Power distribution network system of electric propulsion aircraft

Abstract

A power distribution network system of an electric propulsion aircraft belongs to the field of aircraft power distribution. The direct-current generator power supply serves as main power supply equipment of an aircraft, is arranged in the center of the aircraft and is connected with an engine and a nearest distribution box. All the power distribution boxes are arranged in a multi-step ring shape from the center to the edge of the airplane, the adjacent step rings and the power distribution boxes located in the same step ring are connected with one another, meanwhile, the power distribution boxes need to be arranged nearby according to distribution of loads on the airplane, and a spider net-shaped structure with the center power distribution box as the net center is formed; each distribution box is connected with an energy storage power supply or a direct-current generator power supply which is configured with the distribution box, one distribution box is selected to be connected with a ground direct-current power supply, and the distribution box is connected with a load close to the distribution box. The method has the advantages of higher system redundancy, higher reliability and higher safety.

Description

Technical Field

[0001] The invention belongs to the field of aircraft power distribution, and in particular relates to a power distribution network system for an electric propulsion aircraft. Background Art

[0002] The present invention relates to a power distribution system for an electric propulsion aircraft. The thrust of a traditional aircraft mainly comes from the engine, and the demand for electric energy is mainly from airborne equipment, etc. The power demand is relatively small. The total power demand of the aircraft generally does not exceed 400kW, and generally does not exceed 1MW. The power distribution network is relatively simple. The main power supply mainly comes from a generator, and the capacity is generally 30kW to 250kW. Energy storage power supplies such as batteries are mainly used as emergency power supplies, and the capacity is generally around 20kW. The capacity is very small. The high-power loads of the traditional power distribution system are mainly some oil pumps, etc., and the power distribution network can be made relatively simple.

[0003] With the development of aviation electrification, electric propulsion aircraft has become a trend. Electric propulsion aircraft require a large number of distributed electric motor-driven propellers or ducted fans as propulsion power. The demand for electric power is increasing. According to the needs of aircraft, it is generally above 1MW. A single power supply cannot meet the demand. Distributed power supplies in various forms are required to provide sufficient power. In order to safely and reliably distribute the power of high-power power supplies to the load, a high-efficiency, high-reliability, high-safety, and high-redundancy distribution network suitable for high-power distributed electric propulsion aircraft is required. It is necessary to innovatively design a distribution network topology and structure based on the power demand of new electric propulsion aircraft. Summary of the invention

[0004] The existing technology is mainly designed for power distribution networks with low power, low voltage and low current loads. The present invention designs a DC power distribution system for electric propulsion aircraft for applications of hybrid power sources such as high-power distributed energy storage power sources and high-power density generators. It adopts an innovative power distribution network topology structure, which can achieve efficient, highly safe and reliable power distribution for distributed hybrid power sources and distributed power loads. The power distribution system network can allow the network to be reconstructed after a fault occurs, thereby ensuring the normal operation of the maximum capacity power supply and key important loads, and meeting the electric propulsion aircraft's requirements for high power-to-weight ratio, high efficiency, high reliability and high safety of large-capacity power distribution systems.

[0005] The present invention proposes for the first time a distributed power distribution network structure suitable for electric propulsion aircraft, which can meet the power distribution needs of medium and large power electric propulsion aircraft and lay a foundation for the development of hybrid vertical take-off and landing UAVs and electric vertical take-off and landing UAVs. The technical solution of the present invention is as follows:

[0006] A power distribution network system for an electric propulsion aircraft includes a DC power supply, an energy storage power supply, a distribution box, a load, cables, and a fault detection unit. The DC power supply includes a DC generator power supply and a ground DC power supply;

[0007] The DC generator power supply is the main power supply equipment of the electric propulsion aircraft, which is set at the center of the electric propulsion aircraft and connected to the engine and its nearest distribution box; all the distribution boxes are arranged in a multi-step ring from the center to the edge of the electric propulsion aircraft, and the adjacent step rings and the distribution boxes in the same step ring are connected to each other. At the same time, the layout of the distribution box needs to be arranged nearby according to the distribution of the load on the electric propulsion aircraft, forming a spider web structure with the central distribution box as the core; each distribution box is connected to the energy storage power supply or DC generator power supply configured by each, and one of the distribution boxes is selected to be connected to the ground DC power supply, and the distribution box is connected to the load close to it. When the electric propulsion aircraft is in the flight phase, the DC generator power supply is given priority to power supply, followed by the energy storage power supply; when the electric propulsion aircraft is in the ground working phase, the ground DC power supply is used to charge the energy storage power supply and provide power supply for the operation of the electric propulsion aircraft.

[0008] Furthermore, the DC generator power supply includes a generator and a detection and control protector; the DC generator power supply converts the chemical energy of aviation fuel into mechanical energy through the engine, and then converts it into electrical energy through the generator to maintain a high endurance time.

[0009] Further, the DC generator power supply can be replaced by a combination of an AC generator and AC / DC, which can convert AC power into DC power.

[0010] Further, the ground DC power supply includes a ground power supply monitor;

[0011] Furthermore, the ground DC power supply is a ground power charging pile or a ground power vehicle.

[0012] Furthermore, the energy storage power supply can be charged by a ground DC power supply, and can store excess electric energy generated by a DC generator power supply;

[0013] Furthermore, the energy storage power source is a battery, a fuel cell or a supercapacitor;

[0014] Furthermore, the distribution box determines whether the energy storage power supply needs to be connected to the power grid. When a storage power supply failure is detected, the faulty energy storage power supply is cut off, and the power of the nearest non-faulty energy storage power supply is distributed to the load of this distribution box, thereby ensuring the redundancy of the power supply system and allowing the majority of loads to operate normally.

[0015] Furthermore, the load is a motor load, a propeller load driven by a motor, a ducted fan load driven by a motor, an actuator load, an oil pump load, a fan load, a pulse load or a weapon mission load.

[0016] Furthermore, the motor load includes a motor and an inverter, and has communication, control and protection functions for the motor.

[0017] Furthermore, the fault detection unit is used to detect various faults in the power grid, adjust the structure of the power grid according to mission requirements and current status, ensure the normal operation of the power grid, and provide safe and reliable power for the aircraft.

[0018] Beneficial effects of the present invention: The present invention proposes a new distributed power distribution network structure for electric propulsion aircraft, and proposes a layout structure of power distribution equipment on the aircraft according to the requirements of distributed electric propulsion aircraft. The present invention can realize the power distribution management of the hybrid power system, realize the fault detection and system reconstruction of the power distribution system, and compared with the traditional power distribution system, the present invention has higher system redundancy, higher reliability and safety. The power distribution network of the present invention can be applied not only to residential transport aircraft, airplanes, helicopters, but also to the power distribution systems of aircraft such as eVTOL and flying cars. It is the basis of the next generation of aircraft power distribution systems, has a broad market, and can bring huge economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the structure diagram of the power distribution network.

[0020] Figure 2 It is a spatial location relationship diagram for distribution network equipment.

[0021] In the figure: 10a the first DC generator power supply; 10b the second DC generator power supply; 11a the first energy storage power supply; 11b the second energy storage power supply; 11c the third energy storage power supply; 11d the fourth energy storage power supply; 11e the fifth energy storage power supply; 12 ground DC power supply; 20a the first distribution box; 20b the second distribution box; 20c the third distribution box; 20d the fourth distribution box; 20e the fifth distribution box; 30a the first load; 30b the second load; 30c the third load; 30d the fourth load; 30e the fifth load; 30f the sixth load; 30g the seventh load; 30h the eighth load; 40 the fault detection unit. DETAILED DESCRIPTION

[0022] A power distribution network system for an electric propulsion aircraft includes a DC power supply, an energy storage power supply, a distribution box, a load, cables, and a fault detection unit. Figure 1 .

[0023] The DC power supply includes a DC generator power supply (GEN) and a ground DC power supply (GP);

[0024] The DC generator power supply includes a generator and a detection and control protector; the DC generator power supply uses a generator to convert the rotational mechanical energy of the engine generated by the combustion of chemical energy (such as aviation fuel) into electrical energy to maintain a high endurance. In this embodiment, two DC generator power supplies are provided, namely a first DC generator power supply 10a and a second DC generator power supply 10b; they are respectively provided on the left and right sides of the center of the aircraft, and are mutually redundant.

[0025] The ground DC power supply 12 includes a ground power supply monitor; it can be a ground power supply charging pile or a ground power supply vehicle, etc. In this embodiment, one is provided.

[0026] The energy storage power supply (EP) includes a detection unit, a protection unit, a control unit, a communication unit and a BMS (voltage and current detection unit); the detection unit is used to monitor the voltage, current, temperature of the battery cell and estimate the capacity of the battery, the protection unit is used to implement overvoltage, undervoltage, overcurrent and other protections for the battery, the control unit is used to control the battery's grid-in and grid-out control and pre-charging circuit control, etc., the communication unit is used to upload the battery's status information to the host computer through bus communication, and the BMS is used to implement battery management. The energy storage power supply can be charged by a ground DC power supply, and store the excess electric energy generated by a DC generator power supply; this embodiment is provided with 5 units, namely the first energy storage power supply 11a, the second energy storage power supply 11b, the third energy storage power supply 11c, the fourth energy storage power supply 11d and the fifth energy storage power supply 11e; the energy storage power supply is a battery, a fuel cell or a supercapacitor.

[0027] The power distribution box (PDH) contains busbars, contactors, voltage and current detection units, and control protection and communication units; busbars are used for power distribution, contactors are used to connect and disconnect power or loads, voltage and current detection units are used to collect the voltage of the busbars in the distribution box and the current of the load, and control protection and communication units are used to realize power distribution protection and communication with the host computer. The distribution box determines whether the energy storage power supply needs to be connected to the power grid. When a storage power supply failure is detected, the faulty energy storage power supply is cut off, and the power of the nearest energy storage power supply without failure is distributed to the load of this distribution box, ensuring the redundancy of the distribution system and allowing the most loads to work normally. For example, when the third energy storage power supply 11c fails, the fault detection unit 40 will detect the fault information, control the third distribution box 20c to make the third energy storage power supply 11c exit the power grid, thereby ensuring the normal operation of the power grid, and will also control the second energy storage power supply 11b, the fourth energy storage power supply 11d, and the fifth energy storage power supply 11e to evenly supply the power to the fifth load 30e and the sixth load 30f carried by the third distribution box 20c. For example, when the motor of the fifth load 30e has an overcurrent or short circuit fault, the sensor of the voltage and current detection unit in the third distribution box 20c will detect the current overcurrent, control the contactor to disconnect the fifth load 30e, cut off the fault source from the power grid, and ensure the normal operation of the power grid. The status will be transmitted to the fault detection unit 40 in a timely manner. This embodiment is provided with 5 units, namely the first distribution box 20a, the second distribution box 20b, the third distribution box 20c, the fourth distribution box 20d and the fifth distribution box 20e. Figure 1 , Figure 2 shown.

[0028] The load (M) may be a motor load, a propeller load driven by a motor, or a ducted fan load, but is not limited thereto. It may also be a high-power load such as an actuator, an oil pump, a fan, or even a high-power pulse load or a weapon mission load. A general motor load includes a motor and an inverter, and has the communication, control, and protection functions of the motor. The motor load includes a motor and an inverter, and has the communication, control, and protection functions of the motor. In this embodiment, 8 loads are set, and the setting positions are as follows: Figure 1 , Figure 2 shown.

[0029] The fault detection unit 40 is used to detect various faults in the power grid (e.g., over-voltage, under-voltage, over-current, short circuit, power grid contactor fault, power supply fault, motor load fault, etc.), adjust the structure of the power grid according to the mission requirements and the current state, ensure the normal operation of the power grid, and provide safe and reliable power for the aircraft. The fault information in the power distribution system can be stored and analyzed, and communicated to the flight control and avionics systems.

[0030] The loads are distributed at different locations of the aircraft as required, the DC generator power supply and the energy storage power supply are distributed at different locations of the aircraft as required, and the distribution boxes are also distributed in the aircraft accordingly. The entire power grid embodies the characteristics of distributed intelligence and can improve the redundancy and reliability of the distribution system.

[0031] Pure electric aircraft cannot meet the long-term and long-distance endurance requirements due to the low specific power and specific energy of energy storage power sources such as batteries. In order to improve the endurance, a hybrid power system is needed, that is, the engine needs to burn fossil fuels to convert chemical energy into rotational mechanical energy, and then convert the mechanical energy into electrical energy through a generator. At this time, the aircraft can increase its range and endurance based on the fuel carried, and the 10ab generator power supply will provide electricity during cruising.

[0032] According to the mission profile of the vertical take-off and landing electric propulsion aircraft, the power consumption is the highest during take-off, hovering and landing, and 10ab and 11abcde are required to jointly provide power for the 30 motor. When entering the cruising phase, the load's demand for power decreases. In addition to supplying the load with the power generated by 10ab, the excess power can be stored in the energy storage power supply 11 for standby use. In situations where high power output is required, such as hovering, the generator and the energy storage power supply jointly supply power to the load, thereby realizing peak shaving and valley filling and peak shifting management of power.

Claims

1. A power distribution network system for an electric propulsion aircraft, characterized in that: It includes a DC power supply, an energy storage power supply, a distribution box, a load, cables and a fault detection unit; the DC power supply includes a DC generator power supply and a ground DC power supply; The DC generator power supply is the main power supply equipment of the electric propulsion aircraft, which is arranged at the center of the electric propulsion aircraft and connected to the engine and its nearest distribution box; all the distribution boxes are arranged in a multi-step ring from the center to the edge of the electric propulsion aircraft, and the adjacent step rings and the distribution boxes in the same step ring are connected to each other. At the same time, the layout position of the distribution box needs to be arranged nearby according to the distribution of the load on the electric propulsion aircraft, forming a spider web structure with the central distribution box as the core; each distribution box is connected to the energy storage power supply or DC generator power supply configured by itself, and one of the distribution boxes is selected to be connected to the ground DC power supply, and the distribution box is connected to the load close to it; when the electric propulsion aircraft is in the flight phase, the DC generator power supply is given priority to power supply, followed by the energy storage power supply; When the electric propulsion aircraft is in the ground working stage, the ground DC power supply is used to charge the energy storage power supply and provide power for the operation of the electric propulsion aircraft.

2. A power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The DC generator power supply includes a generator and a detection and control protector; the DC generator power supply converts the chemical energy of aviation fuel into mechanical energy through the engine, and then converts it into electrical energy through the generator to maintain a high endurance time.

3. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The DC generator power supply can be replaced by an AC generator and AC / DC combination, which is able to convert AC power into DC power.

4. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The ground DC power supply includes a ground power supply monitor; the ground DC power supply is a ground power supply charging pile or a ground power supply vehicle.

5. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The energy storage power supply can be charged by a ground DC power supply, and can store excess electric energy generated by a DC generator power supply.

6. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The energy storage power source is a battery, a fuel cell or a super capacitor.

7. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The distribution box determines whether the energy storage power supply needs to be connected to the power grid. When a storage power supply failure is detected, the faulty energy storage power supply is cut off, and the power of the nearest non-faulty energy storage power supply is distributed to the load of this distribution box, ensuring the redundancy of the power supply system and allowing the majority of loads to operate normally.

8. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The load is a motor load, a motor-driven propeller load, a motor-driven ducted fan load, an actuator load, an oil pump load, a fan load, a pulse load or a weapon mission load.

9. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The motor load comprises a motor and an inverter, and has the communication, control and protection functions of the motor.

10. The power distribution network system for an electric propulsion aircraft according to claim 1, characterized in that: The fault detection unit is used to detect various faults in the power grid, adjust the structure of the power grid according to mission requirements and current status, ensure the normal operation of the power grid, and provide safe and reliable electric energy for the aircraft.

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