Double-engine unmanned aerial vehicle power distribution system architecture power distribution system and power distribution method

Abstract

The invention relates to a double-generator unmanned aerial vehicle power distribution system architecture power distribution system and a power distribution method, and solves the problem that a main generator and a standby generator of an existing power distribution system fail when an engine fails. Comprising a primary power distribution system, a secondary power distribution system, a bus bar control unit BPCU and two electrical load management centers ELMC, the BPCU is responsible for primary power distribution control, and the ELMC is responsible for secondary power distribution control; the BPCU is provided with five power input sources, namely a left generator, a right generator, two ground power supplies and an emergency storage battery pack, and the BPCU distributes the power input sources to seven internal bus bars according to preset logic, namely a left / right generator bus bar, a left / right task bus bar, a left / right key bus bar and a storage battery bus bar; and the two electrical load management centers respectively obtain electric power from the front seven bus bars, and distribute the electric power to the terminal loads through internal SSPCs or direct connection lines. The method can prevent task equipment faults from affecting whole-aircraft power supply, and improves the reliability of fault isolation.

Description

Technical Field

[0001] The present invention relates to the architecture of a power distribution system for a twin-engine unmanned aerial vehicle and automatic logic conversion technology under different power supply states, and in particular to a power distribution system and a power distribution method for a power distribution system architecture for a twin-engine unmanned aerial vehicle. Background Art

[0002] The power distribution system is one of the most important systems of drones. It is responsible for distributing the generator power, emergency power, etc. on drones to the onboard electrical equipment. Currently, most drones are powered by a single engine, and twin-engine drones are relatively rare. The power distribution system architecture is mainly based on a single generator, with a relatively simple structure. The reliability and redundancy are difficult to meet the use requirements of twin-engine drones.

[0003] The core of the UAV power distribution system is the busbar control unit (hereinafter referred to as BPCU), which controls the on and off of the busbars through built-in logic. According to the power consumption of the electrical load of the electrical equipment of the whole machine and the power supply priority analysis, several busbars of different levels or types are set. The connection or disconnection light conversion logic between the busbars is controlled by the busbar control unit. The power supply conditions of the twin-engine UAV are roughly divided into ground power supply status, dual-engine normal power supply status, single-engine failure status, emergency power supply status, etc. The busbar control unit collects the status of relevant parameters on the machine in real time, and automatically controls the power supply status conversion according to the parameter status.

[0004] The current mainstream UAV power distribution system is divided into two levels of bus bars. The main generator supplies power to the primary bus bar. The primary bus bar and the backup generator are connected in parallel to the secondary bus bar through diodes. The main and backup generators are driven by the same engine. Under normal circumstances, the main generator supplies power to all onboard equipment. When the main generator fails, the backup generator supplies power to onboard equipment related to flight safety. The disadvantage of this architecture is that it cannot maximize the efficiency of the main and backup power supplies. Most of the backup generators are in an unloaded state, and when the engine fails, both the main and backup generators will fail. Summary of the invention

[0005] The dual-generation power distribution architecture of the present invention can not only solve the above-mentioned problems, but also has a task bus in its design compared to the conventional power distribution system architecture. The task bus is used to supply power to the task equipment. When a short circuit or other fault occurs in the task equipment, the path between the generator bus and the task bus can be cut off to prevent the failure of the mission equipment from affecting the power supply of the entire machine, thereby improving the reliability of fault isolation.

[0006] The present invention provides a power distribution system architecture for a twin-engine UAV, the reliability and redundancy of which can meet the use requirements of the twin-engine UAV.

[0007] The present invention is achieved by the following technical solutions:

[0008] A twin-engine UAV power distribution system architecture. The twin-engine UAV power distribution system adopts a two-level distributed power distribution method and is divided into left and right distribution channels. The first-level distribution system reasonably distributes the main power supply and emergency power supply to the bus bars at each level, and performs power conversion according to the different working modes of the power supply system; the second-level distribution system distributes the power to the power load, and is responsible for the power on and off control of the load, switch status collection and reporting, overcurrent and short-circuit protection, and the distribution system can collect power system parameters and report them to the bus.

[0009] The power distribution system architecture of the twin-engine UAV according to the above architecture includes a primary power distribution system, a secondary power distribution system, a bus control unit BPCU and two electrical load management centers ELMC, wherein the BPCU is responsible for primary power distribution control and the ELMC is responsible for secondary power distribution control;

[0010] BPCU has five power input sources, namely left and right generators, two ground power supplies and an emergency battery pack. BPCU distributes these power input sources to seven internal buses according to preset logic, namely: left / right generator bus, left / right mission bus, left / right key bus, battery bus;

[0011] Among them, the left / right generator busbars are used to receive the input of ground power and generator power, and the loads are important power-consuming equipment that needs to be powered when the aircraft is powered by a single engine; the left / right key busbars are used to load equipment that needs to be powered when the aircraft is powered by an emergency engine; the battery busbars are used to provide switch-converted power to the power distribution equipment when the aircraft is on the ground and there is no ground power input, and to supply power to the key busbar when the aircraft is started using the onboard power supply; the left / right mission busbars are used to supply power to the aircraft's mission equipment, and can be unloaded in the single-engine power supply and emergency power supply states;

[0012] The two electrical load management centers draw power from the first seven bus bars and distribute it to the terminal loads via internal SSPCs or direct lines.

[0013] The aircraft's power conversion relationship at different stages and the switching logic between buses are preset in the bus control unit, and all conversions are completed automatically.

[0014] The architecture does not include left / right mission bus bars, and mission equipment faults are isolated through secondary power distribution devices.

[0015] The twin-engine UAV power distribution system according to the above architecture includes a primary distribution bus control unit BPCU, a left electrical load management center, a right electrical load management center, a ground power supply, a starting battery pack, an emergency battery pack, left and right starter generators G1 and G2, left and right starter generator controllers GCU1 and GCU2, a left generating bus, a right generating bus, a left mission bus, a left and right mission bus, a left key bus, a right key bus, a battery bus, left and right generator grid-connected contactors GCB1 and GCB2, and a left , two right generator starting contactors GCB3 and GCB4, three busbar grid-connected contactors B1, B2 and B3, two task busbar unloading contactors R1 and R2, two ground power grid-connected contactors K1 and K2, and one emergency battery grid-connected contactor K3. GCU1 controls GCB1 and GCB3, and GCU2 controls GCB2 and GCB4. GCB1 is connected between G1 and the left generating busbar, GCU2 is connected between G2 and the right generating busbar, GCB3 is connected between the starting battery group and G1, and GCB4 is connected Connected between the starting battery pack and G2, the ground power supply is connected to the left generating bus through K1, and the other way is connected to the right generating bus through K2. B1 is connected between the left generating bus and the right generating bus, R1 is connected between the left generating bus and the left mission bus, and R2 is connected between the right generating bus and the right mission bus. The left generating bus and the right generating bus are connected to the left key bus and the right key bus through diodes respectively. The left key bus and the right key bus are connected to the battery bus through B2 and B3 respectively. The emergency battery pack is connected to the left generating bus through the diode. Through K3 and the battery bus connection, the left generation bus, left mission bus, left key bus and one end of the battery bus are connected to the left electrical load management center, and the right generation bus, right mission bus, right key bus and the other end of the battery bus are connected to the right electrical load management center. The left and right electrical load management centers obtain power from the first 7 buses respectively, and distribute it to the terminal load through the internal SPC or direct line. B1, B2, B3, R1, R2, K1, K2, and K3 are controlled by the primary distribution bus control unit BPCU.

[0016] The starting battery pack and the emergency battery pack are the same battery pack.

[0017] After passing through the diode K3, the emergency battery pack does not pass through the battery bus bar, but is directly connected to the left key bus bar and the right key bus bar through B2 and B3 respectively.

[0018] The contactor is an electromechanical contactor or a solid-state power controller.

[0019] The power distribution method of the above-mentioned twin-engine UAV power distribution system includes five states, namely, ground power supply state, engine starting power supply state, dual generator normal power supply state, single generator failure power supply state and emergency battery emergency power supply state. The BPCU automatically switches according to each power supply state;

[0020] (1) Ground power supply status

[0021] When the UAV platform is under ground maintenance, it can be powered by ground power. When the ground power quality meets the requirements, the ground power is connected to the aircraft power grid, K1 and K2 are closed, the ground power supplies power to the left / right generator bus, the left / right generator bus supplies power to the left / right key bus respectively, the left generator bus supplies power to the left mission bus through R1, and the right generator bus supplies power to the right mission bus through R2;

[0022] (2) Engine starting power supply status

[0023] The two engines need to be started separately. Taking the starting of the left generator as an example, GCU1 controls GCB3 to close, the starting battery pack provides starting power, and the emergency battery pack supplies power to key electrical equipment. At this time, GCB1 and GCB2 are disconnected, K3, B2, and B3 are closed, and the emergency battery pack supplies power to the left / right key buses through the battery bus;

[0024] (3) Normal power supply status of dual generators

[0025] The power system is in normal power supply state, GCB1 and GCB2 are closed, the left and right generators supply power to the left and right generator buses respectively, the left / right generator buses supply power to the left / right key buses respectively, R1 and R2 are closed, the left generator bus supplies power to the left task bus, and the right generator bus supplies power to the right task bus;

[0026] (4) Single generator failure power supply state

[0027] When the aircraft is in the air, if only one of the left and right generators can produce power, then this generator will supply power to the important electrical equipment of the whole aircraft. When the right generator fails and the left generator supplies power, compared with the normal power supply state of the power system, GCB2 is disconnected, B1 is closed, the left generator bus supplies power to the right generator bus, R1 and R2 are disconnected, and the left / right task bus is unloaded; when the left generator fails and the right generator supplies power, compared with the normal power supply state of the power system, GCB1 is disconnected, B2 is closed, the right generator bus supplies power to the left generator bus, R1 and R2 are disconnected, and the left / right task bus is unloaded;

[0028] (5) Emergency battery emergency power supply status

[0029] When the aircraft is in the air, if both generators cannot supply power normally, the battery system will supply power to key electrical equipment. At this time, GCB1 and GCB2 are disconnected, B2 and B3 are closed, and the battery bus supplies power to the left / right key bus.

[0030] The busbar control unit BPCU automatically controls the on and off of each contactor through a built-in program according to external input and collected information. The on and off logic of each contactor is as follows:

[0031] 1) K1 control logic

[0032] When the external power quality is qualified, the left generator maintenance switch is closed, and the GCB1 contactor is disconnected, K1 is closed; when the external power status is undervoltage, overvoltage or overcurrent protection, K1 is disconnected;

[0033] 2) K2 control logic

[0034] When the external power quality is qualified, the left generator maintenance switch is closed, and the GCB2 contactor is disconnected, K2 is closed; when the external power status is undervoltage, overvoltage or protection, K2 is disconnected;

[0035] 3) B1 control logic

[0036] When only one of GCB1 and GCB2 is closed, and K1 and K2 are open, B1 is closed, otherwise B1 is open;

[0037] 4) B2 / B3 control logic

[0038] When at least one of GCB1 and GCB2 is disconnected, the ground power supply is not connected, and the battery bus is powered, B2 and B3 are closed at the same time. In other cases, B2 and B3 are disconnected;

[0039] 5) R1 control logic

[0040] When either GCB1 or GCB2 is disconnected or the left generator bus is overloaded, R1 is disconnected; otherwise, R1 is closed;

[0041] 6) R2 control logic

[0042] When either GCB1 or GCB2 is disconnected or the right generator bus is overloaded, R2 is disconnected; otherwise, R2 is closed;

[0043] 7) K3 control logic

[0044] When the ground-to-air switch that controls the grid connection of the emergency battery is unplugged, K3 is connected to the grid.

[0045] Beneficial effects and advantages of the present invention:

[0046] 1. The power conversion relationship of the aircraft at different stages and the switching logic between buses are preset in the bus control unit, and all conversions are completed automatically;

[0047] 2. Through the setting of busbars, during the normal power supply period of dual generators, both generators are outputting power, which improves the power utilization rate;

[0048] 3. Through the setting of battery bus bars, some special equipment that require uninterrupted power supply can be powered by key bus bars and battery bus bars in parallel, so that the power supply will not be interrupted during power conversion due to generator failure or other reasons;

[0049] 4. The left / right task bus bars are set separately to isolate the task equipment when it fails, so that the power grid failure will not be caused by the task equipment failure, thus improving the fault isolation.

[0050] 5. The starting battery group and the emergency battery group in the architecture are two separate groups of batteries, and can also be combined into one group of batteries. This solution does not affect the automatic conversion of the distribution architecture.

[0051] 6. The contactors in the architecture can be traditional electromechanical contactors or solid-state power control technology. The solid-state power controller can replace the contactor. The solid-state power controller unit consists of an internal power supply, self-detection circuit, short-circuit protection, isolation control, drive and I2T delay trigger circuit. It can not only realize the on and off of the power channel, but also monitor the voltage and current of the load line in real time, and has overvoltage protection and overcurrent protection functions.

[0052] 7. When designing the scheme, the left / right mission bus bar setting can be cancelled, and the mission equipment fault can be isolated through the secondary distribution device, but this scheme will reduce the reliability of some fault isolation. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The power distribution architecture of the twin-engine UAV of the present invention;

[0054] Figure 2 The ground power supply state of the present invention;

[0055] Figure 3 The power supply configuration for starting the engine of the present invention (starting the left engine as an example);

[0056] Figure 4 This is the normal power supply state of the dual generators of the present invention;

[0057] Figure 5 This is the power supply state of a single generator failure of the present invention (taking the failure of the right generator as an example);

[0058] Figure 6 The emergency power supply state of the emergency storage battery of the present invention;

[0059] Figure 7 This is the K1 logic control diagram of the present invention;

[0060] Figure 8 This is the K2 logic control diagram of the present invention;

[0061] Fig. 9 This is the B1 logic control diagram of the present invention;

[0062] Fig.10 This is the B2 / B3 logic control diagram of the present invention;

[0063] Fig.11 This is the R1 logic control diagram of the present invention;

[0064] Fig.12 This is the R2 logic control diagram of the present invention;

[0065] Fig.13 This is the K3 logic control diagram of the present invention. DETAILED DESCRIPTION

[0066] The power distribution system of the twin-engine UAV in the present invention adopts a two-level distributed distribution method and is divided into left and right distribution channels. The first-level distribution system reasonably distributes the main power supply and emergency power supply to the bus bars at each level, and performs power conversion according to the different working modes of the power supply system; the second-level distribution system distributes the power to the power load, and is responsible for the power on and off control of the load, the acquisition and reporting of the switch status, and the overcurrent and short-circuit protection. The distribution system can collect the power system parameters and report them to the bus. Figure 1 For the twin-engine drone Figure 1 As shown, G1 and G2 are two starter generators, GCU1 and GCU2 are two starter generator controllers, GCB1 and GCB2 are generator grid-connected contactors; GCB3 and GCB4 are starter generator starting contactors, B1, B2, and B3 are busbar grid-connected contactors, R1 and R2 are task busbar unloading contactors, K1 and K2 are ground power grid-connected contactors, and K3 is an emergency battery grid-connected contactor. Among them, GCU1 controls GCB1 and GCB3, GCU2 controls GCB2 and GCB4, and B1, B2, B3, R1, R2, K1, K2, and K3 are controlled by the primary distribution busbar control unit (BPCU).

[0067] Figure 1 The power distribution system architecture of the twin-engine UAV includes three line replaceable units (LRUs), namely a bus bar control unit (BPCU) and two electrical load management centers (ELMCs). The BPCU is responsible for primary power distribution control, and the ELMC is responsible for secondary power distribution control.

[0068] BPCU has 5 power input sources, including left and right generators, two ground power supplies and an emergency battery pack. BPCU distributes these power input sources to 7 internal buses according to preset logic, including left / right generator bus, left / right mission bus, left / right key bus, and battery bus.

[0069] Among them, the left / right generator bus is used to receive the input of ground power supply and generator power supply, and the load hung is the important power-consuming equipment that needs electricity in the single-engine power supply state of the aircraft; the left / right key bus is used to carry the equipment that needs electricity in the emergency power supply state of the aircraft; the battery bus has the following functions: first, when the aircraft is on the ground and there is no ground power input, the battery bus can provide switch conversion power to the distribution equipment; second, when the aircraft uses the onboard power supply to start, it supplies power to the key bus; the left / right mission bus is used to supply power to the aircraft's mission equipment, which can be unloaded in the single-engine power supply and emergency power supply states.

[0070] The two electrical load management centers (ELMC1 and ELMC2) draw power from the first seven bus bars and distribute it to the terminal loads through internal SSPCs or direct lines.

[0071] The primary power distribution system of a twin-engine UAV implements different power supply configurations according to the status of each power system and the flight phase. The power supply configuration mainly has five states, which are divided into ground power supply state, engine start power supply state, dual generator normal power supply state, single generator failure power supply state (left generator failure power supply state or right generator failure power supply state), and emergency battery emergency power supply state. The BPCU can automatically switch according to the power supply state.

[0072] (1) Ground power supply status

[0073] When the UAV platform is under ground maintenance, it can be powered by ground power. When the ground power quality meets the requirements, the ground power is connected to the aircraft power grid. K1 and K2 are closed, the ground power supplies power to the left / right generator bus, the left / right generator bus supplies power to the left / right key bus respectively, the left generator bus supplies power to the left mission bus through R1, and the right generator bus supplies power to the right mission bus through R2. The ground maintenance power supply status is as follows: Figure 2 shown.

[0074] (2) Engine starting power supply status

[0075] The two engines need to be started separately. Taking the left generator as an example, GCU1 controls GCB3 to close, the starting battery pack provides starting power, and the emergency battery pack supplies power to key electrical equipment. At this time, GCB1 and GCB2 are disconnected, K3, B2, and B3 are closed, and the emergency battery pack supplies power to the left / right key buses through the battery bus. The engine starting power supply status (starting the left generator as an example) is as follows Figure 3 shown.

[0076] (3) Normal power supply status of dual generators

[0077] The power system is in normal power supply state. GCB1 and GCB2 are closed, and the left and right generators supply power to the left and right generator buses respectively. The left / right generator buses supply power to the left / right key buses respectively. R1 and R2 are closed, the left generator bus supplies power to the left task bus, and the right generator bus supplies power to the right task bus. The power system double-generator normal power supply state is as follows: Figure 3 shown.

[0078] (4) Single generator failure power supply state

[0079] When the aircraft is in the air, if only one of the left and right generators can produce power, the generator will supply power to all important electrical equipment in the aircraft. When the right generator fails and the left generator supplies power, compared with the normal power supply state of the power system, GCB2 is disconnected, B1 is closed, and the left generator bus supplies power to the right generator bus. R1 and R2 are disconnected, and the left / right task bus is unloaded. The power supply state of the power system when a single engine fails is as follows Figure 5 shown.

[0080] (5) Emergency battery emergency power supply status

[0081] When the aircraft is in the air, if both generators cannot supply power normally, the battery system will supply power to the key electrical equipment. At this time, GCB1 and GCB2 are disconnected, B2 and B3 are closed, and the battery busbar supplies power to the left / right key busbars. The emergency power supply status of the power system is as follows: Figure 6 shown.

[0082] In the present invention, the bus bar control unit (BPCU) can automatically control the on and off of each contactor through a built-in program according to external input and collected information. The on and off logic of each contactor is as follows:

[0083] 1) K1 control logic

[0084] When the external power quality is qualified, the left generator maintenance switch is closed, and the GCB1 contactor is disconnected, K1 is closed; when the external power status is undervoltage, overvoltage or overcurrent protection, K1 is disconnected; Figure 7 shown.

[0085] 2) K2 control logic

[0086] When the external power quality is qualified, the left generator maintenance switch is closed, and the GCB2 contactor is disconnected, K2 is closed; when the external power status is undervoltage, overvoltage or protection, K2 is disconnected; Figure 8 shown.

[0087] 3) B1 control logic

[0088] When only one of GCB1 and GCB2 is closed, and K1 and K2 are open, B1 is closed, otherwise B1 is open; Fig. 9 shown.

[0089] 4) B2 / B3 control logic

[0090] When at least one of GCB1 and GCB2 is disconnected, the ground power supply is not connected, and the battery bus is powered, B2 and B3 are closed at the same time. In other cases, B2 and B3 are disconnected; Fig.10 shown.

[0091] 5) R1 control logic

[0092] When either GCB1 or GCB2 is disconnected or the left generator bus is overloaded, R1 is disconnected; otherwise, R1 is closed; Fig.11 shown.

[0093] 6) R2 control logic

[0094] When either GCB1 or GCB2 is disconnected or the right generator bus is overloaded, R2 is disconnected; otherwise, R2 is closed; Fig.12 shown.

[0095] 7) K3 control logic

[0096] When the ground-to-air switch controlling the grid connection of the emergency battery is unplugged, K3 is connected to the grid; Fig.13 shown.

[0097] The core of the twin-engine UAV power distribution system of the present invention is the bus control unit (hereinafter referred to as BPCU), which controls the on and off of the bus bars through built-in logic. According to the power consumption of the electrical load of the electrical equipment of the whole machine and the power supply priority analysis, several bus bars of different levels or types are set. The connection or disconnection light conversion logic between the bus bars is controlled by the bus control unit. The power supply conditions of the twin-engine UAV are roughly divided into ground power supply status, engine start power supply status, dual-engine normal power supply status, single-engine failure status, emergency power supply status, etc. The bus control unit collects the status of relevant parameters on the machine in real time, and automatically controls the power supply status conversion according to the parameter status.

[0098] In the present invention:

[0099] 1. The starting battery group and the emergency battery group in the architecture can be combined into one battery group;

[0100] 2. The battery busbar can be eliminated, and the battery is connected to the left / right key busbars through two contactors after passing through the diode;

[0101] 3. The contactors in the architecture can be traditional electromechanical contactors or solid-state power control technology. The solid-state power controller can replace the contactor. The solid-state power controller unit consists of an internal power supply, self-detection circuit, short-circuit protection, isolation control, drive and I2T delay trigger circuit. It can not only realize the on and off of the power channel, but also monitor the voltage and current of the load line in real time, and has overvoltage protection and overcurrent protection functions.

[0102] 4. The left / right mission bus bar setting can also be cancelled, and the mission equipment fault can be isolated through the secondary distribution device, which will reduce the reliability of some fault isolation.

Claims

1. A dual-engine UAV power distribution system architecture, characterized by: The power distribution system of twin-engine UAV adopts a two-level distributed distribution method and is divided into left and right distribution channels. The first-level distribution system reasonably distributes the main power supply and emergency power supply to the bus bars at all levels, and performs power conversion according to the different working modes of the power supply system; the second-level distribution system distributes power to the power load, and is responsible for the power on and off control of the load, switch status collection and reporting, overcurrent and short-circuit protection. The distribution system can collect power system parameters and report them to the bus.

2. According to claim 1, a dual-engine UAV power distribution system architecture is characterized by: The power distribution system architecture of the twin-engine UAV includes a primary power distribution system, a secondary power distribution system, a bus control unit BPCU and two electrical load management centers ELMC, wherein the BPCU is responsible for primary power distribution control and the ELMC is responsible for secondary power distribution control; BPCU has five power input sources, namely left and right generators, two ground power supplies and an emergency battery pack. BPCU distributes these power input sources to seven internal buses according to preset logic, namely: left / right generator bus, left / right mission bus, left / right key bus, battery bus; Among them, the left / right generator busbars are used to receive the input of ground power and generator power, and the loads are important power-consuming equipment that needs to be powered when the aircraft is powered by a single engine; the left / right key busbars are used to load equipment that needs to be powered when the aircraft is powered by an emergency engine; the battery busbars are used to provide switch-converted power to the power distribution equipment when the aircraft is on the ground and there is no ground power input, and to supply power to the key busbar when the aircraft is started using the onboard power supply; the left / right mission busbars are used to supply power to the aircraft's mission equipment, and can be unloaded in the single-engine power supply and emergency power supply states; The two electrical load management centers draw power from the first seven bus bars and distribute it to the terminal loads via internal SSPCs or direct lines.

3. According to the twin-engine UAV power distribution system architecture of claim 2, it is characterized by: The power conversion relationship at different stages and the switching logic between buses are preset in the bus control unit, and all conversions are completed automatically.

4. The power distribution system architecture of a twin-engine UAV according to claim 2 is characterized by: The architecture does not include left / right mission bus bars, and mission equipment faults are isolated through secondary power distribution devices.

5. A power distribution system for a twin-engine UAV, characterized by: It includes a primary distribution bus control unit BPCU, a left electrical load management center, a right electrical load management center, a ground power supply, a starting battery pack, an emergency battery pack, left and right starter generators G1 and G2, left and right starter generator controllers GCU1 and GCU2, a left generating bus, a right generating bus, a left mission bus, a left mission bus, a left key bus, a right key bus, a battery bus, left and right generator grid-connected contactors GCB1 and GCB2, left and right generator starting contactors GCB3 and GCB4, three bus grid-connected contactors B1, B2 and B3, two mission bus unloading contactors R1 and R2, two ground power grid-connected contactors K1 and K2, and an emergency battery grid-connected contactor K3; GCU1 controls GCB1 and GCB3, GCU2 controls GCB2 and GCB4, GCB1 is connected between G1 and the left generating bus, GCU2 is connected between G2 and the right generating bus, GCB3 is connected between the starting battery pack and G1, GCB4 is connected between the starting battery pack and G2, one way of the ground power supply is connected to the left generating bus through K1, and the other way is connected to the right generating bus through K2, B1 is connected between the left generating bus and the right generating bus, R1 is connected between the left generating bus and the left mission bus, R2 is connected between the right generating bus and the right mission bus, the left generating bus and the right generating bus are connected through diodes and the left key bus and the right key bus respectively. The left key bus and the right key bus are connected to the battery bus through B2, B3 respectively, the emergency battery group is connected to the battery bus through K3 after passing through a diode, the left generating bus, the left mission bus, the left key bus and one end of the battery bus are connected to the left electrical load management center, the right generating bus, the right mission bus, the right key bus and the other end of the battery bus are connected to the right gas load management center, the left and right electrical load management centers obtain power from the first 7 buses respectively, and distribute it to the terminal load through the internal SPC or direct line, B1, B2, B3, R1, R2, K1, K2, K3 are controlled by the primary distribution bus control unit BPCU.

6. A twin-engine UAV power distribution system according to claim 5, characterized in that: The starting battery pack and the emergency battery pack are the same battery pack.

7. A twin-engine UAV power distribution system according to claim 5, characterized in that: After passing through the diode K3, the emergency battery pack does not pass through the battery bus bar, but is directly connected to the left key bus bar and the right key bus bar through B2 and B3 respectively.

8. The power distribution system for a twin-engine UAV according to claim 5 is characterized by: The contactor is an electromechanical contactor or a solid-state power controller.

9. A twin-engine UAV power distribution system according to claim 5, characterized in that: The busbar control unit BPCU automatically controls the on and off of each contactor through a built-in program according to external input and collected information. The on and off logic of each contactor is as follows: 1) K1 control logic When the external power quality is qualified, and the left generator maintenance switch is closed, and the GCB1 contactor is disconnected, K1 is closed; When the external power supply is in undervoltage, overvoltage or overcurrent protection, K1 is disconnected; 2) K2 control logic When the external power quality is qualified, and the left generator maintenance switch is closed, and the GCB2 contactor is disconnected, K2 is closed; When the external power supply is undervoltage, overvoltage or protection, K2 is disconnected; 3) B1 control logic When only one of GCB1 and GCB2 is closed, and K1 and K2 are open, B1 is closed, otherwise B1 is open; 4) B2 / B3 control logic When at least one of GCB1 and GCB2 is disconnected, the ground power supply is not connected, and the battery bus is powered, B2 and B3 are closed at the same time. In other cases, B2 and B3 are disconnected; 5) R1 control logic When either GCB1 or GCB2 is disconnected or the left generator bus is overloaded, R1 is disconnected; otherwise, R1 is closed; 6) R2 control logic When either GCB1 or GCB2 is disconnected or the right generator bus is overloaded, R2 is disconnected; otherwise, R2 is closed; 7) K3 control logic When the ground-to-air switch that controls the grid connection of the emergency battery is unplugged, K3 is connected to the grid.

10. A power distribution method for a twin-engine UAV power distribution system, characterized by: It includes 4 states, namely ground power supply state, dual generator normal power supply state, single generator failure power supply state and emergency battery emergency power supply state. BPCU automatically switches according to each power supply state; (1) Ground power supply status When the UAV platform is under ground maintenance, it can be powered by ground power. When the ground power quality meets the requirements, the ground power is connected to the aircraft power grid, K1 and K2 are closed, the ground power supplies power to the left / right generator bus, the left / right generator bus supplies power to the left / right key bus respectively, the left generator bus supplies power to the left mission bus through R1, and the right generator bus supplies power to the right mission bus through R2; (2) Engine starting power supply status The two engines need to be started separately. Taking the starting of the left generator as an example, GCU1 controls GCB3 to close, the starting battery pack provides starting power, and the emergency battery pack supplies power to key electrical equipment. At this time, GCB1 and GCB2 are disconnected, K3, B2, and B3 are closed, and the emergency battery pack supplies power to the left / right key buses through the battery bus; (3) Normal power supply status of dual generators The power system is in normal power supply state, GCB1 and GCB2 are closed, the left and right generators supply power to the left and right generator buses respectively, the left / right generator buses supply power to the left / right key buses respectively, R1 and R2 are closed, the left generator bus supplies power to the left task bus, and the right generator bus supplies power to the right task bus; (4) Single generator failure power supply state When the aircraft is in the air, if only one of the left and right generators can produce power, then this generator will supply power to the important electrical equipment of the whole aircraft. When the right generator fails and the left generator supplies power, compared with the normal power supply state of the power system, GCB2 is disconnected, B1 is closed, the left generator bus supplies power to the right generator bus, R1 and R2 are disconnected, and the left / right task bus is unloaded; when the left generator fails and the right generator supplies power, compared with the normal power supply state of the power system, GCB1 is disconnected, B2 is closed, the right generator bus supplies power to the left generator bus, R1 and R2 are disconnected, and the left / right task bus is unloaded; (5) Emergency battery emergency power supply status When the aircraft is in the air, if both generators cannot supply power normally, the battery system will supply power to key electrical equipment. At this time, GCB1 and GCB2 are disconnected, B2 and B3 are closed, and the battery bus supplies power to the left / right key bus.

Images