Aircraft electric propulsion system and wing distributed electric propeller propulsion aircraft

Abstract

The embodiment of the specification discloses an aircraft electric propulsion system, the system comprises a power generation subsystem, a power distribution subsystem and a propulsion subsystem, the power generation subsystem comprises a turboshaft engine and a generator; the turboshaft engine is arranged at the tail part of the aircraft and is used for driving the generator to generate electricity; wherein a fan of the turboshaft engine is used for sucking low-speed air of a fuselage boundary layer into the turboshaft engine; the power distribution subsystem is used for distributing power to the propulsion subsystem, and the propulsion subsystem drives an aircraft; wherein the electric power comprises electric power from a power generation subsystem.

Description

Technical Field

[0001] This application relates to the fields of aerodynamic layout design and power architecture technology for aircraft, and in particular to electric propulsion systems for aircraft and wing-mounted distributed electric propeller-driven aircraft. Background Technology

[0002] While providing a fast and convenient mode of travel, air transport also brings serious pollution problems. To address this challenge, the aviation industry has conducted extensive research on technological innovation and proposed various emission reduction solutions. The integrated design of the aircraft fuselage and engine is an advanced aerodynamic optimization design technology and one method to improve fuel efficiency. Currently, combined with the development of hybrid-electric aircraft and electric propulsion technologies, boundary layer intake (BLI) and distributed propulsion (DP) technologies are important ways to improve the overall propulsion efficiency of the aircraft.

[0003] BLI technology can improve propulsion efficiency, reduce contrail and velocity losses, and lower propulsion power consumption for the same thrust. It can also optimize airflow configuration across the entire aircraft, realizing potential aerodynamic benefits. Furthermore, distributed propulsion can increase the effective bypass ratio of the entire aircraft, thereby improving overall propulsion efficiency.

[0004] In existing technologies, propulsion systems typically include two turbofan engines mounted under the wings, with a portion of their shaft power used to drive generators. The propulsion system also incorporates boundary layer intake technology, directing a portion of the slower-moving boundary layer air from the fuselage and / or wing to electrically driven ducted fans at the tail of the fuselage and / or wing. This re-excites the boundary layer airflow downstream of the aircraft, reducing drag and improving overall aircraft efficiency. The ducted fan typically orbits the fuselage axis once to maximize overall aircraft efficiency. A portion of the turbofan engine's shaft power (i.e., a portion of the turbine-electric propulsion system) generates electricity to power the electric propulsion system, while the remaining shaft power provides thrust to the engine's bypass fan in a conventional manner. However, due to the uneven velocity distribution of the slower-moving boundary layer airflow entering the turbofan engine, this causes distortion in the inlet airflow of the ducted fan. Utility Model Content

[0005] This specification provides an electric propulsion system for an aircraft and a wing-mounted distributed electric propeller propulsion aircraft to solve the technical problem of how to improve the propulsion efficiency of an aircraft.

[0006] This specification provides an embodiment of an aircraft electric propulsion system, which includes a power generation subsystem, a power distribution subsystem, and a propulsion subsystem. The power generation subsystem includes a turboshaft engine and a generator.

[0007] The turboshaft engine is located at the tail of the aircraft and is used to drive the generator to generate electricity; wherein, the fan of the turboshaft engine is used to draw low-speed air from the fuselage boundary layer into the turboshaft engine;

[0008] The power distribution subsystem is used to distribute power to the propulsion subsystem, which drives the aircraft; wherein the power includes power from the power generation subsystem.

[0009] Optionally, there are two turboshaft engines, which are respectively installed on both sides of the tail of the aircraft, and each turboshaft engine drives a generator.

[0010] Optionally, the power generation subsystem further includes a rectifier, which is used to convert the alternating current generated by the generator into high-voltage direct current, and the power from the power generation subsystem is the high-voltage direct current.

[0011] Optionally, the system further includes a frequency converter for converting DC power from the power distribution subsystem into AC power and supplying the converted AC power to the propulsion subsystem.

[0012] Optionally, the system further includes an energy storage subsystem, and the power includes power from the energy storage subsystem.

[0013] Optionally, the energy storage subsystem includes a lithium battery pack; wherein the power generation subsystem is used to provide steady-state power, and the lithium battery is used to provide / absorb transient power;

[0014] or,

[0015] The energy storage subsystem includes a lithium battery pack. When the state of charge (SOC) of the lithium battery reaches a preset condition, the power generation subsystem supplies power to the lithium battery.

[0016] Optionally, the power distribution subsystem includes a power management system, which is used to distribute power according to a power distribution strategy.

[0017] Optionally, the propulsion device includes a motor and a propeller; the motor is used to convert electrical energy into mechanical energy, drive the propeller to rotate, and provide thrust for the aircraft.

[0018] This specification provides an embodiment of a wing-distributed electric propeller-driven aircraft, the aircraft including any of the above-described aircraft electric propulsion systems.

[0019] Optionally, the aircraft also includes a thermal management system for managing the aircraft's heat dissipation and / or air conditioning system, the thermal management system drawing power from the power generation subsystem.

[0020] The above-described at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0021] The power architecture scheme that utilizes the turboshaft engine at the tail of the fuselage to extract electrical energy involves installing the turboshaft engine at the tail of the aircraft and using the boundary layer airflow at the tail of the fuselage to draw in the low-speed air from the boundary layer of the fuselage into the turboshaft engine. This can effectively improve the working efficiency of the turboshaft engine, thereby improving the power generation efficiency of the power generation subsystem and the propulsion efficiency of the aircraft. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the description of the embodiments of this specification or the prior art will be briefly described below. Obviously, the drawings used in some embodiments of this application are only described below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the high-pressure shaft power extraction of the engine in the first embodiment of this specification.

[0024] Figure 2 A schematic diagram of the component layout of the electric propulsion system in the first embodiment of this specification.

[0025] Figure 3 This is a schematic diagram of the turboshaft engine installation and aerodynamic layout in the first embodiment of this specification.

[0026] Figure 4 This is a schematic diagram of the energy flow of the electric propulsion system in the first embodiment of this specification.

[0027] Figure 5 This is a schematic diagram of the architecture of the electric propulsion system in the first embodiment of this specification.

[0028] Figure 6 This is a schematic diagram illustrating the information interaction relationship between the power management system and other components in the first embodiment of this specification.

[0029] In the diagram: 1. Turboshaft engine; 2. Generator set; 3. Rectifier; 4. Switchboard; 5. Frequency converter; 6. Motor; 7. Electric propulsion propeller; 8. Lithium battery pack; 9. Thermal management system (TMS); 10. Cable; 11. Wingtip propeller. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments involved in the specific implementation are only a part of the embodiments of this application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the specific implementation without creative effort should fall within the protection scope of this application.

[0031] The first embodiment of this specification (hereinafter referred to as "Embodiment 1") provides an electric propulsion system for an aircraft that can provide thrust to the aircraft.

[0032] The electric propulsion system for an aircraft provided in Example 1 includes a power generation subsystem (or power generation system), a power distribution subsystem, and a propulsion subsystem (or propulsion motor system). The power generation subsystem includes a turboshaft engine and a generator.

[0033] The turboshaft engine is located at the tail of the aircraft and is used to drive the generator to generate electricity; wherein, the fan of the turboshaft engine is used to draw low-speed air from the fuselage boundary layer into the turboshaft engine.

[0034] The power distribution subsystem is used to distribute power to the propulsion subsystem, which drives the aircraft; wherein the power includes power from the power generation subsystem.

[0035] Preferably, there are two turboshaft engines, each mounted on either side of the tail section of the aircraft. Each turboshaft engine converts the chemical energy of aviation kerosene into mechanical energy. A generator serves as the power source for the aircraft, with each turboshaft engine driving one generator. The generator can be a built-in rotor generator, and its type can be a permanent magnet synchronous generator.

[0036] Taking an aircraft as an example, a pair of high-pressure turboshaft engines can be installed on both sides of the tail section of the aircraft fuselage. Specifically, the turboshaft engines can be mounted to the fuselage using a structural support system, preferably with the engines partially embedded within the fuselage. According to the principle of BLI technology, drag is reduced and the propulsion efficiency of the turboshaft engine is improved by re-exciting the boundary layer airflow near the fuselage. Therefore, the embedded installation parameters of the turboshaft engine are related to the local boundary layer conditions. Preferably, the length of the engine blades protruding outside the fuselage is 90% of the local boundary layer thickness. The formula for estimating the local boundary layer thickness is:

[0037]

[0038] Where δ is the boundary layer thickness, x is the distance from the engine fan inlet to the engine nose, and Re x=ρVx / μ is the characteristic Reynolds number, where ρ is the air density, V is the flight speed, and μ is the air viscosity coefficient.

[0039] The fan of a turboshaft engine rotates around its central axis. The fan draws in low-speed air from the fuselage boundary layer, which mixes with aviation fuel, combusts, expands, and performs work, driving the turbine bearings and producing exhaust, thus generating thrust. The turboshaft engine's turbine shaft is mechanically connected to a corresponding generator, which is mounted on the accessory gearbox of the corresponding turboshaft engine nacelle. Power is drawn from the high-voltage shaft of the turbine engine. Specifically, the high-voltage shaft drives the central transmission mechanism, which in turn connects to the generator via an accessory, converting the mechanical energy of the turbine engine into electrical energy. For example… Figure 1 As shown.

[0040] For example, the parameters of the generator and the turboshaft engine can be as follows: the generator is preferably a high-power generator, with a total power output of 12MW-20MW for the two generators and a speed range of 3300-5500RPM; the speed range of the turboshaft engine is 12000-20500RPM, its rated power density is not less than 10kW / Kg, its rated efficiency should be 95-98%, and it is cooled by lubricating oil.

[0041] The power distribution subsystem is used for power management and secondary power distribution. Its functions are: first, to provide the electrical power required for the aircraft's thrust; second, to provide the electrical power required for other aircraft systems, such as avionics and hydraulic systems; and third, to provide the electrical power required for cabin air conditioning and cooling air after the APU is removed. Preferably, the power distribution subsystem can be a distribution panel, which is installed in the aft electronic equipment (EE) bay of the aircraft.

[0042] The power managed or configured by the power distribution subsystem includes power from the power generation subsystem. Power from the power generation subsystem may include power generated by the aforementioned generators, or power generated by the aforementioned generators and rectified. If the latter, the power generation subsystem may further include a rectifier for converting the alternating current (AC) generated by the generators into high-voltage direct current (DC), wherein the power from the power generation subsystem is the high-voltage DC power converted by the rectifier. Preferably, the rectifier may be a rectifier with parameters such as: a rated output voltage of 1028VDC, a rated power density of not less than 18kW / kg, a rated efficiency of 98-99%, and cooling via a propylene glycol-water mixture.

[0043] The electric propulsion system of the aircraft may also include an energy storage subsystem, and the power managed or configured by the power distribution subsystem may also include power from the energy storage subsystem.

[0044] Preferably, the energy storage subsystem includes a lithium battery pack (the energy storage subsystem can also be called a lithium battery system), and the power from the energy storage subsystem includes the power from the lithium battery pack. The power generation subsystem provides steady-state power, while the lithium batteries provide / absorb transient power. The parameters of the assembled lithium battery pack are, for example, an energy density of not less than 600-800 Wh / kg.

[0045] The energy storage subsystem may also include some accessories for the lithium battery pack, such as converters and heat dissipation devices, as is the case in Example 1.

[0046] The aircraft's electric propulsion system may also include fuel cells (or fuel cell systems), and the power managed or configured by the power distribution subsystem may also include power from the fuel cells. The fuel cells are used to provide steady-state power.

[0047] Preferably, the power distribution subsystem may include a power management system (or energy management system), which is used to distribute power according to a power distribution strategy. The aforementioned distribution panel may be part of the power management system, which may also include a power management controller. Specifically, the power management system obtains the status of electrical equipment such as generators, lithium battery packs, fuel cells, and propulsion motors through the power management controller, and sends power distribution commands and propulsion motor control commands to the power management controller; it obtains the status of the turboshaft engine through the engine control system and sends the required thrust commands to the turboshaft engine's engine controller to control the turboshaft engine's operating state.

[0048] Specific power distribution strategies include:

[0049] 1) During the taxiing and taxiing phases of the aircraft, the energy storage subsystem provides separate power to supply taxiing thrust.

[0050] 2) During the takeoff, climb, cruise, and approach phases of the aircraft, the power generation subsystem and the energy storage subsystem jointly provide the required thrust, and switch and redistribute the energy sources according to the thrust requirements of the entire aircraft.

[0051] 3) During the descent phase, the power generation subsystem charges the energy storage subsystem in the air to provide energy for the next ground electric glide.

[0052] Preferably, when the lithium battery's SOC (State of Charge: the available state of the remaining charge in the battery) reaches a preset condition (e.g., the lithium battery's SOC is lower than a preset value), the power generation subsystem and / or fuel cell supply power to the lithium battery.

[0053] The aircraft's electric propulsion system may also include a frequency converter, which converts direct current (DC) from the power distribution subsystem into alternating current (AC) and supplies the converted AC to the propulsion subsystem. Preferably, the frequency converter is a frequency inverter (or motor controller), installed in the forward EE compartment. The inverter's parameters include, for example: a rated input voltage of 1028VDC, a rated power density of not less than 20kW / kg, a rated efficiency of 98-99%, and cooling via a propylene glycol-water mixture.

[0054] In Embodiment 1, the propulsion subsystem may include an electric motor (or propulsion motor) and a propeller. The electric motor converts electrical energy into mechanical energy (i.e., the propulsion work of the aircraft), drives the propeller to rotate, and provides thrust to the aircraft.

[0055] The electrical energy received by the motor can come from the aforementioned frequency converter. Preferably, the motor is mounted on the leading edge of the aircraft's wing. Motor parameters include, for example: a speed range of 3300-5500 RPM, a rated power density of not less than 10 kW / kg, a rated efficiency of 95-98%, and cooling via lubricating oil / deionized water (water + propylene glycol).

[0056] The propeller (or electric propulsion propeller) is connected to a motor or motor reducer and rotates under the drive of the motor or motor reducer, providing the thrust required by the aircraft. Propeller parameters include, for example, a speed range of 3000-3500 RPM.

[0057] In Example 1, the design parameters of the aircraft's electric propulsion system include power transmission efficiency, the proportion of battery energy in the total aircraft energy, and component power density.

[0058] Among them, the power transmission efficiency η Tr The expression is as follows (1):

[0059] η Tr =η G *η R *η PL *η C *η M (1)

[0060] In equation (1): η G For the total generator efficiency, η R For the rectifier efficiency, η PL For the efficiency of the power distribution device, η C For the efficiency of the frequency converter controller, η M This represents the total motor efficiency.

[0061] Total energy efficiency η of the aircraft Ov The expression is as follows (2):

[0062] ηOv =η th *η Tr *η P =P req / P supply =F N *V / (P batt + P fuel (2)

[0063] In equation (2): η th For the conversion efficiency of all turboshaft engines, η P For the propulsion efficiency of all thrusters, P req P is the total power required by the aircraft. supply P is the total power that the entire aircraft can provide. batt P is the power that the lithium battery pack can provide. fuel For the power that fuel can provide, F N V represents the thrust required by the aircraft, and V represents the aircraft's flight speed.

[0064] Power P from fuel fuel The expression is as follows:

[0065] P fuel =m fuel *FHV;

[0066] Where, m fuel FHV represents the fuel flow rate, and FHV represents the calorific value of the fuel.

[0067] The expression for the proportion of electrical energy to the total propulsion energy of an aircraft, Θ, is as follows:

[0068] Θ=P SUPPLY_Elec / P tot

[0069] Among them, P SUPPLY_Elec The power provided by electrical energy, P tot Total propulsion power.

[0070] Some technical specifications of the aircraft's electric propulsion system are shown in Table 1 below (Table 1 is for illustrative purposes only):

[0071]

[0072] Table 1

[0073] The following is combined with Figures 2 to 5 Taking a traditional cylindrical-wing aircraft as an example, the content of Embodiment 1 will be further explained:

[0074] refer to Figure 2 A pair of high-pressure turboshaft engines (i.e., core engines) are installed on both sides of the tail of the aircraft fuselage. Figure 3 As shown), these are designated as the left and right engines (here, "left" and "right" are used only to distinguish the engines and are not used to limit specific locations or directions, nor are they used to limit Embodiment 1). Each turboshaft engine 1 is connected to a generator, and the two generators form a generator set 2. Each generator is connected to a rectifier 3, and both the rectifier 3 and the lithium battery pack 8 are connected to a distribution panel box 4, which is connected to a frequency converter 5. The rectifier 3, lithium battery pack 8, distribution panel box 4, and frequency converter 5 can be arranged sequentially along the aircraft fuselage centerline or along the direction from the tail to the nose.

[0075] Multiple motors 6 are installed on each of the two wings of the aircraft, and frequency converters 5 are connected to each motor 6. The multiple motors 6 on a single wing are arranged and distributed in sequence along the extension direction of the wing, with a certain distance between adjacent motors 6. Each motor 6 is connected to an electric propeller 7, that is, the electric propellers 7 on both sides of the fuselage are also distributed.

[0076] The above components can be connected in a suitable manner. For example, the turboshaft engine 1 and the generator can be mechanically connected, and some components can be connected by high-voltage cables 10 for transmitting current or high-voltage current. Specific connection methods are not limited in Embodiment 1.

[0077] refer to Figure 4 and Figure 5 In practical applications, two turboshaft engines 1 and a generator set 2, installed at the tail of the fuselage, are used to generate all the electrical energy required by the entire aircraft. Simultaneously, the boundary layer airflow at the tail of the fuselage can be utilized to improve the propulsion efficiency of the turboshaft engines 1. A rectifier 3 is used to convert the alternating current generated by the generator into high-voltage direct current, thereby improving the overall power transmission efficiency of the aircraft.

[0078] The lithium battery pack 8 provides auxiliary power to the aircraft. The distribution panel 4 is used to further distribute the DC power converted by the rectifier 3 and the DC power generated by the lithium battery pack 8 to power the entire aircraft. The frequency converter 5 receives the high-voltage DC power distributed by the distribution panel 4, converts it into AC power, and supplies the AC power to each motor 6. The motor 6 converts electrical energy into mechanical energy, driving the electric propeller 7 to rotate, which provides the aircraft with propulsion power.

[0079] The entire machine's electrical power can be transmitted via cable 10.

[0080] refer to Figure 5Two generators provide 1028V high-voltage direct current, which, combined with fuel cells and lithium batteries, provides auxiliary power. Four power channels are centrally located within the high-voltage direct current distribution system (including the distribution panel and frequency converter) to power each motor. The generator subsystem and fuel cell system provide steady-state power, while the lithium battery system provides / absorbs transient power. When the state of charge (SOC) of the lithium batteries in the battery pack is low, for example, below a preset value, the generator subsystem and fuel cell system can charge the lithium batteries.

[0081] The power management system can exchange information with other systems, and specific interconnection commands include, for example... Figure 6 As shown.

[0082] Example 1 can achieve the following beneficial effects:

[0083] The power architecture scheme that utilizes the turboshaft engine at the tail of the fuselage to extract electrical energy involves installing the turboshaft engine at the tail of the aircraft and using the boundary layer airflow at the tail of the fuselage to draw in the low-speed air from the boundary layer of the fuselage into the turboshaft engine. This can effectively improve the working efficiency of the turboshaft engine, thereby improving the power generation efficiency of the power generation subsystem and the propulsion efficiency of the aircraft.

[0084] Specifically, Embodiment 1 employs two turboshaft engines with dual air intakes at the rear of the fuselage, achieving an aerodynamic layout based on BLI technology. This active intake into the fuselage boundary layer reduces air resistance, improves propulsion efficiency, and lowers fuel consumption. Furthermore, using two turboshaft engines increases power redundancy and simplifies the design of the power system.

[0085] Multiple distributed all-electric propellers are installed on the wings. Even if some power units (including a single motor and / or a single propeller) fail, the other power units can still provide thrust to the aircraft, thus improving the safety of the aircraft.

[0086] The scheme described in Example 1 can provide and transmit high-voltage direct current, such as 1024V, and the power transmission efficiency from the generator to the propulsion motor is not less than 90%-94%, improving the overall power transmission efficiency of the aircraft. Furthermore, the overall power density of the aircraft's electric propulsion system (excluding the lithium battery and thermal management system, which will be described below) is not less than 1.2-1.8 kW / kg.

[0087] Through the coordination of the power generation subsystem, power distribution subsystem, energy storage subsystem, etc., and in accordance with the power distribution strategy, the energy system of the whole machine can be aggregated and redistributed to improve the power utilization efficiency.

[0088] Example 1 has broad application prospects and can be applied to subsonic / high subsonic aircraft, including general aviation, regional and single-aisle low subsonic passenger aircraft, cargo aircraft and drones, etc., which can improve the integrated design capability of aircraft-propulsion.

[0089] The second embodiment of this specification (hereinafter referred to as "Embodiment Two") provides a wing-distributed electric propeller propulsion aircraft, which includes the electric propulsion system of the aircraft described in Embodiment One.

[0090] A specific example of Embodiment 2 is as follows: Figure 2 As shown, a combined aircraft design using dual-side air intakes (i.e., twin turboshaft engines) BLI technology at the tail of the fuselage, combined with turboshaft engine electric extraction (i.e., drawing power from the power generation subsystem), and distributed electric propellers mounted on the wings is used in a conventional configuration aircraft.

[0091] In Embodiment 2, the aircraft further includes a thermal management system, which manages the aircraft's heat dissipation and / or air conditioning system, and draws power from the power generation subsystem.

[0092] refer to Figure 4 The thermal management system 9 is used for unified planning of all electrical components of the aircraft. As an example, the thermal management system 9 includes a fuel circulation subsystem, using fuel as the primary heat sink. This subsystem connects the various components of the electric propulsion system. Fuel supplied from the wing fuel tanks is transported sequentially along fuel pipelines to the corresponding subsystems or components of the aircraft's electric propulsion system, such as the power distribution subsystem, energy storage subsystem, and motors in the propulsion subsystem. Part of the fuel is used to cool the corresponding subsystems or components, while another part is pressurized by a booster pump and mixed with the fuel that has passed through the corresponding subsystems or components and absorbed heat, before entering the turboshaft engine at the tail. Furthermore, the thermal management system 9 can allocate fuel consumption according to the turboshaft engine's operating state. If the turboshaft engine is operating at low thrust, excess fuel is mixed with cold air from the environmental control system and then delivered to the cabin. The overall power density of the thermal management system 9 is not less than 0.68-0.8 kW / kg.

[0093] The environmental control system draws power from the power distribution subsystem, such as the high-voltage DC busbar in the distribution panel, and extracts 115V / 400Hz three-phase AC power through a DC-AC converter. The backup air supply provides the air flow required for starting the aforementioned turboshaft engine and the air conditioning unit through an electric compressor.

[0094] In addition, such as Figure 2 As shown, a wingtip propeller 11 is installed at the wingtip of the aircraft wing to reduce the induced drag caused by the pressure difference between the upper and lower parts of the wingtip.

[0095] For details not described in Example 2, please refer to Example 1. Example 2 can achieve the same beneficial effects as Example 1, and the various examples can be used in combination.

[0096] The above description is merely an embodiment of this specification and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. An electric propulsion system for an aircraft, characterized in that, The system includes a power generation subsystem, a power distribution subsystem, and a propulsion subsystem. The power generation subsystem includes a turboshaft engine and a generator. The turboshaft engine is located at the tail of the aircraft and is used to drive the generator to generate electricity; wherein, the fan of the turboshaft engine is used to draw low-speed air from the fuselage boundary layer into the turboshaft engine; The power distribution subsystem is used to distribute power to the propulsion subsystem, which drives the aircraft; wherein the power includes power from the power generation subsystem.

2. The system as described in claim 1, characterized in that, The aircraft has two turboshaft engines, which are installed on both sides of the tail section. Each turboshaft engine drives a generator.

3. The system as described in claim 1, characterized in that, The power generation subsystem also includes a rectifier, which is used to convert the alternating current generated by the generator into high-voltage direct current, and the power from the power generation subsystem is the high-voltage direct current.

4. The system as described in claim 1, characterized in that, The system also includes a frequency converter, which converts the DC power from the power distribution subsystem into AC power and supplies the converted AC power to the propulsion subsystem.

5. The system as described in claim 1, characterized in that, The system also includes an energy storage subsystem, and the power includes power from the energy storage subsystem.

6. The system as described in claim 5, characterized in that, The energy storage subsystem includes a lithium battery pack; wherein the power generation subsystem is used to provide steady-state power, and the lithium battery is used to provide / absorb transient power; or, The energy storage subsystem includes a lithium battery pack. When the state of charge (SOC) of the lithium battery reaches a preset condition, the power generation subsystem supplies power to the lithium battery.

7. The system as described in claim 1, characterized in that, The power distribution subsystem includes a power management system, which is used to distribute power according to a power distribution strategy.

8. The system as described in any one of claims 1 to 7, characterized in that, The propulsion subsystem includes a motor and a propeller; the motor is used to convert electrical energy into mechanical energy, drive the propeller to rotate, and provide thrust for the aircraft.

9. A wing-mounted distributed electric propeller propulsion aircraft, characterized in that, The aircraft includes the aircraft electric propulsion system according to any one of claims 1 to 7.

10. The aircraft as claimed in claim 9, characterized in that, The aircraft also includes a thermal management system for managing the aircraft's heat dissipation and / or air conditioning system, and the thermal management system draws power from the power generation subsystem.

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