thus only leads to the subsequent system failure.

[0009] It is known that solid-state and electromechanical switching devices are used in power distribution networks to enable and disable power transmission between relevant parts of the network, depending on the current situation and needs.

[0010] Furthermore, in the event of a short circuit, it is known that solid-state and electromechanical circuit protection devices (SPDs), such as solid-state and electromechanical circuit breakers, are used in power distribution networks to protect electrical wiring and downstream electrical loads. It is also well known that so-called "solid-state power controllers" or "semiconductor power controllers" are used, and these are commonly referred to as "SSPCs" as circuit protection devices in power distribution networks, including aircraft power distribution networks, and replace conventional electromechanical circuit breakers or even "older" fuses.

[0011] A solid-state power controller (SSPC) is a circuit protection device like a fuse or another type of circuit breaker, and therefore, is intended to protect electrical wiring and downstream electrical loads in the event of a short circuit. Compared to conventional electromechanical devices (fuses and circuit breakers), SSPCs have numerous advantages, including faster opening in the event of a short circuit, being lighter and able to use a smaller volume, being software resettable (no need to manually contact them for maintenance or carry spare fuses), being highly flexible with respect to current and voltage trip ratings, being able to self-test to avoid potential failures, being able to record data regarding the health of the electrical system, and being able to perform further functions, including switching functions. For this purpose, an SSPC includes a microcontroller, a communication interface for data communication with a higher-level control entity, one or more load channels having a monitoring function for monitoring the electrical state of at least one of the load channels, and solid-state switches within each load channel, such as at least one metal-oxide-field-effect transistor (MOSFET), at least one bipolar transistor (BJT), a silicon-controlled rectifier (SCR), and a triac. The microcontroller monitors at least one electrical condition, including the current flowing through each load channel to each load, and instructs a solid-state switch to open when an electrical trip condition occurs, such as when the detected current exceeds a certain threshold. Multiple electrical trip conditions may be set to resolve different types of electrical faults.

[0012] For example, various SSPC distribution architectures are well known, such as hierarchical architectures optimized for centralized control of more SSPCs (e.g., >40 SPPs) from a vehicle management system (VMS) having at least one electrical system controller (ESC). Control is achieved via solid-state power managers (SSPMs), which are grouped together with the associated SSPCs in secondary power distribution units (SPDUs). Similarly, less hierarchical architectures are well known and are typically used for centralized control of a smaller number of SSPCs (e.g., <40 SPPs) from a vehicle management system (VMS). The SSPCs are grouped within primary power distribution units (PPDUs). The SSPC distribution architecture may provide redundancy by having at least two electrical system controllers (ESCs) in the vehicle management system (VMS) and at least two solid-state power managers (SSPMs) in each secondary power distribution unit (SPDU).

[0013] For the power system of an electric aircraft having multiple power sources in the form of batteries or battery units to supply power to various electrical loads or aircraft equipment, unbalanced discharge of these power sources is undesirable and can cause problems. In addition, unbalanced discharge of batteries can adversely affect the range. To achieve high performance of the aircraft, it is preferable that each of the electrical loads or aircraft equipment, such as each of the multiple lift / thrust units, can be driven by multiple independent power sources, at least in certain situations such as flight maneuvers that require increased driving force for the lift / thrust units.

[0014] In consideration of the foregoing, the object of the present invention is to provide a power system for an aircraft and a corresponding operating method that enables sufficient resilience to electrical failures in an efficient manner.

[0015] A further object of the present invention is to provide a power system for an aircraft and a corresponding operating method that enables high aircraft performance with respect to flight control, which also requires increased power as well as a feasible range.

[0016] A further object of the present invention is to provide a power system for an aircraft and a corresponding operating method that enables uniform discharge of a power source in the form of a battery or battery unit. [Overview of the prefecture] To achieve at least one of these objectives, the present invention provides a power system for an aircraft comprising a plurality of electrical loads, a plurality of power sources, and a power distribution network configured to connect the power sources to the electrical loads, such that each electrical load can be driven by at least one associated power source via at least one associated power lane of the power distribution network.

[0017] The power distribution network comprises at least one of a circuit protection device and a circuit switching device having multiple switchable or disconnectable power links, each power link having two connection ports, each power link being configured in a first operating mode to connect the connection ports to transmit power from a driven power lane or driven power lane section connected to one of the connection ports to a driven power lane or driven power lane section connected to the other connection port, and in a second operating mode to disconnect the connection between the connection ports to prevent the transmission of power between the driven power lane or driven power lane section and the driven power lane or driven power lane section.

[0018] The power distribution network is configured to provide partial load balancing with respect to the relevant electrical loads across the power sources in a time-varying manner, according to a number of different partial load balancing modes continuously employed by the power distribution network, by continuously switching between a number of different partial load balancing configurations of the power distribution network, and each partial load balancing configuration is associated with one specific partial load balancing mode.

[0019] The power distribution network is further configured such that each power source in at least one power source group of the plurality of power sources is associated with at least one, preferably at least two, different partial load balancing modes, and each electrical load in at least one electrical load group of the plurality of electrical loads is associated with at least one, preferably at least two, different partial load balancing modes, and each partial load balancing mode has a plurality of associated power sources and electrical loads such that the power sources and electrical loads form one common load balancing group or a plurality of partitioned load balancing groups of the respective partial load balancing mode, and when the power distribution network adopts each partial load balancing mode, it results in load balancing with respect to the electrical loads of the associated common load balancing group, across the power sources of the associated common load balancing group, or results in separate partial load balancing with respect to each of the partitioned load balancing groups, which is load balancing with respect to the electrical loads of each respective partitioned load balancing group, across the power sources of each respective partitioned load balancing group, with no load balancing beyond the partitioned load balancing group.

[0020] The proposed power system makes it possible to combine the main advantages of integrated and isolated electrical networks. Partial load balancing across power sources enables intentional integration between power lanes of the network. In principle, all, or at least most, of the advantages of an integrated power distribution network can be realized without requiring full integration across the network. The proposed partial integration appears to be particularly advantageous for load balancing across power sources such as batteries.

[0021] The power distribution network may be configured to operate in at least one normal operating mode and at least one electrical fault mitigation operating mode. In this regard, it is further proposed that the power distribution network be configured to successively employ different partial load balancing modes in the normal operating mode. Thus, the power distribution network provides the proposed partial load balancing across multiple power sources in the normal operating mode.

[0022] In an electrical fault mitigation mode, the power distribution network preferably provides electrical fault isolation such that a network portion of the power distribution network experiencing an electrical fault is isolated from at least one other network portion of the power distribution network by at least one power link, which is a second operating mode. Together, the proposed power system enables a combination of the advantages of an integrated electrical network and the advantages of a separated electrical network, which also contributes to achieving resilience to electrical faults. In a normal operating mode assumed in the normal flight operation of an aircraft, continuously varying the partial integration between the power lanes of the network enables efficient partial load balancing across power sources. In the event of an electrical fault, the power distribution network assumes an electrical fault mitigation operating mode, which results in isolation between the power lanes involved and, consequently, electrical fault isolation.

[0023] Based on the present invention, a partially integrated electrical network having time-varying partial integration is realized, and although the integrated approach is conventionally considered unsafe for safety-critical applications such as flight, this inherently brings all the advantages of the integrated approach to the normal operation of the aircraft.

[0024] Furthermore, the power system of the present invention is substantially different from conventional power distribution networks for aircraft, which, in the normal operation of an aircraft, have predetermined electrical loads immutably allocated to predetermined power sources through the use of isolated power lanes. This allocation results in uneven power demands on the power sources, which is not ideal, especially for battery-powered electric vehicle / electric aircraft applications. Subsequently, in order to ensure continuity of supply to the electrical load following a power lane failure, the isolation must be interrupted by introducing some degree of integration. This loss of isolation results in a reduction of the safety margin.

[0025] According to the present invention, various approaches are pursued in complexity. Multiple or all power sources and multiple or all electrical loads are partially integrated or connected together in a time-varying manner according to multiple partial load balancing configurations, which is optimal for load balancing across power sources and, together with, for uniform power demand to power sources. By appropriately associating these power sources with partial load balancing configurations, it is possible to achieve uniform discharge of batteries acting as power sources. Any electrical faults are safely isolated before they can propagate, and after the fault has disappeared, the integration may be safely reconfigured, and the network returns to normal operation. By appropriately associating power sources and loads with partial load balancing configurations, even resilience to electrical faults in normal operation can be achieved without relying on immediate fault isolation.

[0026] Compared to a standard integrated network, fault isolation in multiple partial load balancing configurations allows for easier and faster fault elimination in a partially integrated and partially isolated power distribution network, as only a limited number of power sources supply the fault, unlike the numerous power sources that may be present in a standard integrated network. Furthermore, the continuous switching of partial load balancing configurations helps identify which power lane, power source, or load is directly affected by an electrical fault.

[0027] According to a preferred embodiment, partial load balancing across power sources is also advantageous in electrical fault mitigation modes. In this regard, it is proposed that a power distribution network is configured to provide partial load balancing across power sources with respect to the relevant electrical loads in a time-varying manner, according to a plurality of different partial fault isolation load balancing modes continuously employed by the power distribution network, by continuously switching between a plurality of different partial fault isolation load balancing configurations of the power distribution network in electrical fault mitigation modes, each partial fault isolation load balancing configuration being associated with a particular one of the partial fault isolation load balancing modes and providing electrical fault isolation.

[0028] This partial load distribution across power sources may be implemented in an electrical fault mitigation mode similar to partial load distribution across power sources in a normal operation mode by associating power sources and electrical loads in a manner different from that of load distribution modes and load distribution groups. In this regard, the power distribution network is characterized in that each of a plurality or all of the power sources of said at least one power source group, which is not directly affected by an electrical fault, is associated with at least one, preferably at least two, different partial fault-isolated load distribution modes, and each of a plurality or all of the electrical loads of said at least one electrical load group, which is not directly affected by an electrical fault, is associated with at least one, preferably at least two, different partial fault-isolated load distribution modes. It is proposed that each partial fault-isolated load distribution mode has a plurality of associated power sources and a plurality of associated electrical loads such that the power sources and the electrical loads form one common fault-isolated load distribution group or a plurality of split fault-isolated load distribution groups for the respective partial fault-isolated load distribution mode. When the power distribution network employs a respective partial fault-isolated load distribution mode, the power distribution network effects load distribution for the electrical loads of an associated common fault-isolated load distribution group across the power sources of the associated common fault-isolated load distribution group, or effects separate partial load distribution for each of the split fault-isolated load distribution groups, wherein this is load distribution for the electrical loads of each respective split fault-isolated load distribution group across the power sources of that respective split fault-isolated load distribution group, without any load distribution beyond the split fault-isolated load distribution group, and at least one power source, or / and at least one electrical load, is excluded from the load distribution to achieve isolation of the electrical fault.

[0029] Optionally, a plurality of electrical loads of the same type may form an electrical load group. Alternatively, a plurality of electrical loads of different types may form an electrical load group. A plurality of different groups of such types may be provided.

[0030] According to a preferred embodiment, the power distribution network is configured to provide partial load distribution according to a plurality of different partial load distribution modes that are continuously employed for all electrical loads across all power sources.

[0031] There are no restrictions on the architecture and structure of the arrangement of the power distribution network and its power lanes. According to a preferred approach, the power distribution network may comprise a plurality of first-type power lanes, each first-type power lane having at least one associated power source that is not associated with another first-type power lane, and each first-type power lane having at least one associated electrical load that is not associated with another first-type power lane, such that at least one associated power source is or can be connected to at least one associated electrical load via the respective first-type power lane, thereby enabling at least one power source to drive at least one electrical load via the respective first-type power lane without necessarily requiring driving via another first-type power lane. According to the conventional approaches mentioned above, these first-type power lanes will be separated from each other constantly or during normal operation of an aircraft.

[0032] Partial integration between a plurality of first-type power lanes may be achieved by another type of power lane provided in addition to the first-type power lanes. In this regard, it is proposed that the plurality of first-type power lanes are or can be connected via a connection lane arrangement of the power distribution network, wherein the connection lane arrangement comprises one or more second-type power lanes, and is associated with at least one group of first-type power lanes by transmitting power between these first-type power lanes via at least one second-type power lane, or enables partial load distribution for the electrical loads associated with these first-type power lanes across the power sources associated with all first-type power lanes.

[0033] The connection lane device may advantageously include at least one connection lane associated with at least two, preferably at least three, type 1 power lanes, which are connected to or connectable to the connection lane via each type 2 power lane associated with each type 1 power lane.

[0034] The connection lane device may preferably include one or more Type 2 power lanes, each Type 2 power lane having two associated Type 1 power lanes such that two Type 1 power lanes are connected or connectable via a Type 2 power lane, thereby enabling load balancing with respect to electrical loads associated with the two Type 1 power lanes across power sources associated with the two Type 1 power lanes by transmitting power between the two Type 1 power lanes via the Type 2 power lane. In this regard, it is preferable that the transmission of power between two Type 1 power lanes via a Type 2 power lane does not necessarily involve the transmission of power via another Type 2 power lane.

[0035] The first and second type power lanes may be arranged in various different ways or according to various topologies. Generally, when a power distribution network comprises two, three or more second type power lanes associated with a plurality of first type power lanes in such a manner, it would be appropriate that each of the plurality of first type power lanes is connected to or can be connected to at least one other first type power lane via its respective second type power lane.

[0036] In this regard, the first implementation approach further proposes that each of the above-mentioned multiple Type 1 power lanes, or subgroups of the above-mentioned multiple Type 1 power lanes, is connected to or can be connected to two other multiple Type 1 power lanes, or subgroups of the above-mentioned Type 1 power lanes, via its respective Type 2 power lane, thereby enabling partial load balancing across electrical loads in a ring topology.

[0037] According to a second implementation approach, which may be implemented in addition or as an alternative, it is proposed that two power lanes from the plurality of Type I power lanes, or subgroups of the plurality of Type I power lanes, are connected to or connectable to, or to, any other power lane from the plurality of Type I power lanes, or subgroups of the Type I power lanes, via their respective Type II power lanes, and that each of the other power lanes from the plurality of Type I power lanes, or subgroups of the plurality of Type I power lanes, is connected to or connectable to, the two other power lanes from the plurality of Type I power lanes, or subgroups of the Type I power lanes, via their respective Type II power lanes, if one or more such other power lanes are provided, thereby enabling partial load balancing across electrical loads in a linear topology along all of these Type II power lanes. This includes the case where only two Type I power lanes are provided, which are connected to or connectable to each other via Type II power lanes.

[0038] As an alternative to the first and second implementation approaches, or implemented in conjunction with one or both of the first and second implementation approaches, a third implementation approach is proposed to enable partial load balancing across electrical loads in a star topology by having one power lane from the plurality of Type I power lanes, or subgroups of the plurality of Type I power lanes, connected or connectable to at least three other power lanes from the plurality of Type I power lanes, or subgroups of the Type I power lanes, via their respective Type II power lanes. Each of these at least three other power lanes may, if necessary, be a power lane that serves as the starting point for a power lane line containing multiple power lanes, according to the line topology described above.

[0039] According to a preferred variation of the third implementation approach, it is proposed that the connection lanes of a connection lane device are connected to, or can be connected to, at least three power lanes from the plurality of first power lanes, or subgroups of the plurality of first power lanes, via their respective second power lanes, thereby enabling partial load balancing across electrical loads in a star topology. Each of these at least three other power lanes may, in this case as well, be a power lane that serves as the starting point for a power lane line containing multiple power lanes, according to the line topology described above, if necessary.

[0040] A variation of the third implementation approach has the significant advantage that a connecting lane, instead of a Type I power lane, functions as a hub or center in a star topology, thereby making it extremely unlikely that this hub or center will be directly affected by an electrical failure. This hub or center may be isolated by its respective Type II power link from any of the associated Type I power lanes, and together with them, from any electrical failures that may occur therein. This allows for the maintenance of partial load balancing even if an electrical failure directly affecting any one of the Type I power lanes occurs.

[0041] Preferably, each Type 1 power lane is provided with a Type 1 power link, which in its first operating mode allows for the transmission of power from at least one associated power source to at least one associated electrical load via the Type 1 power link, and in its second operating mode prevents the transmission of power from at least one associated power source to at least one associated electrical load via the Type 1 power link.

[0042] Such a Type I power link can essentially correspond to a conventional circuit breaker such as a fuse, or an electromechanical or solid-state circuit protection device, which protects the electrical wiring and downstream electrical load when a short circuit occurs. Therefore, each Type I power link may be configured to change its operating mode from a first operating mode to a second operating mode in response to at least one preset or presetable electrical trip condition indicating an electrical fault.

[0043] A Class I power link may be configured to trip according to one or more predetermined electrical trip conditions. Any suitable electrical trip conditions known in the art may be implemented. This implementation may be carried out in hardware such as conventional fuses and circuit breakers, which have predetermined electrical trip conditions, such as a predetermined set of trip curves implemented by the manufacturer, so that when commanding the device to change the trip curve, the part number of the device would have to be changed.

[0044] For example, at least one predetermined electrical trip condition may include at least one of the following: i) a current transmitted over a first-class power link that exceeds a predetermined current trip threshold; or ii) an amount i2t representing electrical energy wasted over a first-class power link within a predetermined reference time interval that exceeds a predetermined electrical i2t trip threshold.

[0045] In a preferred embodiment, each Type I power link is provided by an electromechanical or solid-state circuit protection device of the power distribution network, such as an electromechanical or solid-state circuit breaker. A solid-state device is preferred. It is not excluded that the Type I power link is implemented by one or more solid-state power controllers (SSPCs) of the power distribution network.

[0046] To enable the power distribution network to assume configurations resulting in partial integration and configurations resulting in partial isolation, a second type of power lane is proposed, each having a second type of power link, which in its first operating mode allows for the transmission of power between first type power lanes via this second type of power link, and in its second operating mode prevents the transmission of power between first type power lanes via this second type of power link.

[0047] For advantages, each Type II power link may be provided by the associated electromechanical or solid-state circuit switching device of the power distribution network. In principle, a fairly simple switching device operating under the control of an appropriate controller may be used. However, if additional or alternative functions other than switching between different partial load balancing configurations are provided, for example, one or more solid-state power controllers (SSPCs) of the power distribution network may provide one or more Type II power links.

[0048] Generally, it is preferable that the power distribution network comprises at least one controller, preferably at least one higher-level controller, which is configured to control the switching of Type II power links between their first and second operating modes, so that the power distribution network can sequentially switch between multiple different partial load balancing configurations or multiple different partial fault isolation load balancing configurations. The controller may also be configured to detect the occurrence of an electrical fault in the power distribution network and to control the network so that it assumes an electrical fault mitigation operating mode.

[0049] To achieve at least one of the above-mentioned objectives, the present invention further provides a method for operating an aircraft power system comprising a plurality of electrical loads, a plurality of power sources, and a power distribution network configured to connect the power sources to the electrical loads, such that each electrical load can be driven by at least one associated power source via at least one associated power lane of the power distribution network. The power distribution network comprises a plurality of switchable or interruptible power links, each located within a respective power lane of the power distribution network, to enable the transmission of power through each power lane in a first operating mode of the power link, and to block the transmission of power through each power lane in a second operating mode of the power link.

[0050] The method involves operating a power distribution network to continuously employ a number of different partial load balancing modes in a time-varying manner, which results in partial load balancing with respect to the relevant electrical loads across the power sources by continuously switching between a number of different partial load balancing configurations of the power distribution network, each partial load balancing configuration being associated with one specific partial load balancing mode.

[0051] Each power source in at least one power source group of the plurality of power sources described above is associated with at least one, preferably at least two, different partial load balancing modes, and each electrical load in at least one electrical load group of the plurality of electrical loads is associated with at least one, preferably at least two, different partial load balancing modes, and each partial load balancing mode has a plurality of associated power sources and electrical loads such that the power sources and electrical loads form one common load balancing group or a plurality of partitioned load balancing groups of the respective partial load balancing mode, and when the power distribution network operates to adopt each partial load balancing mode, it results in load balancing with respect to the electrical loads of the associated common load balancing group across the power sources of the associated common load balancing group, or results in separate partial load balancing for each of the partitioned load balancing groups, which is load balancing with respect to the electrical loads of each respective partitioned load balancing group across the power sources of each respective partitioned load balancing group, with no load balancing beyond the partitioned load balancing group.

[0052] The method of the present invention, as described above with respect to the power system of the present invention, results in combining the advantages of the conventional isolation approach with the advantages of the conventional integration approach by using partial load balancing.

[0053] The method may include operating the power distribution network in at least one normal operating mode, which results in the aforementioned partial load balancing with respect to the relevant electrical loads across the power source by successively switching between several different partial load balancing configurations of the power distribution network. Furthermore, the method may include operating the power distribution network in at least one electrical fault mitigation operating mode, which results in electrical fault isolation such that a network portion of the power distribution network having an electrical fault is isolated from at least one other network portion of the power distribution network by at least one power link, which is a second operating mode.

[0054] Furthermore, the method of the present invention combines the advantages of the conventional isolation approach with the advantages of the conventional integration approach, with respect to the purpose of not compromising safety in the event of a major failure, as described above with respect to the power system of the present invention.

[0055] In this regard, it is further proposed that the method operates the power distribution network in an electrical fault mitigation mode that continuously employs a number of different partial fault isolation load balancing modes in a time-varying manner, which results in partial fault isolation load balancing with respect to the relevant electrical loads across the power source by continuously switching between a number of different partial fault isolation load balancing configurations of the power distribution network, and each partial fault isolation load balancing configuration is associated with a specific one of the partial fault isolation load balancing modes. Of the at least one power source group described above, any multiple or all power sources that are not directly affected by an electrical fault are each associated with at least one, preferably two, different partial fault isolation load balancing modes, and of the at least one electrical load group described above, any multiple or all electrical loads that are not directly affected by an electrical fault are each associated with at least one, preferably at least two, different partial fault isolation load balancing modes, and each partial fault isolation load balancing mode has a plurality of associated power sources and electrical loads such that the power sources and electrical loads form one common load balancing group or a plurality of partitioned load balancing groups of each partial fault isolation load balancing mode, and when the power distribution network operates to adopt each partial load balancing mode, it results in load balancing over the electrical loads of the associated common fault isolation load balancing group across the power sources of the associated common fault isolation load balancing group, or it results in isolated partial load balancing over each of the partitioned fault isolation load balancing groups, which is load balancing over the electrical loads of each respective partitioned fault isolation load balancing group across the power sources of each respective partitioned fault isolation load balancing group, with no load balancing beyond the partitioned fault isolation load balancing group. The method involves operating a power distribution network in an electrical fault mitigation configuration such that at least one power source and / or at least one electrical load is excluded from load balancing in order to achieve electrical fault isolation.

[0056] The power distribution network of a power system may comprise a first-class power lane, each having its own first-class power link. Furthermore, the power distribution network of a power system may comprise one or more second-class power lanes, each having its own second-class power link. Each first-class power lane may enable at least one associated power source to drive at least one associated electrical load without necessarily involving driving through another first-class power lane, by connecting at least one associated power source to at least one associated electrical load. Furthermore, each second-class power lane may be connected to or connectable to at least two associated first-class power lanes, enabling power transmission between first-class power lanes, thereby enabling partial load balancing with respect to the electrical loads associated with these first-class power lanes across the power sources associated with these first-class power lanes.

[0057] According to the present invention, the method includes repeatedly switching a second type of power link between its first and second operating modes, thereby causing a power distribution network to continuously switch between a plurality of different partial load balancing configurations or a plurality of different partial fault isolation load balancing configurations.

[0058] With respect to such a power distribution network, the method may preferably further include changing the operating mode of one or more Type 2 power links from a first operating mode to a second operating mode in order to isolate an electrical fault in an electrical fault mitigation mode.

[0059] In consideration of the foregoing, the present invention provides a method for providing load balancing capability to a power distribution network using multiple battery power sources while avoiding a level of integration that would allow electrical faults to propagate dangerously across the power distribution network. For advantage, multiple network lanes of the network may be allocated to partial load balancing, and a multi-stage switching approach may be implemented to enable safe load balancing while preventing the propagation of electrical faults.

[0060] The present invention further provides a general power system for aircraft, characterized by being configured to operate according to the method of the present invention.

[0061] The power system and method for operating the power system of the present invention may, in principle, be applied to or installed inside any type of aircraft. Therefore, the present invention provides an aircraft equipped with a power system as described above, or a power system configured to operate according to the method of the present invention as described above. The aircraft is preferably at least one of a single-seat aircraft, an aircraft with vertical takeoff and landing capabilities, and a canard aircraft. Furthermore, the aircraft is preferably an electric aircraft, as discussed above.

[0062] In a preferred embodiment, the power system may include at least one group of common-type electrical loads in the form of aircraft equipment having a critical relevance to maintaining the safe operation of the aircraft, and the aircraft equipment is arranged in a number and configuration to ensure resilience to failure, such that various subgroups of aircraft equipment, each having at least two common-type aircraft equipment on one or both of the aircraft's fuselage and / or wings, can fail without compromising the aircraft's flight performance and controllability. The common-type aircraft equipment may be the aircraft's electric lift / thrust units.

[0063] To the advantage of this, the aircraft equipment of a subgroup, or each subgroup, is associated with one specific common power lane in the power distribution network of the power system, and is habitably driven through this common power lane. The aircraft equipment of a subgroup, or each subgroup, is arranged and mounted symmetrically on one or both of the aircraft's fuselage and / or wings, thereby directly or indirectly influencing the common power lane, and ensuring that electrical failures resulting in failure of the aircraft equipment of this subgroup do not impair the aircraft's flight performance and controllability.

[0064] Each specific common power lane in a power distribution network may be a Type 1 power lane, as previously discussed. Partial load balancing across multiple or all subgroups may be enabled by a Type 2 power link, as previously discussed.

[0065] Preferably, each aircraft device is associated with at least one or more different partial load balancing modes so that the aircraft devices form one common load balancing group or multiple partitioned load balancing groups for each of the partial load balancing modes. In this regard, it is further proposed that the aircraft devices are associated with different partial load balancing modes to form the one common load balancing group or each of the multiple partitioned load balancing groups, in such a manner that electrical failures affecting the aircraft devices of each common load balancing group or each of the multiple partitioned load balancing groups directly or indirectly, and causing failure of the aircraft devices, do not impair the flight performance and controllability of the aircraft, and that for each of the different partial load balancing modes, the aircraft devices of the common load balancing group or the multiple partitioned load balancing groups are arranged and provided symmetrically distributed on one or both of the aircraft's fuselage and / or wings.

[0066] According to this proposal, a failure in either a common load balancing group or multiple partitioned load balancing groups, for example, caused by a short circuit in an electrical load or power source, would not impair the aircraft's flight performance and controllability.

[0067] When such an electrical fault is detected, the fault mitigation mode of the aircraft's power distribution network may be activated. Preferably, this fault mitigation mode results in the continuation of partial load balancing in a modified manner, which isolates the electrical fault. For example, a particular load balancing group or partitioned load balancing group affected by the electrical fault may be excluded from further partial load balancing in the electrical fault mitigation mode. More preferably, the electrical load and / or power source that is the source of the electrical fault, or the power lane directly affected by the electrical fault, particularly the first power lane, may be excluded from further partial load balancing in the electrical fault mitigation mode. [Brief explanation of the drawing]

[0068] [Figure 1] A schematic diagram of an aircraft flight control system is shown, comprising a user interface for the pilot, a redundant flight control computer system, and an electronic or optoelectronic bus system connecting aircraft equipment to the flight control computer system, where the aircraft equipment belongs to the aircraft's power system (not shown). [Figure 2] This is a schematic diagram of a canard-wing aircraft of the first modified example, viewed from above. The first modified example may be realized as a single-seat aircraft with VTOL capabilities, and may be equipped with the aircraft equipment according to the present invention and a power system that includes a power source for supplying power to the aircraft equipment. [Figure 3] This is a schematic diagram of a canard-wing aircraft of the second modification, viewed from above. The second modification may be realized as a single-seat aircraft with VTOL capabilities, and may be equipped with the power system according to the present invention. [Figure 4]Two types of lift / thrust units are schematically shown in subfigures 4a) and 4b), respectively: one with three propulsion engines attached to or integrated with the flap, as shown in Figure 4a), and another with one propulsion engine attached to or integrated with the flap, as shown in Figure 4b). [Figure 5] The lift / thrust units in Figure 4, along with their respective aircraft wings, are shown in side views in subfigures 5a), 5b), 5c), and 5d) at four different flap deflection angles relative to the wings. [Figure 6] This provides a schematic overview of a typical aircraft power system. [Figure 7] A schematic diagram of an aircraft power system with a power distribution network illustrating the first conventional approach is shown. [Figure 8] A schematic diagram of an aircraft power system with a power distribution network illustrating the second and third conventional approaches is provided. [Figure 9] Figure 8 schematically illustrates an aircraft power system as an example of a modified approach to the conventional one. [Figure 10] A schematic example of a line topology suitable for a power distribution network in an aircraft power system in which the present invention may be implemented is provided. [Figure 11] Figure 10 provides a schematic example of the first modified version of the network topology. [Figure 12] A second variation of the network topology shown in Figure 10 is schematically illustrated. [Figure 13] A ring topology suitable for a power distribution network in an aircraft power system is schematically illustrated, and the present invention may be carried out based thereon. [Figure 14] A star topology suitable for a power distribution network of an aircraft power system is schematically illustrated, and the present invention may be carried out based thereon. [Figure 15]A star topology suitable for a power distribution network in an aircraft power system is schematically illustrated, which is particularly preferred, and the present invention may be carried out based thereon. [Figure 16] A simplified version of the canard-wing aircraft shown in Figure 2 is schematically represented in subfigure 16a), an undesirable configuration of the aircraft's power system is illustrated in subfigure 16b), and a desirable configuration of the aircraft's power system is illustrated in subfigure 16c). [Modes for carrying out the invention]

[0069] [Detailed explanation] The following describes a “first approach” and a “second approach” for achieving the main advantages of conventional power network integration and conventional power network separation in a suitable and synergistic manner, with only the “second approach” being the approach of the present invention, and therefore the examples given for implementing the “second approach” are exemplary embodiments of the present invention that are not limited to the present invention. The “first approach” and the examples given for implementing the “first approach” are for comparative purposes only and to complete this disclosure.

[0070] Figures 1-5 illustrate non-limiting examples of aircraft, which may be designed to include a power system according to the present invention.

[0071] Figure 1 schematically illustrates and describes an unspecified example of an aircraft flight control system 10. The flight control system comprises a flight control computer system 12, which may be implemented according to conventional concepts, particularly the concept of redundancy. An example is such a conventional triple architecture comprising three redundant flight control computers 12a, 12b, and 12c, the redundant flight control computers may be redundantly connected, on the one hand to a pilot user interface and on the other hand to aircraft elements and equipment controlled based on pilot commands. Examples of conventional redundancy concepts may be referenced in US7,337,044B2, US8,935,015B2, and US8,818,575B2.

[0072] In Figure 1, various components of the aircraft are schematically represented by elements 14-20, which may represent sensors, actuators (such as actuators for controlling the movement of control surfaces like flaps), propulsion engines, etc., and may be controlled and monitored by the flight control computer system 12 via an appropriate control bus system, such as the CAN bus system 22.

[0073] The flight control system 10 further includes a pilot user interface which may include a left side stick device 30a and a right side stick device 30b, the left side stick device comprising a left side stick 32a having a side stick sensor assembly 38a, and the right side stick device comprising a right side stick 32b having a side stick sensor assembly 38a. The flight control computer system 12 may receive control signals from the pilot user interface via electronic or optical coupling links 42a and 42b.

[0074] Figures 2 and 3 show two canard aircraft as non-limiting examples to which the present invention may be applied, and which may also include a flight control system 10 as illustrated in Figure 1. The canard aircraft 200 has a fixed left rear wing or fixed left main wing 202 and a fixed right rear wing or fixed right main wing 204 at the rear of the aircraft fuselage 203, and a fixed left forewing or fixed left canard wing 206 and a fixed right forewing or fixed right canard wing 208 at the front of the aircraft fuselage. Each wing is provided with arrays of multiple flaps 210, 212, 214 and 216. For example, there may be at least six flaps per forewing or canard wing and at least twelve flaps per rearing or main wing.

[0075] The embodiment shown in Figure 2 has two flaps per forewing or canard and four flaps per hindwing or main wing, while the embodiment shown in Figure 3 has six flaps per forewing or canard and twelve flaps per hindwing or main wing.

[0076] The flaps in both embodiments are pivotably or operably mounted to their respective wings and can be pivoted around a pivot axis or actuated by a pivot component, preferably independently of each other for each flap, by their respective electric actuator devices. Each flap can pivot between an upper first operating position and a lower second operating position. Each flap may take a position with minimal or negligible inclination with respect to the longitudinal axis of the aircraft, possibly the upper first operating position, or a position with maximum downward inclination with respect to the longitudinal axis of the aircraft, possibly the lower second operating position. However, if the position with maximum downward inclination coincides with the vertical direction of the flap, the lower second operating position may alternatively be a position beyond the position with maximum downward inclination, such that the flap point is slightly forward.

[0077] Each of these flaps is fitted with at least one propulsion engine in the form of an electric ducted propeller. The ducted propeller is preferably mounted on the upper surface of each flap. Alternatively, the propulsion engine may be integrated with each flap in such a way that the air channels of each propulsion engine, in which each ducted propeller rotates, are located above and aligned with the upper surface of each forewing or hindwing.

[0078] Preferably, the flaps may be in a lower second operating position, or a position corresponding to another operating position between the first and second operating positions in which the ducted propeller provides only downward vertical thrust, giving the aircraft vertical take-off and landing (VTOL) capability. In the upper first operating position, or another operating position between the first and second operating positions in which the flaps extend longitudinally or at the smallest angle with respect to the longitudinal direction of the aircraft, the operating ducted propeller provides the aircraft with maximum forward thrust. The flaps act not only to control the thrust direction of the propulsion engine or propulsion module, but also as control surfaces that influence the movement of the aircraft in the air based on the principles of normal aerodynamics.

[0079] In the embodiment shown in Figure 2, the flaps are provided with a propulsion module that integrates multiple propulsion engines in the form of ducted propellers. For example, such a propulsion module may comprise three such propulsion engines, thereby providing each flap with three propulsion engines in the form of ducted propellers. In this case, the aircraft would have a total of 36 propulsion engines.

[0080] Figure 4a) shows a schematic diagram of such a propulsion module 230, comprising an array of three propulsion engines 232a, 232b, and 232c, which are attached to a flap 234, the flap 234 may be any one of the flaps 210, 212, 214, and 216 shown in Figure 2.

[0081] In the embodiment shown in Figure 3, each flap is equipped with a propulsion engine in the form of a ducted propeller. Therefore, the aircraft is equipped with a total of 36 propulsion engines.

[0082] Figure 4b) schematically shows such a flap 234 together with the propulsion engine 232 attached to it. The flap 234 may be any one of the flaps 210, 212, 214, and 216 in Figure 3.

[0083] Figure 4 schematically shows each flap 234 together with the propulsion module 230 or propulsion engine 232, as viewed from the rear of the aircraft.

[0084] Figure 5 schematically shows side views of each wing 236 and each flap 234 of an aircraft, which may be any one of the wings 202, 204, 206, and 208 of Figures 2 and 3, with each propulsion module 230 or each propulsion engine 232 attached to each flap 234 for different deflection angles of the flap relative to the wing. For example, a minimum or zero deflection angle, as illustrated in Figure 5a), gives the aircraft maximum forward thrust, while a maximum deflection angle or 90-degree deflection angle, as illustrated in Figure 5d), gives the aircraft maximum downward vertical thrust or vertical thrust only to achieve vertical take-off and landing (VTOL) capability. The maximum deflection angle may be greater than 90 degrees, thereby providing thrust in directions having downward and rearward components.

[0085] Intermediate deflection angles of the flaps, as illustrated in Figures 5b) and 5c), provide thrust in a direction having a downward component and a forward component, according to each deflection angle. This deflection angle can preferably be continuously varied between a minimum deflection angle and a maximum deflection angle. A suitable flap actuator or flap actuator device operating between each wing 236 and each flap 234 is schematically shown as element 240 in Figure 5. A suitable pivot joint or pivot joint device pivotably connecting the flap 234 to the wing 236 is schematically shown as element 242 in Figure 5.

[0086] In Figure 3, each lift / thrust unit, which comprises a flap 234, a propulsion engine 232, and a flap actuator or flap actuator device 240 as illustrated in Figures 4b) and 5, has an associated identification number as shown in the insert in Figure 3, and these are associated with the wings and canards. The six flaps or lift / thrust units 214 of the canard 206 are assigned identification numbers 1.1 to 1.6. The six flaps or lift / thrust units 214 of the canard 208 are assigned identification numbers 2.1 to 2.6. The twelve flaps or lift / thrust units 210 of the main wing 202 are assigned identification numbers 3.1 to 3.12. The twelve flaps or lift / thrust units 212 of the main wing 204 are assigned identification numbers 4.1 to 4.12.

[0087] Identification numbers 1.1, 2.1, 3.1, and 4.1 identify the innermost flap or lift / thrust unit adjacent to or near the fuselage 203, respectively; identification numbers 1.6, 2.6, 3.12, and 4.12 identify the outermost flap or lift / thrust unit at the greatest distance from the fuselage 203; and the other flaps or lift / thrust units, and their positions along their respective wings or canards, are identified correspondingly by the insertion of the four identification numbers in Figure 3.

[0088] In both embodiments, the propulsion engines 232 or propulsion modules 230 located on wings 202, 204, 206, and 208, and the flap actuators 240 associated with the flaps 234 of four arrays of flaps 210, 212, 214, and 216, are aircraft equipment such as elements 14, 16, 18, and 20 in Figure 1, which are controlled by a flight control computer system 12.

[0089] According to a preferred embodiment, all of these aircraft equipment are electric aircraft equipment, and they are driven by power supplied by multiple batteries in the aircraft. The aircraft equipment is the electrical load of the aircraft's power system, and the batteries are the power sources of the aircraft's power system. The power system comprises a power distribution network, which is configured to connect power sources to electrical loads such that each electrical load or aircraft equipment can be driven by at least one associated power source or battery via at least one associated power lane of the power distribution network. The present invention relates to a power system and power distribution network for an aircraft, such as the power system and power distribution network referenced, for example, in connection with the exemplary embodiments shown in Figures 1-5.

[0090] Figure 6 schematically illustrates such a power system 300 as provided by the present invention. The power system comprises a plurality of electrical loads, which in the schematic embodiments shown, are four power sources or batteries 302, individually designated as power sources A, B, C, and D, and a plurality of electrical loads, which in the present invention are individually designated as loads AA, BB, CC, DD1, and DD2, and are typically electric aircraft equipment as previously mentioned. The power sources 302 and the electrical loads 304 are connected or can be connected via a power distribution network 306, which is shown symbolically only in Figure 6. Each of the electrical loads may represent a plurality of electrical loads connected in parallel with the power distribution network 306, as illustrated by electrical loads DD1 and DD2, which together form an electrical load DD driven via the power distribution network.

[0091] According to a conventional approach, the power distribution network 306 would have been implemented as a separate network comprising four independent power lanes 308a, 308b, 308c, and 308d, as shown in Figure 7, each power lane connecting one specific power source to one specific electrical load. Each power lane is provided with power links a, b, c, and d of a set of power links 310, which are circuit protection devices, commonly known as "CPDs," that protect downstream wiring and downstream loads of each power lane from damage in the event of a short circuit. For brevity, power links 310 are referred to as "CPDs" below, only in the sense of an example that is not limited thereto. Such CPDs can be readily selected by those skilled in the art to be appropriate for the wiring or power lane to be protected. CPDs with typical tripping time constants, for example, on the order of about 10 ms, may be used to be appropriate for the power lane of the particular power distribution network to be protected and the specific environment.

[0092] The power distribution network is isolated into individual power lanes 308, so that a failure in one power lane cannot affect another power lane. Therefore, the isolated network has a substantial advantage in that it offers a certain degree of fault tolerance. In the example illustrated in Figure 7, an electrical fault on load BB would cause a power outage on power lane 308b until CPDb isolates the electrical fault. Other power lanes remain unaffected.

[0093] A drawback of isolated networks is the inability to distribute the load. If the loads do not consume equivalent power, this will result in uneven demand on the power source, causing the battery to discharge unevenly. This can limit the performance of electric aircraft.

[0094] Any alternative network that utilizes integration rather than separation would be advantageous for load balancing. The corresponding integrated network is schematically illustrated in Figure 8 by the left network section formed by power lanes 308a and 308b together with power sources A and B, electrical loads AA and BB, and CPDa and b. These two power lanes are connected by connecting lane 312, thereby achieving load balancing across power sources A and B for the associated electrical loads AA and BB. However, any electrical fault occurring in one of these power lanes will affect the other power lanes and propagate through the network, causing a power outage for all lanes connected to the lane directly affected by the electrical fault until the fault is isolated.

[0095] Therefore, in the example shown, since connection lane 312 is located downstream of CPDa and b, an electrical fault in load BB would cause a power interruption not only in power lane 308a but also in power lane 308b, making isolation impossible. Only if, as shown in Figure 9, connection lane 312 connects power lanes 308a and 308b upstream of CPDa and b, can an electrical fault assumed in load D be isolated by CPDb so that load AA can subsequently receive power from power sources A and B.

[0096] A simultaneous power outage across the entire power distribution network is generally unacceptable for a secure / critical power distribution network like the one used for aircraft.

[0097] There are three other drawbacks: i) since the electrical fault is supplied from both power sources A and B, more energy will be released; ii) since the electrical fault is supplied from both power sources A and B, the CPD must interrupt at a higher fault current if it is located downstream of connection lane 312; and iii) depending on the capacity of the network's power sources and the response time of the CPD, other CPDs may also be mistakenly isolated, which would lead to a loss of energy supply to load AA as well as load BB, even though load AA is not faulty.

[0098] Figures 8 and 9 illustrate not only integrated networks but also switchable networks, which are a kind of hybrid solution still employed in conventional aerospace technology. Such networks use switches to bring about integration as well as isolation, depending on the situation. According to Figures 8 and 9, power lanes 308c and 308b are connected via a connecting lane 314 which has a power link 316 in the form of a switch SW, and the power link 316 is located downstream of CPDc and d according to Figure 8 and upstream of CPDc and d according to Figure 9.

[0099] Since a fault occurring while switch SW is closed can propagate between power lanes, closing switch SW results in a significant reduction in the safety margin. Therefore, according to conventional aerospace technology, switch SW is closed following a fault only when the system is operating in degraded mode, and thus the benefits of integration are not realized under normal operation. An example of introducing integration to address such a fault is a failure of power source D, thereby preventing load DD or loads DD1 and DD2 from receiving power from source D via power lane 308d in the isolated state of power distribution network 306. By closing power link 316 or switch SW, these loads can receive power from power source C, which then has to drive load CC along with load DD.

[0100] Along with network integration, the main advantages of network isolation can be realized in a preferred synergistic manner according to two alternative approaches proposed herein and referred to as the “First Approach” and the “Second Approach,” as described below based on exemplary, non-limiting network topologies such as those shown in the embodiments in Figures 10-15. In the following description, the following terms are used, namely, power lanes 308 that connect each power source to each electrical load via their respective power links, such as CPDs, i.e., power lanes 308a, 308b, 308c, and 308d in Figure 10, are referred to as “Type I power lanes.” These Type I power lanes comprise one of each of the power links 310 described above, i.e., one of power links a, b, c, and d in the embodiments shown, which are typically realized as CPDs as described. These power links 310 are referred to as “Type I power links.” For brevity, these power links are also referred to below as “CPDs” only in the sense of non-limiting examples.

[0101] According to the embodiment in Figure 10, these first-type power lanes are connected to each other in pairs by connecting lanes 314, i.e., individual power lanes 314a, 314b, and 314c, which respectively comprise power links ab, bc, and cd of a set of power links 316. These connecting lanes 314 or 314a, 314b, and 314c are referred to as "second-type power lanes," and their power links ab, bc, and cd are referred to as "second-type power links." According to Figure 10, these second-type power links 316, individually referred to as ab, bc, and cd, are located on the upstream side of the power link. Depending on the application and approach being implemented, these second-type power links may be CPDs, switches, SSPCs (solid-state power controllers), etc. A preferred embodiment following the two proposed approaches uses either an SSPC or a switch as the second type of power link, and for the sake of brevity below, these second type of power links will be referred to as one or more "SSPC / SW" (where SW stands for switch), in the sense of being an example without limitation.

[0102] Figure 11 shows an alternative configuration, where the Type 2 power lanes or SSPC / SW316 (ab, bc, cd) are located downstream of the Type 1 power links or CPDa, b, c, and d.

[0103] As shown in Figure 12, it is also possible to provide one or more SSPC / SWs upstream of the CPD of the relevant Type 1 power lane, and one or more Type 2 power links downstream of the Type 1 power link of the relevant Type 1 power lane. The Type 2 power lanes 314a and 314b are located upstream of CPDa, b and c together with their SSPC / SWab and bc, and the Type 2 power lane 314c is located downstream of CPDc and d together with its SSPC / SWcd. Since the loads are connected or can be connected via SSPC / SWab, bc and cd which are included in a certain load balancing connection line formed by the Type 2 power lanes 314a, 314b and 314c, the network topologies in Figures 10, 11 and 12 enable load balancing or partial load balancing across power sources A, B, C and D with respect to electrical loads AA, BB, CC and DD in a line topology.

[0104] Even more advantageous is the ring configuration connection of the second type connection lanes to their SSPC / SWs, which enables load balancing or partial load balancing across power sources A, B, C, and D with respect to loads AA, BB, CC, and DD in a ring topology as illustrated in Figure 13. To show that more first type power lanes with CPDs may be provided and included in load balancing or partial load balancing via the load balancing connection ring line formed by the second type power lanes, the connection between first type power lanes 308c and 308d is shown by a dotted line in Figure 13. The possibility that no further first type power lanes are provided, and therefore no second type power lane 314c with SSPC / SWcd is provided, is also shown in Figure 13.

[0105] The ring lane is closed by a second-type power lane 314d equipped with an SSPC / SWad, which connects the first-type power lanes 308a and 308d.

[0106] Another possibility is to connect the first type power lanes in parallel with their SSPC / SWs to form some kind of star topology for load balancing or partial load balancing. Figure 14 shows an example that is not limited to this. Here, the first type power lane 308a is connected to each of the other indicated first type power lanes via each second type power lane, namely, the first type power lane 308b via the second type power lane 314a, the first type power lane 308c via the second type power lane 314e, and the first type power lane via the second type power lane 314f. These second type power lanes each have their own SSPC / SWs, designated ab, ac, and ad.

[0107] The disadvantage of the proposed configuration is that a fault directly affecting the first-class power lane 308a would also affect all other first-class power lanes, and after isolating this fault, load balancing or partial load balancing would no longer be possible.

[0108] Therefore, a load balancing configuration such as a star as shown in Figure 15 is preferred, which uses a separate connection lane 320 as the hub or center of the star configuration, rather than a first-type power lane, which is connected to or can be connected to the first-type power lanes 308a, 308b, 308c, and 308d, respectively, via the second-type power lanes 314g, 314h, 314i, and 314j, each having its own SSPC / SWax, bx, cx, and dx.

[0109] All of these power distribution network configurations or topologies are merely examples and are not limited to them. All of these topologies may be implemented by combinations of the respective network components of the power distribution network, and other topologies known to those skilled in the art may also be implemented, such as such topologies known in US2020 / 0010187A1 and mesh topologies.

[0110] The configuration and operation of the power distribution network will now be described in accordance with the preferred proposed approach described above. [First Approach] According to the first approach described above, an integrated power distribution network 306 for normal operation is provided, which can be switched to an isolated or partially isolated power distribution network in a very fast manner in the event of an electrical failure. For this purpose, a second type of power link 316 is implemented as a very fast operating solid-state switch, or a very fast operating solid-state CPD, or a similar or more preferred solid-state power controller (SSPC), or as a load channel of one or more solid-state power controllers (SSPCs) of the power distribution network.

[0111] These second-type power links, preferably SSPCs, can conduct under normal operation and thus be transparent with respect to load balancing. However, these second-type power links are configured to introduce isolation very quickly, for example, within 10-20 μs, in the event of an electrical fault being detected. Hereinafter, these second-type power links will be referred to as "SSPCs" only as an example without limitation. Generally, it is preferable that isolation times of about 100 μs, more preferably less than 100 μs, and most preferably about 10-20 μs be achieved by SSPCs. However, longer isolation times of, for example, on the order of 1 ms are not excluded.

[0112] A SSPC is a well-known electronic device comprising one or more conductive channels or load channels, current measuring means for each load channel, and logic means implemented in software or hardware to allow the load channels to be turned off if a certain current threshold is exceeded, or optionally in response to one or more other trip conditions. Such current thresholds and trip conditions can be readily selected or determined by a person skilled in the art based on the design of the power distribution network, and the characteristics of the power sources and electrical loads, and therefore the maximum current values ​​and other electrical conditions expected in normal, fault-free operation. A person skilled in the art will take appropriate safety margins into consideration.

[0113] This results in a power distribution network that, on the one hand, leverages integration to benefit from load balancing, while on the other hand, is fault-tolerant and secure.

[0114] For example, consider the first type power lanes 308a and 308b with power sources A and B, electrical loads AA and BB, CPDa and b, and the second type power lane 314a with SSPCab shown in Figures 10 and 11. SSPCab is inserted in parallel between power lanes 308a and 308b. In the normal operating state of the network, this SSPC is in a conductive state, allowing load AA to be supplied equally by sources A and B, and load BB to also be supplied equally by sources A and B. The same applies to the other first type power lanes and other second type power lanes with their SSPCs shown in Figures 10 and 11, as well as all corresponding power lanes shown in Figures 12-15. This enables load balancing in the normal operation of the power distribution network, while isolating potential electrical faults in a very fast manner by introducing appropriate isolation.

[0115] Preferably, fault isolation is achieved according to a plurality of subsequent fault isolation stages, preferably three isolation stages. This is because the electrical fault that occurs may result in more SSPCs switching from their conducting state to their non-conducting state than is necessary for fault isolation.

[0116] The first and second fault isolation stages can be described and illustrated again, for example, based on Figures 10 and 11, with their associated first type power lanes 308a and 308b having power sources A and B, electrical loads AA and BB, CPDa and b respectively, and associated second type power lane 314a having SSPCab.

[0117] The first fault isolation stage brings this network section to a first type of power lane. If an electrical fault occurs at load BB, SSPCab will then detect an increase in current from power source A supplying the fault and will be isolated very quickly by switching to a non-conducting state. Here, the fault is isolated to power lane 308b, and power lane 308a can continue normal operation. Load AA receives little to no power interruption.

[0118] Here, the electrical fault only affects power lane 308b, and thus fault isolation in this lane can be achieved by the second fault isolation stage. Since the electrical fault only affects power lane 308b of type 1, the urgency of fault isolation is reduced. Since the electrical fault is supplied with electrical energy only from power source B, less energy is released in the fault, and CPDb can safely interrupt the fault current. CPDb can safely isolate faults in the form of anticipated short circuits.

[0119] A key advantage of the proposed approach is that the traditional concept of "selectivity" for coordinating multiple CPDs sequentially between the power source and load, in order to isolate the CPDs in the correct order, is irrelevant or not utilized.

[0120] Except that a Type II power link, preferably an SSPC, should be fast enough to allow each SSPC to trip before a Type I power link or Type I power lane's CPD can trip, one or more SSPCs may be of any speed and do not require coordination with other SSPCs and CPDs. Providing a very fast Type II power link is also advantageous in limiting the duration of each power interruption. Since a Type II power link or SSPC only separates Type I power lanes from each other, rather than isolating its own power from the load, coordination of a Type II power link or SSPC is less critical than coordination of a specific CPD on the network using a prior art approach.

[0121] The third fault isolation stage brings about the recovery of network integration, except for maintaining a certain level of isolation required to isolate electrical faults.

[0122] This fault isolation stage is suitable for larger networks with more power lanes, as can be seen in relation to power sources A and B and loads AA and BB shown in Figures 10-15.

[0123] In such an expanded power distribution network 306, a large number of Type II power links are likely to switch to their deconductive state during the first isolation phase. This is especially true for SSPCs due to their high sensitivity. As a result, load balancing may be lost even between healthy Type I power lanes.

[0124] For example, in network 306 in Figures 10 and 11, it is possible that power lane 308b, not power lane 308c, is affected by an electrical fault, but the SSPCcd between power lanes 308c and 308d switches to a non-conducting state. In order to isolate this electrical fault, only SSPCab and bc must switch to a non-conducting state, and therefore, as soon as SSPCbc switches to a non-conducting state, power lane 308c is isolated from the faulty power lane 308b, SSPCcd can switch back to a conducting state or be switched back.

[0125] In the network topology of Figure 10, assuming that an electrical short circuit occurs in the electrical load BB, even the other SSPCab and bc may return to their conducting state after the fault isolation in the first type of power lane 308b, which follows the second fault isolation stage, i.e., the switching of the CPDb of this power lane to its non-conducting state to interrupt the fault current.

[0126] It is considered preferable to have a Type 2 power lane with a Type 2 power link or SSPC upstream of a Type 1 power link or CPD, given the possibility of faults occurring in the electrical load. In such a case, all power sources may continue to contribute to power supply and load balancing after the recovery of integration by the third fault isolation stage.

[0127] It is preferable to have a Type 2 power lane with a Type 2 power link or SSPC downstream of a Type 1 power link or CPD, considering the possibility of power source failure. In such a case, all electrical loads can continue to be supplied with power based on load balancing across the remaining power sources after the integration is restored by the third fault isolation stage.

[0128] Since both of these possibilities have their own advantages, a mixed configuration, such as the one illustrated in Figure 12, may be used.

[0129] However, it is not excluded that a Type 2 power lane, each equipped with a Type 2 power link, may be provided not only downstream of a Type 1 power link but also upstream. Furthermore, the proposed first approach can be combined with a conventional hybrid approach, namely, a high-speed Type 2 power link, particularly an SSPC, may be provided on one of the upstream or downstream sides, while a conventional switch SW or power link 314, as shown in Figures 8 and 9, which is normally disconnected and selectively switched to a conductive state during a third fault isolation phase, may be provided on the other of the upstream or downstream sides.

[0130] The third fault isolation stage may be performed independently by individual SSPCs under the control of their respective logic means based on the measured electrical state of their load channels. Alternatively, a central controller of the power distribution network may control the SSPCs to perform the third fault isolation stage, for example, based on state data from the CPD and SSPCs, and optionally the measured electrical state of the network.

[0131] The above description of the three fault isolation stages applies similarly to other network topologies in Figures 10-15. After achieving the second fault isolation stage, all SSPCs between all Type I power lanes except the faulty Type I power lane may be reset to a conduction state to reintroduce load balancing and return the network to a near-normal operating state. Due to the achieved fault isolation, this operating state of the network may be referred to as the network's electrical fault mitigation operating mode. Depending on the location of the SSPCs downstream or upstream of the CPD, it may even be possible for all SSPCs to be reset to a conduction state, as one or more CPDs performing fault isolation in each of the relevant Type I power lanes may be sufficient for fault isolation.

[0132] For aircraft, as referenced in relation to Figures 1-5, employing multiple power sources and distributed electric thrust units (EPUs) or lift / thrust units as electrical loads, and generally for so-called eVTOL applications, it is advantageous to arrange the EPUs in power lanes symmetrically with respect to the aircraft geometry so as to minimize the impact of power lane losses on the vehicle's controllability. This can be achieved by ensuring that a single power lane supplies a well-distributed set of EPUs rather than adjacent ones, in the case of a network configuration such as the single first-class power lane described above.

[0133] Figure 16 shows a simplified schematic version of an aircraft according to Figures 2 and 3, which has only six EPUs, i.e., EPU1 and EPU2 on the forewing or canard wing, and EPU3, EPU4, EPU5 and EPU6 on the rear wing, in addition to Figure 16a. Each of these EPUs may represent a unit with multiple propulsion engines.

[0134] Figure 16b schematically shows the allocation, which is undesirable because a failure on one power lane affects adjacent EPUs and affects EPUs that are asymmetrical with respect to the axis of symmetry, which is the vehicle's roll axis. Either EPU1, 3, 4 or EPU2, 5, 6 will be affected, with EPU1, 3, and 4 located on the front and rear wings of the right side of the vehicle, and EPU3 and 4 located adjacent to each other on the right rear wing, and EPU2, 5, and 6 located on the front and rear wings of the left side of the vehicle, and EPU5 and 6 located adjacent to each other on the left rear wing.

[0135] Figure 16c schematically illustrates the allocation, which is desirable because a failure on one type 1 power lane does not affect adjacent EPUs and results in better symmetry of the failed EPU (with respect to the axis of symmetry, which is the vehicle's roll axis). Even if one of the power lanes 308a and 308b fails, only one of the two EPUs 1 and 2 on the left and right front wings will be affected, and only one individual EPU on the left and right rear wings, namely EPUs 4 and 5, or EPUs 3 and 6, will be affected.

[0136] The concepts described with reference to Figures 16 and 16c may be similarly applied to the EPU or lift / thrust unit or propulsion engine and flight actuators of the illustrated embodiments in Figures 2 and 3.

[0137] Generally speaking, those skilled in the art can provide a sufficient number of common types of aircraft equipment, in particular lift / thrust units, and can arrange these aircraft equipment in appropriate configurations on aircraft, especially on their wings, and can assign these aircraft equipment in appropriate manner to power lanes, in particular to first-class power lanes of power distribution networks, thereby achieving the desired resilience against single or even multiple electrical failures.

[0138] For example, with respect to Figure 3, an electrical failure could result in the simultaneous failure of lift / thrust units 3.1 and 3.6 on the left wing 202 and / or lift / thrust units 4.1 and 4.6 on the right wing 204. Along with this, one or two lift / thrust units adjacent to the fuselage, and one or two lift / thrust units still quite close to the fuselage would be affected, resulting in little to no effect on the lateral balance.

[0139] For example, with respect to Figure 3, an electrical failure could result in the simultaneous failure of the outermost lift / thrust unit 1.6 of the left canard 206 and the outermost lift / thrust unit 4.12 of the right main wing 204, and / or the outermost lift / thrust unit 2.6 of the right canard 208 and the outermost lift / thrust unit 3.12 of the left main wing 202. In this case as well, the lateral balance would remain unaffected or only slightly affected.

[0140] The explained principles for achieving resilience to failures based on the proposed approach can, of course, be applied to other types of aircraft other than those shown in Figures 2, 3 and 16a), and to entirely different types of aircraft, such as those equipped with numerous lift / thrust units, propulsion engines, flaps, etc., where not all of these aircraft engines are necessarily required to maintain the aircraft's flight capability and controllability. To achieve resilience to single, double, or multiple electrical failures, those skilled in the art, when implementing the present invention, can assign various aircraft engines to separate power lanes of a power distribution network in such a manner, thereby minimizing the impact of such single, double, or multiple bus failures. [Second Approach] According to the second approach described above, a power distribution network 306 is provided that is partially integrated and partially isolated for normal operation of the power distribution network, and preferably also for fault mitigation operation modes. According to this approach, the network switches sequentially between a plurality of different partial load balancing configurations associated with each of a plurality of partial load balancing modes. The power distribution network continuously assumes these partial load balancing modes and their respective partial load balancing configurations in a time-varying manner. Each of these different partial load balancing configurations corresponds to a different type of partial integration and partial isolation of the network. Uniform discharge of the power source can be achieved by this sequential, preferably periodic, switching between the partial load balancing configurations.

[0141] The switching between these different partial load balancing configurations is performed by a Type II power link 316, which switches synchronously between its conducting and non-conducting states, preferably relatively slow compared to the tripping times of typical circuit protection devices or CPDs, and even slower compared to the typical tripping times of solid-state power controllers (SSPCs). For example, a suitable time scale for switching the Type II power link 316 might be a one-minute time interval between conducting and non-conducting states. Therefore, although other components could be used to enable switching between conducting and non-conducting states, slower electromechanical or solid-state switches are more suitable for implementing the Type II power link 316.

[0142] In the following, these Type II power links will be referred to simply as one or more “SWs” only, as an example without limitation, to represent one or more suitable switches.

[0143] Furthermore, as in the case of the proposed first approach described above, the first type of power link may be a suitable circuit protection device, i.e., a "CPD". Hereafter, these first type of power links will be referred to simply as one or more "CPDs", in this case as well, only as an example without limitation.

[0144] An example of partial load balancing, delivered across power sources with respect to the relevant electrical load in a time-varying manner, according to a series of different partial load balancing modes continuously employed by the power distribution network, can be given based on the ring topology of Figure 13. Here, it is assumed that the first type power lane 308c and the first type power lane 308d are directly connected by the second type power lane 314c, which has a switch SW as the second type power link cd. Correspondingly, the other second type power links ad, ab, and bc are also switches, while power links a, b, c, and d are CPDs.

[0145] Appropriate partial load balancing modes, designated as stages 1 and 2, are as follows:

[0146] [Table 1]

[0147] By periodically alternating between stages 1 and 2 during operation, it is ensured that an electrical fault never affects more than half of the lanes. According to the two stages 1 and 2, each stage associates the associated power sources A, B, C, and D, along with the corresponding electrical loads AA, BB, CC, and DD, with multiple partitioned load balancing groups, namely, partitioned partial load balancing groups (A+B, AA+BB) and partitioned partial load balancing groups (C+D, CC+DD) in stage 1, and partitioned partial load balancing groups (B+C, BB+CC) and partitioned partial load balancing groups (A+D, AA+DD) in stage 2. These groups in each stage are referred to as "partitioned groups" because the groups do not have any common elements.

[0148] All power sources have the opportunity to integrate with other power sources for load balancing, either directly or through other power sources, if provided.

[0149] This solution is scalable to any number of power lanes.

[0150] For example, other assignments to various stages of power sources and loads are also possible, as shown below.

[0151] [Table 2]

[0152] In this embodiment, each stage assigned the power source and load to a respective partial common load balancing group, namely, a common load balancing group (A+B, AA+BB) in stage 1, a common load balancing group (B+C, BB+CC) in stage 2, a common load balancing group (C+D, CC+DD) in stage 3, and a common load balancing group (A+D, AA+DD) in stage 4.

[0153] However, no particular advantage over the first embodiment will be realized.

[0154] If network criticality allows for a loss of more than half of the lanes at a given point in time, then an additional stage becomes possible where three Type 1 power lanes simultaneously participate in load balancing, for example, as follows:

[0155] [Table 3]

[0156] In this embodiment, each stage reassigned the power source and load to their respective partial common load balancing groups: a common load balancing group (A+B+C, AA+BB+CC) in stage 1, a common load balancing group (B+C+D, BB+CC+DD) in stage 2, a common load balancing group (A+C+D, AA+CC+DD) in stage 3, and a common load balancing group (A+B+D, AA+BB+DD) in stage 4.

[0157] In the event of an electrical failure, each Type 1 power lane will be excluded from further partial load balancing to isolate the electrical failure. Partial load balancing by multiple different partial load balancing modes sequentially employed by the network may still continue.

[0158] If power source C or load CC has an electrical fault, the following steps may be periodically employed by the network:

[0159] [Table 4]

[0160] These stages 1' and 2', which correspond to stages 1 and 4 of the second embodiment described above, correspond to a partial fault isolation load balancing mode for a power distribution network. These stages are part of stages 1 to 4 of the second embodiment described above, with stage 1' corresponding to stage 1 and stage 1' corresponding to stage 4.

[0161] Alternatively, when an electrical fault must be isolated, the electrical fault mitigation mode of the power distribution network may implement permanent load balancing across healthy Type 1 power sources with respect to those loads. In this embodiment, if power source C or load CC also has an electrical fault, the following fault mitigation steps that may be employed by the network permanently employ fault isolation until the electrical fault is resolved.

[0162] [Table 5]

[0163] Another embodiment is given based on the star topology shown in Figure 15. In this case as well, the power links ax, bx, cx, and dx between the connection lane 320, which acts as the central node, and each of the first type power lanes are assumed to be switches. Appropriate embodiments of partial load balancing modes or stages are stages 1 to 6 below.

[0164] [Table 6]

[0165] As in other embodiments, this solution is scalable to any number of power lanes, and the stages can be transitioned in any order. If network criticality allows for losses of more than half of the lanes, then an additional stage becomes possible, where, for example, three lanes instead of just two participate in the simultaneous partial load balancing.

[0166] When power lane 308c fails due to a failure of power source C or load CC, the following steps may be periodically performed in the network's electrical fault mitigation mode.

[0167] [Table 7]

[0168] These steps 1', 2', and 3' are part of steps 1-6 of an embodiment given for normal operation, where step 1' corresponds to step 1, step 2' corresponds to step 3, and step 3' corresponds to step 5.

[0169] Alternatively, if necessary, in the electrical fault mitigation mode of the power distribution network, permanent load balancing across healthy Class I power lane power sources may also be implemented with respect to those loads.

[0170] The transition between the various stages of each implementation or between partial load balancing modes is preferably performed by first opening the currently closed switches and then closing the switching that will be closed to realize the next stage. This ensures that the stage transition does not involve any reduction in the safety margin. Therefore, it is preferable that the switching between stages is not performed directly, but only after intermediate stages without partial load balancing across the power source.

[0171] As will be discussed and explained with reference to Figures 16 and 3, in order to achieve resilience and controllability of the vehicle, critical loads can be appropriately distributed and symmetrically positioned on the first power lane and the wings and fuselage of the aircraft. This also applies in relation to the proposed second approach.

[0172] To the advantage of this, various partial common load balancing groups or partitioned partial load balancing groups in a partial load balancing mode or stage may be provided to be formed in such manner, so that each critical load or aircraft equipment of each respective common load balancing group or partitioned load balancing group is well distributed symmetrically on the aircraft's wings and / or fuselage, so that a failure in one of these groups is not fatal and does not impair the aircraft's controllability. In such a case, it is not so important for the power distribution network to detect and react to the occurrence of an electrical fault very quickly in order to isolate the electrical fault and assume an electrical fault mitigation operation mode.

[0173] There are many possibilities as to how a person skilled in the art may implement the proposed concepts and approaches of this disclosure in detail. A person skilled in the art may also decide to implement both proposed approaches in an aircraft power distribution network by, for example, applying one of these approaches with respect to one network section and the other approach with respect to another network section. Furthermore, a power distribution network may, in principle, be configured according to both approaches, provided that a Type II power link is appropriately selected.

[0174] The terms used above, such as “power source,” “electrical load,” “power lane,” “Type 1 power lane,” “Type 2 power lane,” “power link,” “Type 1 power link,” and “Type 2 power link,” are essentially general terms describing any function in any technical context without necessarily implying any specific structure or element used to achieve these functions. For this reason, multiple power links can be incorporated into each of a single power network device. One or more Type 1 power links, and even one or more Type 2 power links, can be incorporated into each of a single power network device. Such power links incorporated into a power network device may share connection ports of the power network device, for example, such that one connection port of the power network device is simultaneously a connection port for both a Type 1 power link and a Type 2 power link. Such a power network device may also, in this sense, include power lanes or power lane sections that are incorporated into the device along with each power link.

[0175] The power distribution network (306) of the aircraft's power system (300) is operated to continuously employ a number of different partial load balancing modes in a time-varying manner, which results in partial load balancing with respect to the associated electrical loads (AA, BB, CC, DD) across power sources (A, B, C, D) by continuously switching between a number of different partial load balancing configurations of the power distribution network, and each partial load balancing configuration is associated with one specific partial load balancing mode. [Explanation of symbols]

[0176] 10…Flight control system, 12…Flight control computer system, 12a,12b,12c…Flight control computer, 14,16,18,20…Aircraft equipment, 22…Control bus system, 30a,30b…Left and right side stick devices, 32a,32b…Left and right side sticks, 38a,38b…Sensor assembly, 42a,42b…Connecting link, 200…Canard aircraft, 202…Left rear wing, 203 …fuselage, 204…right rear wing, 206…left forewing, 208…right forewing, 210,212,214,216;234…flaps, 230…propulsion module, 232,232a,232b,232c…propulsion engines, 3.1~3.12…lift / thrust unit for left rear wing, 4.1~4.12…lift / thrust unit for right rear wing, 1.1~1.6…lift / thrust unit for left forewing, 2.1~2.6…lift / thrust unit for right forewing, 2 36…wing, 240…flap actuator, 242…pivot coupling, 300…power system, 302;A,B,C,D…power source, 304;AA,BB,CC,DD1,DD2,DD…electrical load, 306…power distribution network, 308;308a,308b,308c,308d…power lane, first-class power lane, 310;a,b,c,d…first-class power link, 312,314…power lane, 316;S W…Power link; switch; 314; 314a, 314b, 314c, 314d, 314e, 314f, 314g, 314h, 314i, 314j…Type 2 power lane; 316; ab, bc, cd, ad, ac, ad, ax, bx, cx, dx, 312, 314, 314a…Type 2 power link; 320…Connection lane; EPU1, EPU2, EPU3, EPU4, EPU5, EPU6…Electric thrust unit

Claims

1. A power system for an aircraft comprising a plurality of electrical loads, a plurality of power sources, and a power distribution network configured to connect the power sources to the electrical loads, wherein each electrical load can be driven by at least one associated power source via at least one associated power lane of the power distribution network, The power distribution network includes at least one of a circuit protection device and a circuit switching device, each having multiple switchable or disconnectable power links. Each power link has two connection ports, and each power link is configured to connect the connection ports in a first operating mode to transmit power from a driven power lane or driven power lane section connected to one of the connection ports to a driven power lane or driven power lane section connected to the other connection port, and to disconnect the connection between the connection ports in a second operating mode to prevent the transmission of power between the driven power lane or driven power lane section and the driven power lane or driven power lane section. Said power distribution network switches continuously between a plurality of different partial load distribution configurations of said power distribution network, so as to, in accordance with a plurality of different partial load distribution modes continuously adopted by said power distribution network, in a time-varying manner, supply power from power sources (A, B; C, D; B, C; A, D; A, B; A, C; A, D; B, C; The configuration is configured to provide partial load balancing with respect to the relevant electrical loads (AA, BB; CC, DD; BB, CC; AA, DD; AA, BB; AA, CC; AA, DD; BB, CC; BB, DD; CC, DD) across B, D; C, D), and each partial load balancing configuration is associated with one of the particular partial load balancing modes. The power distribution network is configured such that each power source in at least one power source group of the plurality of power sources is associated with at least one different partial load balancing mode, and each electrical load in at least one electrical load group of the plurality of electrical loads is associated with at least one different partial load balancing mode, and each partial load balancing mode has a plurality of associated power sources and electrical loads such that the power sources and electrical loads form one common load balancing group or a plurality of partitioned load balancing groups of the respective partial load balancing mode, and when the power distribution network adopts each of the partial load balancing modes, it provides load balancing across the power sources in the associated common load balancing group with respect to the electrical loads in the associated common load balancing group, or provides separated partial load balancing for each of the partitioned load balancing groups, which is load balancing across the power sources in each respective partitioned load balancing group with respect to the electrical loads in each respective partitioned load balancing group, with no load balancing beyond the partitioned load balancing group. Power system.

2. A power system according to claim 1, wherein the power distribution network is configured to operate in at least one normal operating mode and at least one electrical fault mitigation operating mode, and the power distribution network is configured to sequentially employ different partial load balancing modes in the normal operating mode.

3. A power system according to claim 2, wherein the power distribution network provides electrical fault isolation such that, in the at least one electrical fault mitigation operating mode, a network portion of the power distribution network having an electrical fault is isolated from at least one other network portion of the power distribution network by at least one power link, which is the second operating mode.

4. A power system according to claim 1, wherein the power distribution network is configured to provide partial load balancing across all power sources (A, B, C, D) and with respect to all electrical loads (AA, BB, CC, DD) according to a plurality of different partial load balancing modes that are successively employed.

5. A power system according to claim 1, wherein the power distribution network comprises a plurality of first-class power lanes, A power system in which each of the first type power lanes is associated with at least one associated power source (A; B; C; D) that is not associated with another first type power lane, and each of the first type power lanes is associated with at least one electrical load (AA; BB; CC; DD) that is not associated with another first type power lane, so that at least one associated power source is connected to or can be connected to at least one associated electrical load via each of the first type power lanes, and so that at least one power source can drive at least one electrical load via each of the first type power lanes without necessarily involving driving via another first type power lane.

6. A power system according to claim 5, wherein a plurality of the first type power lanes are connected or connectable via a connection lane device of the power distribution network, the connection lane device includes one or more second type power lanes, and transmits power between the first type power lanes via at least one of the second type power lanes, thereby enabling partial load balancing with respect to electrical loads (AA, BB, CC, DD) associated with the first type power lanes across power sources (A, B, C, D) associated with at least one group of the first type power lanes or all of the first type power lanes.

7. A power system according to claim 5, wherein each of the first type of power lanes comprises a first type of power link, which in a first operating mode enables the transmission of power from at least one associated power source (A; B; C; D) to at least one associated electrical load (AA; BB; CC; DD) via the first type of power link, and in a second operating mode prevents the transmission of power from at least one associated power source to at least one associated electrical load via the first type of power link, and each of the first type of power links is configured to change its operating mode from the first operating mode to the second operating mode in response to at least one preset or presetable electrical trip condition indicating an electrical fault.

8. A power system according to claim 6, wherein each of the second type of power lanes comprises a second type of power link, which in a first operating mode enables the transmission of power between the first type of power lanes via the second type of power link, and which in a second operating mode prevents the transmission of power between the first type of power lanes via the second type of power link, and each of the second type of power links is provided by an associated electromechanical or solid-state circuit switching device of the power distribution network.

9. A method for operating an aircraft power system comprising a plurality of electrical loads, a plurality of power sources, and a power distribution network configured to connect the power sources to the electrical loads, wherein each electrical load can be driven by at least one associated power source via at least one associated power lane of the power distribution network, the power distribution network comprising a plurality of switchable or interruptible power links, each provided within each power lane of the power distribution network to enable the transmission of power through each of the power lanes in a first operating mode of the power link, and to block the transmission of power through each of the power lanes in a second operating mode of the power link. The method includes operating the power distribution network to continuously employ a plurality of different partial load balancing modes in a time-varying manner, which involves continuously switching between a plurality of different partial load balancing configurations of the power distribution network, thereby controlling the power sources (A, B; C, D; B, C; A, D; A, B; A, C; A, D; B, C; This results in partial load balancing with respect to the relevant electrical loads (AA, BB; CC, DD; BB, CC; AA, DD; AA, BB; AA, CC; AA, DD; BB, CC; BB, DD; CC, DD) across B, D; C, D), and each partial load balancing configuration is associated with one of the particular partial load balancing modes. Each power source in at least one power source group of the plurality of power sources is associated with at least one different partial load balancing mode, and each electrical load in at least one electrical load group of the plurality of electrical loads is associated with at least one different partial load balancing mode, and each partial load balancing mode has a plurality of associated power sources and electrical loads such that the power sources and electrical loads form one common load balancing group or a plurality of partitioned load balancing groups of the respective partial load balancing mode, and when the power distribution network operates to adopt each of the partial load balancing modes, it results in load balancing with respect to the electrical loads of the associated common load balancing group across the power sources of the associated common load balancing group, or separate partial load balancing for each of the partitioned load balancing groups, which is load balancing with respect to the electrical loads of each of the partitioned load balancing groups across the power sources of each of the partitioned load balancing groups, with no load balancing beyond the partitioned load balancing group. method.

10. A method according to claim 9, the method comprising operating the power distribution network in at least one normal operating mode, which results in the partial load balancing with respect to the relevant electrical loads across the power source by successively switching between a plurality of different partial load balancing configurations of the power distribution network. The method comprises operating the power distribution network in at least one electrical fault mitigation operating mode, which results in electrical fault isolation such that a network portion of the power distribution network having an electrical fault is isolated from at least one other network portion of the power distribution network by at least one power link, which is the second operating mode.

11. The method according to claim 9, wherein each power distribution network comprises a first type power lane having its respective first type power link, and each power distribution network comprises one or more second type power lanes having their respective second type power links. Each of the aforementioned first-type power lanes enables at least one associated power source to drive at least one associated electrical load without necessarily involving driving through another of the aforementioned first-type power lanes, by connecting at least one associated power source to at least one associated electrical load. Each of the aforementioned second power lanes is connected to or connectable to at least two associated first power lanes, thereby enabling the transmission of power between the first power lanes and achieving partial load balancing with respect to the electrical loads (AA, BB, CC, DD) associated with the power sources (A, B, C, D) associated with these first power lanes. The method includes repeatedly switching the second type of power links between their first and second operating modes so that the power distribution network sequentially switches between a plurality of different partial load balancing configurations or a plurality of different partial fault isolation load balancing configurations.

12. An aircraft comprising the power system described in claim 1, wherein the aircraft is at least one of a single-seat aircraft, an aircraft having vertical takeoff and landing capabilities, and a canard-type aircraft.

13. An aircraft according to claim 12, wherein the power system comprises at least one group of common types of electrical loads in the form of aircraft equipment having a significant relevance to maintaining the safe operation of the aircraft, and the aircraft equipment is arranged in a number and configuration to achieve resilience to failure such that various subgroups of the aircraft equipment, each having at least two common types of the aircraft equipment, can fail without compromising the flight performance and controllability of the aircraft.

14. An aircraft according to claim 13, wherein the aircraft equipment of the subgroup, or each of the subgroups, is associated with one particular common power lane of the power distribution network of the power system and is commonly driveable through this common power lane, and the aircraft equipment of the subgroup, or each of the subgroups, is provided symmetrically distributed on one or both of the fuselage and / or wings of the aircraft so as to directly or indirectly affect the common power lane, and an electrical failure causing failure of the aircraft equipment of the subgroup does not impair the flight performance and controllability of the aircraft.

15. An aircraft according to claim 13, wherein each of the aircraft equipment is associated with at least one or more different partial load balancing modes, so that the aircraft equipment forms one common load balancing group or a plurality of partitioned load balancing groups of each of the partial load balancing modes. An aircraft in which the aircraft equipment is associated with different partial load balancing modes to form one of the common load balancing groups or multiple of the partial load balancing groups, in such a manner that an electrical failure directly or indirectly affects the aircraft equipment of each of the common load balancing groups or each of the partitioned load balancing groups, causing failure of the aircraft equipment, and such failure does not impair the flight performance and controllability of the aircraft, and for each of the different partial load balancing modes, the aircraft equipment of the common load balancing group or each of the multiple partitioned load balancing groups is provided arranged symmetrically on one or both of the fuselage and wings of the aircraft.

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