Lightning protection device, electric propulsion device and aircraft

Abstract

The application provides a lightning protection device, an electric propulsion device and an aircraft, and relates to the field of aircraft technology. The lightning protection device provided by the application comprises a bonding wire, a discharge electrode and at least one lightning receptor, the lightning receptor is used for receiving lightning, the bonding wire is in conductive connection with the lightning receptor; the first end of the discharge electrode is in conductive connection with the bonding wire, the second end is used for extending towards the machine body and has a discharge gap between the machine body; the discharge electrode is configured to receive the lightning current of the bonding wire and conduct the lightning current to the machine body through the discharge gap. By setting the lightning receptor to actively capture the initial lightning and conduct it to the discharge electrode through the bonding wire, since the discharge gap between the discharge electrode and the machine body is an extremely uneven field, it is easy to be broken down by the lightning current to form a conductive path, so that the lightning current is conducted to the machine body by bypassing the core area of the electric motor, thereby improving the protection effect of the electric motor.

Description

Technical Field

[0001] This application relates to aircraft technology, and more particularly to a lightning protection device, an electric propulsion device, and an aircraft. Background Technology

[0002] An electric vertical take-off and landing (eVTOL) aircraft is an aircraft that uses electricity as its power source and has vertical take-off and landing capabilities. It features vertical take-off and landing, intelligent operation, low noise, low emissions, easy maintenance, and high safety. An eVTOL aircraft includes an electric propulsion system, which provides lift or thrust to the aircraft.

[0003] Electric propulsion systems include fairings, propellers, and electric motors. During flight, the fairings and propellers are potential flashpoints, susceptible to lightning strikes that generate currents that affect the stability of the electric propulsion system. Related technologies employ methods such as installing carbon brushes or slip rings between the rotor and stator of the electric motor to act as a lightning grounding path for guiding the current; or installing rolling bearings between the propeller and the electric motor to guide the lightning current from the propeller to the electric motor casing and ultimately to the aircraft frame.

[0004] However, when the current passes through the aforementioned lightning grounding path, it can easily enter the electric motor, thereby affecting its operation and resulting in poor protection. Summary of the Invention

[0005] In view of this, this application provides a lightning protection device, an electric propulsion device, and an aircraft, which can reasonably guide the current generated by lightning on the electric propulsion device and improve the protection effect of the electric motor.

[0006] To achieve the above objectives, this application provides a lightning protection device, an electric propulsion device, and an aircraft, which adopt the following technical solutions:

[0007] In a first aspect, this application provides a lightning protection device, comprising:

[0008] At least one lightning receiving component for receiving lightning, the lightning receiving component being disposed on the propeller blades and / or fairing;

[0009] A bonding wire is used to be installed on the propeller and is electrically connected to the lightning arrester assembly;

[0010] A discharge electrode, wherein a first end of the discharge electrode is electrically connected to the bonding wire; a second end of the discharge electrode is used to extend toward the body, and a discharge gap is formed between the second end of the discharge electrode and the body.

[0011] The discharge electrode is configured to receive the lightning current from the connection wire and conduct the lightning current to the body through the discharge gap.

[0012] In one possible implementation, the lightning protection device provided in this application has a second end of the discharge electrode configured as a cone, with the top end of the cone-shaped second end of the discharge electrode facing the body.

[0013] In one possible implementation, the lightning protection device provided in this application has the lightning arresting component configured to be formed by metallizing the top portion of the blades and / or the fairing; the metallized area is determined by a rolling ball method, and an insulating layer is provided between the metallized area and the blades and / or the fairing, the metallized area being determined by a rolling ball method.

[0014] In one possible implementation, the lightning protection device provided in this application includes a lightning receiving component comprising a lightning receiving part and a current-collecting part electrically connected to the lightning receiving part;

[0015] The lightning arrester is configured with a metallic conductive material, and the metallic conductive material covers the blade and / or the fairing;

[0016] The busbar is configured as a metal strip, which is disposed on one side of the flash receiver and is electrically connected to the junction wire.

[0017] In one possible implementation, the lightning protection device provided in this application includes a first lightning receiving component and a second lightning receiving component;

[0018] The first lightning protection component is disposed on the propeller blade, and the side of the first lightning protection component near the propeller shaft is spaced apart from and insulated from the root of the propeller blade.

[0019] The second lightning arrester is disposed on the fairing, and the side of the second lightning arrester near the fuselage is spaced apart from and insulated from the blade root.

[0020] In one possible implementation, the lightning protection device provided in this application has a lightning-catching portion of the first lightning-catching component extending from the tip of the blade to the root of the blade at a distance greater than or equal to one-half the length of the blade and less than or equal to three-quarters the length of the blade.

[0021] And / or, the distance by which the lightning receiving portion of the second lightning receiving component extends from the top to the bottom of the radome is greater than or equal to one-third of the length of the radome, and less than or equal to one-half the length of the radome.

[0022] In one possible implementation, the lightning protection device provided in this application has an insulating sleeve fitted onto the connection line.

[0023] In one possible implementation, the lightning protection device provided in this application has a discharge gap greater than or equal to 10 mm and less than or equal to 20 mm.

[0024] Secondly, this application provides an electric propulsion device, comprising:

[0025] A propeller includes a fairing, a hub, and multiple blades disposed on the hub, wherein the fairing covers the hub.

[0026] As described above, the lightning protection device is connected to the propeller.

[0027] In one possible implementation, the electric propulsion device provided in this application further includes an electric motor, the electric motor including an outer rotor, the outer rotor being fixedly connected to the hub of the propeller;

[0028] The connection line of the lightning protection device is conformally solidified with the surface of the fairing and / or the outer rotor, and matches the aerodynamic shape of the electric propulsion device.

[0029] And / or, the discharge electrode of the lightning protection device is conformally solidified with the surface of the shroud and / or the outer rotor, matching the aerodynamic shape of the electric propulsion device.

[0030] In one possible implementation, the electric propulsion device provided in this application further includes a pitch control mechanism connected to the root of the blade and the hub.

[0031] The connection between the pitch mechanism and the propeller root, as well as the connection between the pitch mechanism and the propeller hub, are both insulated.

[0032] Thirdly, this application provides an aircraft, comprising:

[0033] The body, the body being externally covered with a skin, the skin being a conductive component;

[0034] Such as the electric propulsion device mentioned above;

[0035] The electric propulsion device is connected to the body.

[0036] In one possible implementation, the aircraft provided in this application has a serrated tip structure on the side of the fuselage facing the discharge electrode.

[0037] The lightning protection device, electric propulsion device, and aircraft provided in this application include a lightning protection device comprising a contact wire, a discharge electrode, and at least one lightning receiving component. The lightning receiving component is used to receive lightning and is disposed on the propeller blades and / or fairing. The contact wire is disposed on the propeller and is electrically connected to the lightning receiving component. A first end of the discharge electrode is electrically connected to the contact wire. A second end of the discharge electrode extends toward the fuselage, and a discharge gap exists between the second end of the discharge electrode and the fuselage. The discharge electrode is configured to receive the lightning current from the contact wire and conduct the lightning current to the fuselage through the discharge gap.

[0038] By setting up a lightning arrestor to actively capture the initial lightning and conduct it to the discharge electrode through a connection wire, the discharge gap between the discharge electrode and the machine body is an extremely non-uniform field, which is easily broken down by the lightning current to form a conductive path. This allows the lightning current to bypass the core area of ​​the electric motor and be conducted to the machine body, thereby improving the protection effect of the electric motor.

[0039] In addition to the technical problems solved by the embodiments of this application, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the technical solutions provided by this application, other technical features contained in the technical solutions, and the beneficial effects brought about by these technical features will be further explained in detail in the specific embodiments. Attached Figure Description

[0040] The specific embodiments of this application are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of this application, and this application is not limited to the specific embodiments described below.

[0041] Figure 1 A schematic diagram of an aircraft provided in an embodiment of this application;

[0042] Figure 2 A partial structural diagram of the lightning protection device and electric propulsion device provided in the embodiments of this application. Figure 1 ;

[0043] Figure 3 A partial structural diagram of the lightning protection device and electric propulsion device provided in the embodiments of this application. Figure 2 ;

[0044] Figure 4 A schematic diagram showing the metallization area determined by the rolling ball method;

[0045] Figure 5 This is a schematic diagram of the structure of the lightning arrester and / or the bonding wire conformally cured with the surface of the propeller, as provided in the embodiments of this application.

[0046] Explanation of reference numerals in the attached figures:

[0047] 11. Airframe; 12. Wing; 13. Tail; 14. Arm; 15. Nacelle; 20. Electric Propulsion System; 20a. Fixed Electric Propulsion System; 20b. Tilting Electric Propulsion System; 22. Propeller; 23. Protective Layer; 100. Electric Motor; 200. Blade; 300. Hub; 400. Pitch Control Mechanism; 500. Skin; 600. Connecting Line; 601. Insulating Sleeve; 700. Discharge Electrode; 800. Lightning Receiving Assembly; 800a. First Lightning Receiving Assembly; 800b. Second Lightning Receiving Assembly; 810. Lightning Receiving Section; 820. Busbar; 900. Fairing.

[0048] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0050] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0051] In the description of the embodiments of this application, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0052] In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise specified precisely.

[0053] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0054] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0055] An electric vertical take-off and landing (eVTOL) aircraft is an aircraft that uses electricity as its power source and has vertical take-off and landing capabilities. It features vertical take-off and landing, intelligent operation, low noise, low emissions, easy maintenance, and high safety. An electric propulsion system is a system that converts electrical energy into mechanical energy to provide lift or thrust to the eVTOL aircraft. Electric propulsion systems include electric motors (also called electric motors), propellers, and related accessories.

[0056] Electric motors have traditionally been used primarily in ground-based industrial products, such as new energy vehicles. Compared to ground-based products, the motors in eVTOL systems must not only meet power requirements but also satisfy various environmental safety flight requirements.

[0057] During flight, the fairing and propeller of an aircraft are potential points of contact for lightning strikes, making them susceptible to generating currents that can affect the stability of the electric propulsion system. Because lightning is an uncontrollable natural phenomenon, and it is often characterized by high voltage and high current, a lightning strike can cause structural damage, destruction, equipment failure, or degradation due to the high voltage and current, potentially leading to catastrophic consequences for the aircraft. Lightning protection is a crucial measure for preventing aircraft from being struck by lightning.

[0058] Because some lightning strikes are difficult to predict, whether an aircraft is flying only in an environment where thunderstorms are not expected or an aircraft that flies in all weather conditions, it is necessary to consider the protection of the aircraft against lightning. For aircraft that fly in all weather conditions, the impact of lightning must be considered even more.

[0059] Compared to traditional propeller-driven aircraft, electric VTOLs (eVTOLs) using electric propulsion systems are more susceptible to lightning damage or destruction after a lightning strike because they rely on electronic and electrical components, especially electric propulsion systems with motors directly driving the propellers. In traditional setups, the electric motor is the inevitable path through which lightning current flows to discharge from the propeller. As the core unit, the electric propulsion system, without lightning protection, may directly fail under high voltage and high current conditions. This could even lead to the formation of a high-voltage, high-current circuit within the aircraft, causing temporary or permanent malfunctions in more electrical equipment and structural failures, resulting in catastrophic consequences for the aircraft when struck by lightning.

[0060] Due to the limited space within the eVTOL aircraft structure, the electromagnetic environment of its electronic equipment during lightning strikes can be significantly harsher. The electric propulsion motor, as the primary power output component, may become a crucial pathway for lightning currents to flow onto the propeller blades, making its electromagnetic environment extremely challenging. The consequences of electric propulsion motor failure are unacceptable and directly impact aircraft safety. Therefore, electric propulsion motors, which handle lightning currents, must be able to withstand such severe electromagnetic environments, necessitating lightning protection measures.

[0061] If an effective current conduction and discharge channel is not built for the propeller blades, and the current on the blades cannot be discharged in time, when the propeller rotates, when the voltage on the blades reaches a certain level, an electric spark discharge will occur at the blade tip or the small gap between the blade hub and the motor. The generated electromagnetic pulse may interfere with airborne communication, navigation, and control systems. Alternatively, due to the motor bearings, the stator and rotor of the motor are electrically isolated, causing the potential difference between the blades and the motor rotor and the motor stator to be conducted to the stator of the electric propulsion motor through the electric propulsion motor bearings. Over time, this may cause electrolytic corrosion of the electric propulsion motor bearings.

[0062] Meanwhile, because the propeller blades fail to establish an effective conduction path with the airframe, the blades will reduce the breakdown voltage between the aircraft and the surrounding air, attracting lightning strikes. The tips of the propeller blades, due to their large curvature and high charge density, may become the preferred path for lightning strikes, increasing the probability of lightning attaching to the blades, which in turn increases the probability that the motor will bear the path of lightning current flow.

[0063] Currently, related technologies employ carbon brushes or slip rings between the rotor and stator of an electric motor to guide current through a lightning grounding path. Carbon brushes are suitable for low linear speeds, environments with ample space, easy maintenance, and convenient collection of carbon brush wear dust. High-current conductive slip rings are also suitable for low-speed environments. However, electric motors in electric propulsion systems operate at higher speeds, have limited space, and the carbon brush wear dust significantly impacts the motor, requiring treatment of the worn carbon dust and frequent maintenance.

[0064] Alternatively, a rolling bearing could be installed between the propeller and the electric motor to add a new lightning grounding path. Therefore, after the lightning current enters the propeller blades, part of the lightning current would be conducted from the rolling bearing to the electric motor housing, while the other part would still enter the motor system through the motor shaft. Current technologies can only disperse a portion of the lightning current entering the propeller blades to the motor housing, but cannot prevent the lightning current from entering the motor system.

[0065] In addition, in the related technologies, the lightning grounding path elements are all installed in contact with the motor housing, and the motor housing is fixedly connected to the machine frame (indicating an internal rotor motor), so that the lightning current can be guided to the machine frame.

[0066] However, for external rotor motors, the motor housing is not fixedly connected to the aircraft frame, meaning that the motor housing and the aircraft frame are in an electrically disconnected state. Electrical connection cannot be achieved through a fixed connection. Due to the high speed and considering wear factors, brushes or carbon brushes cannot be used. If the above setup is still used, lightning current cannot be effectively conducted to the aircraft frame, causing the solution to fail.

[0067] For external rotor motors, the internal electromagnetic environment becomes complex and harsh, and the temperature of the lightning conduction plasma channel is high. The arc heat and large current of the uncertain lightning channel in the small gap may demagnetize the magnets. Due to manufacturing reasons, the lightning conduction path is also uncertain, posing a greater challenge to the protection of external rotor motors. Therefore, the methods currently used are not suitable for the protection of external rotor motors of direct-drive propellers.

[0068] For electromechanical electric motors used in aviation, which contain both high-voltage and low-voltage components, and whose operating conditions and environments are subject to lightning strikes, the technical problem to be solved is how to address the problem of motor structural failure caused by high voltage and high current breakdown of the motor due to lightning, and even temporary or permanent failures and structural failures of other electrical equipment, avoid interference of lightning current on the low-voltage components inside the electric motor, ensure all-weather flight safety, and avoid catastrophic accidents caused by lightning.

[0069] Specifically, regarding lightning protection for all-weather flight external rotor motor direct-drive propeller electric propulsion devices, the lack of lightning protection or inadequate lightning protection may cause direct failure of the motor structure under the high voltage and high current of lightning; it may also cause the high voltage to break down the small gaps in the motor during the lightning current flow, forming a plasma discharge channel, which in turn generates arc heat or Joule heat, causing the magnets in the motor to demagnetize, the windings to burn out, and the electric propulsion device to fail; it may even cause high voltage and high current to enter the internal cross-linking system from the motor end, forming a channel, leading to temporary or permanent failures of more electrical equipment and structural failures.

[0070] Based on the aforementioned technical problems, embodiments of this application provide a lightning protection device, an electric propulsion device, and an aircraft. In this technical solution, the lightning protection device provided by this application includes a contact wire, a discharge electrode, and at least one lightning receiving component. The lightning receiving component is used to receive lightning and is disposed on the propeller blades and / or fairing. The contact wire is disposed on the propeller and is electrically connected to the lightning receiving component. A first end of the discharge electrode is fixed to the propeller and is electrically connected to the contact wire. A second end of the discharge electrode extends towards the fuselage, and a discharge gap exists between the second end of the discharge electrode and the fuselage. The discharge electrode is configured to receive the lightning current from the contact wire and conduct the lightning current to the fuselage through the discharge gap.

[0071] By setting up a lightning arrestor to actively capture the initial lightning and conduct it to the discharge electrode through a connection wire, the discharge gap between the discharge electrode and the machine body is an extremely non-uniform field, which is easily broken down by the lightning current to form a conductive path. This allows the lightning current to bypass the core area of ​​the electric motor and be conducted to the machine body, thereby improving the protection effect of the electric motor.

[0072] The above configuration creates a lightning current conduction path from the lightning arrester to the connection wire, the discharge electrode, and the motor body. This path is far from the electric motor, enabling the conduction of lightning current outside the electric motor. This prevents the current from randomly discharging inside the electric motor, thereby protecting the core components of the electric motor from damage and significantly improving the protection effect.

[0073] It should be noted that, Figures 1 to 5 This diagram illustrates a simplified schematic of the lightning protection device, electric propulsion system, and various components of the aircraft. The specific structures of the lightning protection device, electric propulsion system, and other components of the aircraft are not limited to these details. Figures 1 to 5 of examples.

[0074] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments:

[0075] This application provides an aircraft, which can be an electric vertical take-off and landing (eVTOL) aircraft, or other types of aircraft.

[0076] Figure 1 This is a schematic diagram of an aircraft provided as an embodiment of this application. Wherein, Figure 1 The aircraft shown is for illustrative purposes only and does not constitute a limitation on the specific structure and shape of the aircraft.

[0077] like Figure 1As shown, the aircraft includes a fuselage 11, wings 12, and a tail 13. The fuselage 11 has a symmetrical structure; the remaining structure and shape of the fuselage 11 are not limited and can refer to the structure of the fuselage 11 of existing aircraft. The wings 12 are fixedly connected to the fuselage 11, and the structure of the wings 12 can also refer to the structure of the fixed wings 12 of existing aircraft, which will not be described in detail here. The tail 13 is fixedly located at the tail of the fuselage 11, and the tail 13 is integrally formed with the fuselage 11 or mechanically connected, and has a symmetrical structure. The structure of the tail 13 can also refer to the structure of the tail 13 of existing aircraft, which will not be described in detail here.

[0078] It should be noted that in some scenarios, the aircraft may also include the fuselage 11 and wings 12, that is, the aircraft does not include the tail 13.

[0079] like Figure 1 As shown, the aircraft also includes an electric propulsion unit 20, which can be used to provide power to the aircraft. The number of electric propulsion units 20 can be one or more, for example... Figure 1 As shown, the aircraft includes eight electric propulsion units 20.

[0080] The electric propulsion device 20 is disposed on the fuselage 11 and / or wings 12 and / or tail 13, for example Figure 1 As shown, electric propulsion devices 20 are symmetrically mounted on both the wings 12 and the tail 13. However, in some scenarios, the electric propulsion devices 20 are mounted on the fuselage 11, while those on the wings 12 and tail 13 are not. In other scenarios, the electric propulsion devices 20 are mounted on the wings 12, while those on the fuselage 11 and tail 13 are not. In still other scenarios, the electric propulsion devices 20 are mounted on the tail 13, while those on the fuselage 11 and wings 12 are not.

[0081] See also Figure 1 As shown, the aircraft also includes an arm 14 and a nacelle 15, both of which are used to connect to the electric propulsion unit 20 to mount the electric propulsion unit 20 on the fuselage 11, wing 12, or tail 13. Of course, in some scenarios, the aircraft may also include only one of the arms 14 and the nacelle 15.

[0082] In some embodiments, such as Figure 1 As shown, the electric propulsion device 20 is mounted on the wing 12 via the arm 14. In other embodiments, the electric propulsion device 20 may also be mounted on the wing 12 via a nacelle 15 (not shown in the figure).

[0083] In some embodiments, such as Figure 1As shown, the electric propulsion device 20 is mounted on the tail fin 13 via a nacelle 15. In other embodiments, the electric propulsion device 20 may also be mounted on the tail fin 13 via an arm 14 (not shown in the figure).

[0084] In some examples, the electric propulsion device 20 mounted on the aircraft may include a fixed electric propulsion device 20a, which is fixedly connected to any one of the fuselage 11, wing 12 and tail 13.

[0085] In some examples, the electric propulsion device 20 mounted on the aircraft may include a tilt electric propulsion device 20b, which is provided with a tilting mechanism between the tilt electric propulsion device 20b and any one of the fuselage 11, wing 12 and tail 13, the tilting mechanism being used to adjust the tilt angle of the tilt electric propulsion device 20b.

[0086] In some examples, all electric propulsion devices 20 installed on the aircraft are fixed electric propulsion devices 20a.

[0087] In other examples, all the electric propulsion devices 20 installed on the aircraft are tilt electric propulsion devices 20b.

[0088] In some other examples, the electric propulsion devices 20 installed on the aircraft are partly fixed electric propulsion devices 20a and partly tilting electric propulsion devices 20b, for example... Figure 1 As shown, four of the electric propulsion devices 20 are fixed electric propulsion devices 20a, and the remaining four electric propulsion devices 20 are tilting electric propulsion devices 20b. The fixed electric propulsion devices 20a are located outside the tilting electric propulsion devices 20b.

[0089] like Figure 1 As shown, the electric motor 100 is mounted on the arm 14 or the nacelle 15. The electric motor 100 is connected to the propeller 22 and is used to drive the propeller 22 to rotate to provide power for the aircraft.

[0090] like Figure 2 and Figure 3 As shown in the embodiments of this application, the electric motor 100 can be mounted on the fuselage 11 and / or the wings 12 and / or the tail 13 via a mounting base.

[0091] The propeller 22 can be located on one side of the electric motor 100. The electric motor 100 is connected to the propeller 22 in a transmission manner, and the electric motor 100 is used to drive the propeller 22 to rotate.

[0092] Continue to refer to Figure 2 and Figure 3As shown, in one possible implementation, this application provides a lightning protection device, including a connection wire 600, a discharge electrode 700, and at least one lightning arrester component 800.

[0093] The lightning arrester 800 is used to receive lightning. The lightning arrester 800 is installed on the blades 200 and / or fairing 900 of the propeller 22. Here, only one lightning arrester 800 can be installed on the blades 200 or fairing 900, or multiple lightning arresters 800 can be installed on the fairing 900 and multiple blades 200. The lightning arrester 800 is a metallic conductor and can actively receive lightning.

[0094] The contact wire 600 is used to mount on the propeller 22 and is electrically connected to the lightning arrester assembly 800. It is understood that the propeller 22 provides support and a mounting location for the contact wire 600; for example, the contact wire 600 can be adhered to the surface of the propeller 22, or it can be fixedly embedded within the material coating of the propeller 22. Here, the contact wire 600 can be made of metal to facilitate lightning reception; for example, the contact wire 600 can be iron wire or copper wire.

[0095] The first end of the discharge electrode 700 is used to fix it to the propeller 22 and is electrically connected to the connection line 600; the second end of the discharge electrode 700 is used to extend toward the body 11, and there is a discharge gap between the second end of the discharge electrode 700 and the body 11; the discharge electrode 700 is configured to receive the lightning current from the connection line 600 and conduct the lightning current to the body 11 through the discharge gap.

[0096] In the above embodiment, by setting the lightning receiving component 800 to actively receive the initial lightning, the lightning receiving component 800 can actively receive the lightning current at the positions of the propeller blade 200 and the fairing 900. The current is then conducted to the discharge electrode 700 through the connecting wire 600, and the lightning current converges at the position of the discharge electrode 700.

[0097] The discharge gap between the discharge electrode 700 and the fuselage 11 is a highly non-uniform field, which is easily broken down by lightning current to form a conductive path. This allows the lightning current to bypass the core area of ​​the electric motor 100 and be conducted to the fuselage 11. Finally, the lightning current is discharged to the atmosphere or the ground through structures such as the landing gear, tail fin, and wingtips, thus protecting the electric propulsion device 20. This ensures that the lightning current is conducted only on the surface of the electric propulsion device 20 and the fuselage 11 and does not enter the interior of the electric motor 100.

[0098] Alternatively, it can be understood as ensuring that lightning current is conducted only on the outer surface of the aircraft and does not enter the interior of the electric motor 100, thereby improving the protective effect of the electric motor 100.

[0099] In the above embodiment, the discharge gap can be broken down by a momentary high voltage. Since the voltage in lightning is usually over one million volts and the instantaneous current exceeds one hundred thousand amperes, a strong discharge phenomenon can be generated in the discharge gap. This allows the current on the discharge electrode 700 to be conducted to the body 11.

[0100] In a specific embodiment, the first end of the discharge electrode 700 is fixedly connected to the fairing 900 of the propeller 22. The first end of the discharge electrode 700 may be fixed on the outer surface of the fairing 900 or embedded inside the fairing 900.

[0101] In one possible implementation, refer to Figure 2 As shown, the second end of the discharge electrode 700 is set in a conical shape, and the top of the second end of the conical discharge electrode 700 is directed toward the body 11.

[0102] In the above embodiments, the conical tip possesses inherent electric field distortion characteristics, which can dramatically enhance the electric field strength within a local space, significantly reducing the voltage threshold of the air breakdown discharge gap. When the lightning current is transmitted to the discharge electrode 700 via the bridging wire 600, the conical tip preferentially induces air ionization, forming a stable arc channel; the ionized air becomes a conductive channel, allowing the lightning current to cross the discharge gap and enter the body 11 with minimal loss; the conical tip clearly points towards the body 11, preventing the current from spreading to unintended areas. This constrains the arc within the discharge gap to develop strictly along the axial direction, preventing lateral jumps.

[0103] In one possible implementation, the lightning arrester assembly 800 is configured to form a metallized portion of the top portion of the blade 200 and / or the fairing 900, the metallized area being determined by a rolling ball method, and an insulating layer being provided between the metallized area and the blade 200 and / or the fairing 900.

[0104] In the above embodiments, both the propeller blades 200 and the fairing 900 of the electric propulsion device 20 are potential lightning attachment sites. This embodiment first uses the rolling sphere method to determine the lightning attachment and non-attachment areas of the fairing 900 and the propeller blades 200. The propeller blades 200 and the fairing 900 within the lightning attachment areas are then metallized for lightning interception.

[0105] It should be noted that, due to the requirements of high strength and lightweight design, the blade 200 and fairing 900 are mostly made of carbon fiber composite materials rather than metal materials. Carbon fiber composite materials have a certain degree of conductivity, but the conductivity is poor, and carbon fiber composite materials cannot effectively conduct lightning.

[0106] The internationally standardized rolling sphere method was used to simulate the spatial electric field distribution during the development stage of a lightning leader, quantifying the most vulnerable areas on the aircraft surface. Metallization was applied only to the calculated lightning attachment areas, i.e., the high-probability lightning strike zones, to avoid the weight redundancy caused by full coverage.

[0107] In specific implementation, refer to Figure 4 As shown, for example, using a lightning strike distance of 10 meters (R) for the rolling sphere method, the point of tangency between the rolling sphere and the fairing 900 and the blade 200 is the boundary of the lightning attachment area. The lightning attachment area extends from the top of the fairing 900 or the blade 200 to the point of tangency. The aforementioned lightning attachment area is metallized to enhance its conductivity. The metallization process can be any of the following methods: flame-sprayed metal, application of a metal mesh, or a metal film.

[0108] Furthermore, an insulating layer is provided between the metallized area and the blade 200 and / or fairing 900, so that lightning current can only flow on the surface metal layer of the blade 200 and / or fairing 900 and cannot penetrate into the internal composite material or engine compartment. The insulating layer can be one or more layers of epoxy fiberglass cloth.

[0109] In one possible implementation, refer to Figure 2 and Figure 3 As shown, the lightning arresting assembly 800 includes a lightning arresting part 810 and a current collector 820 electrically connected to the lightning arresting part 810; the lightning arresting part 810 is configured as a conductive metal material, and the conductive metal material covers the blade 200 and / or the fairing 900; the current collector 820 is configured as a metal strip, the metal strip is disposed on one side of the lightning arresting part 810, and the metal strip is electrically connected to the overlap line 600.

[0110] In the above embodiment, a continuous conductive layer is formed by completely covering the critical areas of the blade 200 / fairing 900 with a conductive metallic material (such as copper alloy, aluminum alloy, etc.). By setting a metal strip extending longitudinally along the edge of the lightning arrester 810, the dispersed lightning current is converged to the collector 820 and then connected to the connection cable 600. This combines multiple incident lightning points into a single cable for transmission, reducing the number of interfaces on the connection cable 600 and lowering the risk of poor contact.

[0111] Furthermore, the large cross-sectional area of ​​the metal strip effectively reduces the Joule heating effect, preventing structural deformation caused by instantaneous high temperatures. Specifically, the width of the metal strip is set to 20 mm to 40 mm, and the thickness to 1 mm to 1.5 mm, ensuring that the cross-sectional area of ​​the metal strip is above 20 square millimeters. Ensuring a cross-sectional area above 20 square millimeters guarantees that the metal strip can effectively conduct lightning current.

[0112] In one possible implementation, the lightning protection component 800 includes a first lightning protection component 800a and a second lightning protection component 800b; the first lightning protection component 800a is disposed on the propeller blade 200, and the side of the first lightning protection component 800a near the rotation axis of the propeller 22 is spaced apart from and insulated from the root of the propeller blade 200.

[0113] The second lightning arrester 800b is mounted on the fairing 900. The side of the second lightning arrester 800 near the fuselage 11 is spaced apart from and insulated from the root of the propeller blade 200.

[0114] In the above embodiment, at least two lightning protection components 800 are provided, which can simultaneously protect the propeller blades 200 and the fairing 900 from lightning, further improving the protection effect. In actual applications, the aircraft usually has multiple propeller blades 200, so the number of the first lightning protection components 800a can be adapted to the number of propeller blades 200 to ensure that the fairing 900 and each propeller blade 200 are effectively protected.

[0115] Both the first lightning arrestor 800a and the second lightning arrestor 800b maintain a physical gap from the propeller root and are completely isolated by insulating material. This completely cuts off the traditional intrusion path of lightning current through the propeller blade 200 and propeller root to the electric motor 100, preventing the lightning current from directly reaching the core components of the electric motor 100.

[0116] The aforementioned insulating material can be an insulating material layer coated with modified materials with good insulating properties, such as fiberglass or SiO2 epoxy resin composites, and the thickness of the insulating material layer is set to be more than 2 mm to ensure the insulating performance.

[0117] In one possible implementation, continue to refer to Figure 4 As shown, the distance by which the lightning-catching part 810 of the first lightning-catching component 800a extends inward from the tip of the blade 200 is greater than or equal to half the length of the blade 200 and less than or equal to three-quarters of the length of the blade 200; for example, if the length of the blade 200 is L, then the distance by which the lightning-catching part 810 of the first lightning-catching component 800a extends from the tip of the blade 200 to the root of the blade is 1L / 2-3L / 4. Figure 4 The lightning-catching portion 810 of the first lightning-catching assembly 800a shown extends from the tip of the blade 200 to the bottom by a distance of 3L / 4.

[0118] And / or, the distance by which the lightning-catching portion 810 of the second lightning-catching component 800b extends inward from the top of the rectifier 900 is greater than or equal to one-third of the length of the rectifier 900 and less than or equal to one-half the length of the rectifier 900; for example, if the length of the rectifier 900 is h, then the distance by which the lightning-catching portion 810 of the second lightning-catching component 800b extends from the top of the rectifier 900 to the bottom is 1h / 3-1h / 2. Figure 4The lightning receiving portion 810 of the second lightning receiving component 800b shown extends from the top of the rectifier 900 to the bottom by a distance of 1h / 2.

[0119] In the above embodiments, the above configuration ensures sufficient lightning protection area and avoids the waste of redundant materials.

[0120] In one possible implementation, an insulating sleeve 601 is fitted onto the lap joint 600. Specifically, the diameter of the lap joint 600 is set to 5 mm to 6 mm, specifically any one of 5.0 mm, 5.1 mm, 5.5 mm, and 6 mm. The lap joint 600 and the metal strip can be welded or screwed together to form a stable conductive connection.

[0121] The insulating sleeve 601 covers the outer surface of the connection wire 600. By setting the insulating sleeve 601, the path of current conduction from the connection wire 600 to the propeller 22 is physically blocked, ensuring that the connection wire 600 stably conducts the lightning current to the discharge electrode 700.

[0122] In one possible implementation, the discharge gap is greater than or equal to 10 mm and less than or equal to 20 mm. The discharge gap can be set to any of 10.0 mm, 10.1 mm, 11.0 mm, 15.0 mm, 19.1 mm, and 20.0 mm. The size of the discharge gap directly determines the breakdown voltage threshold of the air dielectric. With the above-described setting, a gap range of 10-20 mm can stably trigger an arc under typical lightning impulse voltages while avoiding self-excited discharge. This ensures rapid air breakdown under lightning peak voltages, forming a stable conductive path.

[0123] Optional, refer to Figure 5 As shown, the bonding line 600 is conformally cured to the surface of the propeller 22 to make the outer surface of the propeller 22 smooth.

[0124] Here, as Figure 5 As shown, in related technologies, the outer surfaces of the propeller blades 200 and fairing 900 of the propeller 22 are coated with a protective layer 23. The bonding wire 600 is embedded within the protective layer 23, or in other words, the bonding wire 600 and the protective layer 23 are pressed together, making the outer surface of the protective layer 23 smooth, thus preventing the bonding wire 600 from protruding and affecting the aerodynamic shape and performance of the electric propulsion device 20. Furthermore, the lightning arrester assembly 800 can also be conformally cured with the surface of the propeller 22 to further avoid affecting aerodynamic performance.

[0125] In one possible implementation, this application also provides an electric propulsion device 20, including a propeller 22 and the aforementioned lightning protection device. The propeller 22 includes a fairing 900, a hub 300, and a plurality of blades 200 disposed on the hub 300. The fairing 900 covers the hub 300. The lightning protection device is connected to the propeller 22. The plurality of blades 200 are evenly disposed around the periphery of the hub 300. A lightning protection component 800 is disposed on the blades 200 and / or the fairing 900 of the propeller 22. Here, the number of lightning protection components 800 is set to multiple, with at least one lightning protection component 800 disposed on the fairing 900 and at least one lightning protection component 800 disposed on each blade 200.

[0126] In this embodiment, a lightning arresting component 800 is provided on the fairing 900, and each propeller blade 200 is also provided with a lightning arresting component 800. A connection line 600 is provided at the bottom end of the fairing 900 of the propeller 22, and each lightning arresting component 800 is electrically connected to the connection line 600. This means that the current collected from each lightning arresting component 800 is guided to the connection line 600, which is electrically connected to the discharge electrode 700. Through the discharge electrode 700, the lightning current is conducted to the fuselage 11 using the discharge gap.

[0127] The electric propulsion device 20 provided in this embodiment further includes an electric motor 100, which includes an outer rotor fixedly connected to a propeller 22. Specifically, the outer rotor of the electric motor 100 is fixedly connected to the hub 300 of the propeller 22. The electric motor 100 also includes an electric motor body, which is mounted on the body 11 and is insulated from the body 11.

[0128] The electric motor drives the rotor hub 300 to rotate via the outer rotor, which in turn drives the blades 200 to rotate, thus achieving power transmission. The bonding line 600 can also be conformally solidified with the surface of the outer rotor to match the aerodynamic shape of the electric propulsion device 20.

[0129] In one possible implementation, the bonding wire 600 can also be conformally solidified with the surface of the fairing 900 to match the aerodynamic shape of the electric propulsion device 20.

[0130] In one possible implementation, the discharge electrode 700 can be connected to either the fairing 900 or the outer rotor. When the discharge electrode 700 is connected to the fairing 900, it conformally cures with the surface of the fairing 900; when the discharge electrode 700 is connected to the outer rotor, it conformally cures with the outer surface of the outer rotor. Of course, when the discharge electrode 700 is simultaneously connected to both the fairing 900 and the outer rotor, it conformally cures with the surfaces of both the fairing 900 and the outer rotor simultaneously.

[0131] In one possible implementation, the portion of the connection line 600 that connects to the blade 200 and / or the blade root of the blade 200 is conformally solidified with the outer surface of the blade 200 and / or the blade root of the blade 200 to match the aerodynamic shape of the electric propulsion device 20.

[0132] In this embodiment, the connection line 600 can also be connected to the fairing 900, and the connection line 600 is conformally cured with the surface of the fairing 900. Of course, the connection line 600 can also be connected to both the fairing 900 and the outer rotor at the same time. In this way, the connection line 600 is conformally cured with both the surface of the fairing 900 and the outer rotor, thereby avoiding affecting the aerodynamic effect of the electric propulsion device 20 or the aircraft.

[0133] In the above embodiment, the lightning current on the propeller blade 200 is guided to the fuselage 11 through the lightning protection device, preventing the lightning current from affecting the electric motor 100 of the electric propulsion device 20. The structure of the lightning protection device has been described above and will not be repeated here. The electric propulsion device 20 equipped with the above-mentioned lightning protection device can reasonably guide the current generated by lightning on the electric propulsion device 20, thereby improving the protection effect.

[0134] Especially for the external rotor electric motor 100, the outer casing of the electric motor 100 is not fixedly connected to the body 11, and the outer casing of the external rotor electric motor 100 is in an electrically disconnected state from the body 11, thus preventing the lightning current from being effectively conducted to the body 11. Using the solution of this application, a discharge gap is set between the discharge electrode 700 of the lightning protection device and the body 11 as the lightning conduction path, guiding the lightning current received by the blades 200 and / or the fairing 900 to the body 11, blocking the lightning current from entering the electric motor 100 system and preventing damage to the external rotor electric motor 100 system.

[0135] Compared to the low resistance requirement of traditional low-voltage electrical conductive paths, the discharge gap here has an infinite resistance. However, when the high voltage of lightning is applied to the discharge electrode 700, the tip of the discharge electrode 700 makes the electric field at the discharge gap extremely non-uniform. The discharge gap can be easily broken down by voltage to form a circuit, thus achieving the purpose of lightning conduction.

[0136] In one possible implementation, such as Figure 3 As shown, the electric propulsion device 20 also includes a pitch mechanism 400, which is connected to the blade root and the blade hub 300 of the blade 200.

[0137] The connection points between the pitch mechanism 400 and the propeller root, as well as the connection points with the propeller hub 300, are insulated. The number of propeller blades 200 driven by the pitch mechanism 400 can be set according to requirements. For example, only some of the propeller blades 200 can be driven to rotate and change the pitch, or all the propeller blades 200 can be driven simultaneously to achieve pitch change. By setting the pitch mechanism 400, the pitch change or tilting function of the propeller 22 can be realized.

[0138] In the above embodiments, the connection between the pitch mechanism 400 and the propeller hub 300 is insulated, such as by using an insulating coating material or an insulating structural component, to prevent lightning from being conducted from the propeller root and the propeller hub 300 to the pitch mechanism 400.

[0139] In one possible implementation, this application provides an aircraft including a fuselage 11 and the aforementioned electric propulsion device 20, wherein the electric motor 100 of the electric propulsion device 20 is located inside the fuselage 11. The structure of the electric propulsion device 20 has been described above and will not be repeated here. The fuselage 11 is externally covered by a skin 500, which is a conductive element.

[0140] By setting a skin 500 on the body 11, the current conducted from the discharge electrode 700 to the body 11 can be further conducted to the skin 500, forming a discharge path to prevent high voltage and high current from damaging sensitive internal components of the motor.

[0141] In one possible implementation, the skin 500 can be a metallic conductive component or a conductive component made of composite materials. For example, the skin 500 can be made of aluminum alloy, a conventional mainstream material, which is lightweight, has moderate strength, low cost, and is easy to process; the skin 500 can also be made of titanium alloy, which has an extremely high strength-to-weight ratio, high temperature resistance (supersonic flight), and corrosion resistance.

[0142] Skin 500 can also be a composite material, such as a skin 500 integrated with composite materials and metal mesh. It features lightweight, high strength, fatigue resistance, and high designability. For example, a skin 500 integrated with carbon fiber reinforced polymer and metal mesh.

[0143] In one possible implementation, the body 11 is provided with a serrated or other pointed structure (not shown in the figure) on the side facing the discharge electrode 700, which strengthens the highly non-uniform electric field between the body 11 and the discharge electrode 700 and promotes the effectiveness of discharge gap discharge.

[0144] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the application disclosed herein.

[0145] The embodiments in this application are intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed in this application. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

[0146] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A lightning protection device, characterized in that, include: At least one lightning receiving component (800) is provided for receiving lightning, the lightning receiving component (800) being provided on the blades (200) and / or fairing (900) of the propeller (22); A connection line (600) is provided on the propeller (22) and is electrically connected to the lightning arrester assembly (800); A discharge electrode (700) is provided, the first end of which is electrically connected to the bonding wire (600); the second end of the discharge electrode (700) is used to extend toward the body (11), and there is a discharge gap between the second end of the discharge electrode (700) and the body (11). The discharge electrode (700) is configured to receive the lightning current from the bridging wire (600) and conduct the lightning current to the body (11) through the discharge gap, and conduct the lightning current on the electric propulsion device and the outer surface of the body; the electric propulsion device includes an electric motor, the electric motor (100) includes an outer rotor, the outer rotor being fixedly connected to the hub (300) of the propeller (22).

2. The lightning protection device according to claim 1, characterized in that, The second end of the discharge electrode (700) is set in a conical shape, and the top end of the conical discharge electrode (700) is directed toward the body (11).

3. The lightning protection device according to claim 1, characterized in that, The lightning arrester assembly (800) is configured to form a metallized top portion of the blade (200) and / or the fairing (900); an insulating layer is provided between the metallized area and the blade (200) and / or the fairing (900), and / or the metallized area is determined by a rolling ball method.

4. The lightning protection device according to claim 1, characterized in that, The lightning arresting component (800) includes a lightning arresting part (810) and a current-collecting part (820) electrically connected to the lightning arresting part (810). The lightning arrester (810) is configured with a metallic conductive material, and the metallic conductive material covers the blade (200) and / or the fairing (900). The busbar (820) is configured as a metal strip, which is disposed on one side of the lightning receiver (810) and is electrically connected to the bridging wire (600).

5. The lightning protection device according to claim 4, characterized in that, The lightning protection component (800) includes a first lightning protection component (800a) and a second lightning protection component (800b); The first lightning protection component (800a) is disposed on the blade (200), and the side of the first lightning protection component (800a) near the rotation axis of the propeller (22) is spaced apart from and insulated from the root of the blade (200); The second lightning arrester (800b) is disposed on the fairing (900), and the second lightning arrester (800b) is spaced apart from and insulated from the blade root of the propeller (200) on the side near the body (11).

6. The lightning protection device according to claim 5, characterized in that, The distance from the tip of the blade (200) to the root of the first lightning receiving component (800a) is greater than or equal to one-half the length of the blade (200) and less than or equal to three-quarters the length of the blade (200). And / or, the distance by which the lightning-catching portion (810) of the second lightning-catching component (800b) extends from the top to the bottom of the rectifier (900) is greater than or equal to one-third of the length of the rectifier (900) and less than or equal to one-half the length of the rectifier (900).

7. The lightning protection device according to any one of claims 1 to 6, characterized in that, An insulating sleeve (601) is fitted onto the lap joint (600).

8. The lightning protection device according to any one of claims 1 to 6, characterized in that, The discharge gap is greater than or equal to 10 mm and less than or equal to 20 mm.

9. An electric propulsion device, characterized in that, include: The propeller (22) includes a fairing (900), a hub (300) and a plurality of blades (200) disposed on the hub (300), wherein the fairing (900) covers the hub (300). The lightning protection device as described in any one of claims 1 to 8, wherein the lightning protection device is connected to the propeller (22).

10. The electric propulsion device according to claim 9, characterized in that, The connection line (600) of the lightning protection device is conformally solidified with the surface of the fairing (900) and / or the outer rotor, and matches the aerodynamic shape of the electric propulsion device (20); And / or, the discharge electrode (700) of the lightning protection device is conformally solidified with the surface of the shroud (900) and / or the outer rotor, matching the aerodynamic shape of the electric propulsion device (20).

11. The electric propulsion device according to claim 9 or 10, characterized in that, It also includes a pitch mechanism (400) connected to the root of the blade (200) and the hub (300). The connection between the pitch mechanism (400) and the propeller root, as well as the connection between the pitch mechanism (400) and the propeller hub (300), are insulated.

12. An aircraft, characterized in that, include: Body (11), the body (11) is covered by an outer skin (500), the skin (500) is a conductive component; The electric propulsion device (20) as described in claim 10 or 11; The electric propulsion device (20) is connected to the body (11).

13. The aircraft according to claim 12, characterized in that, The body (11) has a serrated tip structure on the side facing the discharge electrode (700).

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