Aircraft hybrid power supply system and power supply control method

Abstract

The invention discloses an aircraft hybrid power supply system and a power supply control method, which can be combined with a fuel cell system, a photovoltaic cell system and a power cell system to form a comprehensive airborne energy source and have the advantages of high output power, high response speed and long endurance time. And the output states of the fuel cell system, the photovoltaic cell system and the power cell system can be regulated and controlled in real time according to the full-aircraft load power, the power cell system can be charged and discharged in time while airborne energy is not used, and the instantaneous airborne energy consumption increasing requirement can be met in time.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft hybrid power supply, and particularly relates to an aircraft hybrid power supply system and a power supply control method. Background Art

[0002] With the proposal of the concept of green aviation and the development of electrification, in recent years, more and more power forms that drive motors with battery, hydrogen fuel cell, and solar energy as energy outputs have emerged in the aircraft field. The development of all-electric aircraft is relatively mature, with the advantage of large instantaneous output power, but the disadvantage is that the mass power density of the battery is relatively low, and the cruise time of the aircraft is short, generally only a dozen to dozens of minutes; solar aircraft have a long endurance time under specific meteorological conditions, but have high requirements for meteorological conditions; fuel cells have a relatively long endurance time, but the disadvantage is that the response is slow and the power increase speed within a short time is limited.

[0003] When combining two or more of the energy forms of battery, hydrogen fuel cell, and solar energy to achieve energy supply, how to make up for each other's strengths and weaknesses through a control scheme on the aircraft to achieve fast, stable, and long-term energy output is a relatively urgent challenge currently faced.

[0004] Therefore, in view of the problem that power batteries, fuel cells, and solar photovoltaic cells have not been comprehensively applied in aircraft energy supply in the prior art, the present invention discloses an aircraft hybrid power supply system and a power supply control method. Summary of the Invention

[0005] The present invention discloses an aircraft hybrid power supply system and a power supply control method, which combine a power battery, a solar photovoltaic cell, and a fuel cell as hybrid electric energy to provide aircraft energy, and at the same time have the advantages of large instantaneous output power, fast output power response, and long endurance time to meet the comprehensive requirements of the aircraft for energy output.

[0006] The present invention is achieved through the following technical solutions: An aircraft hybrid power supply system includes a power supply bus, and further includes a fuel cell system, a power battery system, and a photovoltaic cell system. The fuel cell system and the photovoltaic cell system are unidirectionally connected in parallel to the power supply bus, so that the fuel cell system and the photovoltaic cell system can only supply power to the power supply bus unidirectionally; the power battery system is bidirectionally connected in parallel to the power supply bus, so that the power battery system can supply power to the power supply bus or draw power from the power supply bus. A low-voltage branch is provided at the output end of the power battery system, and the low-voltage branch is connected to an aircraft low-voltage power consumption system; an electronic speed control component is provided at the output end of the power supply bus, and the output end of the electronic speed control component is connected to a propeller system.

[0007] To better implement the present invention, further, the fuel cell system includes a fuel cell module and a DC converter, and the fuel cell module is connected to the power supply bus through the DC converter; the photovoltaic cell system includes a solar photovoltaic panel module and a photovoltaic inverter, and the solar photovoltaic panel module is connected to the power supply bus through the photovoltaic inverter.

[0008] To better implement the present invention, further, the propeller system includes a motor and a propeller module, the motor is connected to the output end of the electronic speed control component, and the output end of the motor is connected to the propeller module; the airborne low-voltage power consumption system includes a buck module and an airborne low-voltage power consumption module, and the low-voltage branch is connected to the airborne low-voltage power consumption module through the buck module.

[0009] An aircraft hybrid power supply control method, implemented based on an aircraft hybrid power supply system, includes the following steps: Step 1, judge the state of the propeller system. If the propeller system is in a stopped state, go to Step 2; if the propeller system is in an operating state, go to Step 3; set a first power threshold K1, a second power threshold K2, and a third power threshold K3, and K1>K2>K3; Step 2, detect the real-time power soc of the power battery system. If soc≥K1, keep the fuel cell system and the photovoltaic cell system in a standby state; if soc<K1, compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system, and control the photovoltaic cell system to charge the power battery system alone or control the photovoltaic cell system and the fuel cell system to charge the power battery system together according to the comparison result; Step 3, detect the real-time power soc of the power battery system. If soc<K3, go to Step 4; if K3≤soc≤K2, go to Step 5; if K2<soc<K1, go to Step 6; if soc≥K1, go to Step 7; Step 4, detect the full-aircraft load power PM and the maximum output power PFC1 of the fuel cell system. If PM≤PS0, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to jointly perform the first-mode power supply; if PS0<PM<PS0+PFC1, control the photovoltaic cell system and the fuel cell system to jointly perform the second-mode power supply; if PM≥PS0+PFC1, control the photovoltaic cell system and the fuel cell system to jointly perform the third-mode power supply; Step 5: Detect the full machine load power PM and the maximum output power PFC1 of the fuel cell system. If PM ≤ PS0, control the photovoltaic cell system to supply power in the fourth mode alone. If PS0 < PM < PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power jointly in the fifth mode. If PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power jointly in the sixth mode. Step 6: Detect the full machine load power PM and the maximum output power PFC1 of the fuel cell system. If PM ≤ PS0, control the photovoltaic cell system to supply power in the seventh mode alone. If PS0 < PM < PS0 + PFC1, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to supply power jointly in the eighth mode. If PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power jointly in the ninth mode. Step 7: Keep the photovoltaic cell system and the fuel cell system in the standby state.

[0010] To better implement the present invention, further, the specific steps of step 2 include: Step 2.1: Detect the real-time power soc of the power battery system. Step 2.2: If soc ≥ K1, keep the fuel cell system and the photovoltaic cell system in the standby state, and supply power to the low-voltage branch through the power battery system. If soc < K1, compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system. Step 2.3: If PS0 > PB0, adjust the output power PS1 of the photovoltaic cell system to PS1 = PB0 for the photovoltaic cell system, and charge the power battery system through the photovoltaic cell system. If PS0 ≤ PB0, start the fuel cell system, detect the minimum output power PFC0 of the fuel cell system, and then go to step 2.4. Step 2.4: If PS0 + PFC0 > PB0, control the real-time output power PFC of the fuel cell system to be PFC = PFC0, and ensure that PFC0 + PS1 = PB0. If PS0 + PFC0 ≤ PB0, control PS1 = PS0, and PFC + PS0 = PB0.

[0011] To better implement the present invention, further, the specific steps of step 4 include: Step 4.1: Detect the full machine load power PM, the maximum output power PFC1 of the fuel cell system, and the maximum allowable charging power PB0 of the power battery system. If PM ≤ PS0, go to step 4.2. If PS0 < PM < PS0 + PFC1, go to step 4.3. If PM ≥ PS0 + PFC1, go to step 4.4. Step 4.2: If PS0 > PB0 + PM, control the output power of the photovoltaic cell system PS1 = PM + PB0, and supply power to the power battery system by controlling the photovoltaic cell system alone; if PS0 ≤ PB0 + PM, start the fuel cell system, detect the minimum output power PFC0 of the fuel cell system. If PFC0 + PS0 > PB0 + PM, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system jointly by the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system jointly by the photovoltaic cell system and the fuel cell system. Step 4.3: Start the fuel cell system. If PFC0 + PS0 > PB0 + PM, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system jointly by the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system jointly by the photovoltaic cell system and the fuel cell system. Step 4.4: Start the fuel cell system, control the real-time output power of the fuel cell system PFC = PFC1 and control the output power of the photovoltaic cell system PS1 = PS0 for combined power supply, and reduce the rotational speed of the propeller system so that PM + PB0 ≤ PFC + PS0.

[0012] To better implement the present invention, further, the specific steps of step 5 include: Step 5.1: If PM ≤ PS0, go to step 5.2; if PS0 < PM < PS0 + PFC1, go to step 5.3; if PM ≥ PS0 + PFC1, go to step 5.4. Step 5.2: Control the output power of the photovoltaic cell system PS1 = PM, and supply power jointly by the photovoltaic cell system and the power battery system. Step 5.3: Start the fuel cell system. If PM < PS0 + PFC0, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PM, and supply power jointly by the photovoltaic cell system, the fuel cell system, and the power battery system; if PM ≥ PS0 + PFC0, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PM, and supply power jointly by the photovoltaic cell system, the fuel cell system, and the power battery system. Step 5.4: Start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0, and control the real-time output power of the fuel cell system PFC = PFC1, and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system.

[0013] To better implement the present invention, further, the specific steps of step 6 are as follows: Step 6.1: Detect the full machine load power PM, detect the maximum output power PFC1 of the fuel cell system, and detect the input power PS0 of the photovoltaic cell system; if PM ≤ PS0, then go to step 6.2; if PS0 < PM < PS0 + PFC1, then go to step 6.3; if PM ≥ PS0 + PFC1, then go to step 6.4; Step 6.2: Control the output power of the photovoltaic cell system PS1 = 0.8PM, and supply power jointly through the photovoltaic cell system and the power battery system; Step 6.3: Detect the minimum output power PFC0 of the fuel cell system. If PM < PS0 + PFC0, then control the output power of the photovoltaic cell system PS1 = PS0, and supply power jointly through the photovoltaic cell system and the power battery system; if PM ≥ PS0 + PFC0, then start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0, and control the real-time output power of the fuel cell system PFC = PFC0, and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system; Step 6.4: Start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0, and control the real-time output power of the fuel cell system PFC = PFC0, and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system.

[0014] To better implement the present invention, further, the first power threshold K1 = 98%; the second power threshold K2 = 80%; the third power threshold K3 = 40%.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention can combine the fuel cell system, the photovoltaic cell system, and the power battery system to form an integrated airborne energy source, which has the advantages of high output power, fast response speed, and long endurance time. Moreover, it can adjust the output states of the fuel cell system, the photovoltaic cell system, and the power battery system in real time according to the full machine load power, and can charge and discharge the power battery system in time while not using the airborne energy source, and can meet the instantaneous increase in airborne energy consumption requirements in time. Description of the Drawings

[0016] Figure 1 It is a schematic diagram of an aircraft hybrid power supply system; Figure 2 Schematic diagram of the power supply control process steps in the stopped state of the propeller system; Figure 3 Schematic diagram of the power supply control process steps in the started state of the propeller system.

[0017] Wherein: 1 - fuel cell module; 2 - DC converter; 3 - solar photovoltaic panel module; 4 - PV inverter; 5 - power battery system; 6 - electronic speed control component; 7 - motor; 8 - propeller module; 9 - buck module; 10 - airborne low-voltage power consumption module. Specific implementation manners

[0018] Embodiment 1: An aircraft hybrid power supply system according to this embodiment, as Figure 1 shown, includes a power supply bus, and further includes a fuel cell system, a power battery system 5, and a photovoltaic cell system. The fuel cell system and the photovoltaic cell system are unidirectionally connected in parallel to the power supply bus, so that the fuel cell system and the photovoltaic cell system can only supply power to the power supply bus unidirectionally; the power battery system 5 is bidirectionally connected in parallel to the power supply bus, so that the power battery system 5 can supply power to the power supply bus or draw power from the power supply bus. A low-voltage branch is provided at the output end of the power battery system 5, and the low-voltage branch is connected to the airborne low-voltage power consumption system; an electronic speed control component 6 is provided at the output end of the power supply bus, and the output end of the electronic speed control component 6 is connected to the propeller system.

[0019] The fuel cell system and the photovoltaic cell system are unidirectionally connected to the power supply bus, that is, only the fuel cell system and the photovoltaic cell system are allowed to supply power to the power supply bus, and the fuel cell system and the photovoltaic cell system are not allowed to draw power from the power supply bus. By providing the fuel cell system and the photovoltaic cell system, they are used to cooperate with the power battery system 5 for combined power supply, or when the power of the power battery system 5 is insufficient, the fuel cell system and the photovoltaic cell system are used to charge the power battery system 5.

[0020] The fuel cell system includes a fuel cell module 1 and a DC converter 2, and the fuel cell module 1 is connected to the power supply bus through the DC converter 2; the photovoltaic cell system includes a solar photovoltaic panel module 3 and a PV inverter 4, and the solar photovoltaic panel module 3 is connected to the power supply bus through the PV inverter 4.

[0021] The fuel cell module 1 adopts a hydrogen fuel cell module, which is used to convert the chemical energy generated by the reaction of hydrogen and oxygen into electrical energy. The DC converter 2 is used to convert the voltage of the direct current generated by the fuel cell module 1 into the working voltage range required by the electronic speed control component 6. The solar photovoltaic module 3 includes solar photovoltaic panels, which are used to convert solar energy into electrical energy. By setting a photovoltaic inverter 4, the maximum efficiency utilization of solar power generation can be achieved, and at the same time, the voltage generated by the solar photovoltaic module 3 can be converted into the working voltage range required by the electronic speed control component 6. The power battery system 5 itself has a certain capacitance and is bidirectionally connected to the power supply bus. Through the power battery system 5, power can be supplied to the power supply bus, and at the same time, the power battery system 5 can also draw power from the power supply bus. The electronic speed control component 6 is used to monitor and control the speed of the motor in the propeller system.

[0022] The propeller system includes a motor 7 and a propeller module 8. The motor 7 is connected to the output end of the electronic speed control component 6, and the output end of the motor 7 is connected to the propeller module 8. The on-board low-voltage power consumption system includes a buck module 9 and an on-board low-voltage power consumption module 10. The low-voltage branch is connected to the on-board low-voltage power consumption module 10 through the buck module 9. The electronic speed control component 6 is used to monitor and control the speed of the motor 7, and drives the propeller module 8 to rotate through the motor 7. At the same time, the output end of the power battery system 5 supplies low-voltage power to the on-board low-voltage power consumption module 10 through the low-voltage branch, and the buck module 9 can convert the voltage output by the power battery system 5 into the working voltage range required by the on-board low-voltage power consumption module 10.

[0023] Embodiment 2: A method for controlling the hybrid power supply of an aircraft according to this embodiment is implemented based on the aircraft hybrid power supply system in Embodiment 1, and includes the following steps: Step 1: Judge the state of the propeller system. If the propeller system is in a stopped state, go to Step 2; if the propeller system is in an operating state, go to Step 3; set a first power threshold K1, a second power threshold K2, and a third power threshold K3, and K1>K2>K3; Step 2: Detect the real-time power soc of the power battery system 5. If soc≥K1, keep the fuel cell system and the photovoltaic cell system in the standby state; if soc<K1, compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system 5, and control the photovoltaic cell system to charge the power battery system 5 alone or control the photovoltaic cell system and the fuel cell system to charge the power battery system 5 together according to the comparison result; Step 3: Detect the real-time power soc of the power battery system 5. If soc<K3, go to Step 4; if K3≤soc≤K2, go to Step 5; if K2<soc<K1, go to Step 6; if soc≥K1, go to Step 7; Step 4, detect the full-machine load power PM and the maximum output power PFC1 of the fuel cell system; if PM ≤ PS0, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to jointly supply power in the first mode; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly supply power in the second mode; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly supply power in the third mode; Step 5, detect the full-machine load power PM and the maximum output power PFC1 of the fuel cell system; if PM ≤ PS0, control the photovoltaic cell system to supply power alone in the fourth mode; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly supply power in the fifth mode; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly supply power in the sixth mode; Step 6, detect the full-machine load power PM and the maximum output power PFC1 of the fuel cell system; if PM ≤ PS0, control the photovoltaic cell system to supply power alone in the seventh mode; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to jointly supply power in the eighth mode; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly supply power in the ninth mode; Step 7, keep the photovoltaic cell system and the fuel cell system in the standby state.

[0024] For the convenience of explanation, the definitions of the following symbols are given here: SOC represents the real-time power of the power battery system 5; PB0 represents the maximum allowable charging power of the power battery system 5; Pm0 represents the load power of the motor in the propeller system; PS0 represents the input power of the photovoltaic cell system; PS1 represents the output power of the photovoltaic cell system; PFC0 represents the minimum output power of the fuel cell system; PFC1 represents the maximum output power of the fuel cell system; PFC represents the real-time output power of the fuel cell system; Pm1 represents the load power of the on-board low-voltage power consumption system; PM represents the full-machine load power.

[0025] Among them, PB0, PFC0, and PFC1 are fixed values; And 0 ≤ PS1 ≤ PS0; the output power PS1 of the photovoltaic cell system can be adjusted in real time, but the maximum output power PS1 of the photovoltaic cell system does not exceed the input power PS0 of the photovoltaic cell system.

[0026] 0 < PFC0 ≤ PFC ≤ PFC1; The real-time output power PFC of the fuel cell system is between the minimum output power PFC0 and the maximum output power PFC1 of the fuel cell system, and the minimum output power PFC0 of the fuel cell system is not zero.

[0027] PM = Pm0 + Pm1; that is, the total aircraft load power is the sum of the load power of the airborne low-voltage power consumption system and the load power of the motor in the propeller system.

[0028] PFC0 ≤ PB0, which means that when selecting the control system, the minimum output power PFC0 of the fuel cell system should not be greater than the maximum allowable charging power PB0 of the power battery system 5.

[0029] When the propeller system is in the stop state, the total aircraft load power mainly comes from the load power of the airborne low-voltage power consumption system, and the total aircraft load power is small at this time. When the propeller system starts, the total aircraft load power comes from the sum of the load power of the airborne low-voltage power consumption system and the load power of the motor in the propeller system, and the total aircraft load power is large at this time.

[0030] Further, when the aircraft is powered on and the propeller system is in the stop state, it first enters the ground inspection stage. In the ground inspection mode of the aircraft, it needs to prepare for flight. Considering that the power consumption is the largest during the takeoff and climb phase of the aircraft, it is necessary to ensure that the power battery system 5 is fully charged or has a relatively high battery level before takeoff. At this time, step 2 is executed, as Figure 2 shown, the specific steps of step 2 include: Step 2.1, Detect the real-time battery level soc of the power battery system 5; Step 2.2, If soc ≥ K1, where K1 = 98% is taken; it is considered that the current battery level state of the power battery system 5 meets the release requirements of the aircraft, then keep the fuel cell system and the photovoltaic cell system in the standby state to prevent the power battery system 5 from being overcharged, and at the same time supply power to the low-voltage branch through the power battery system 5. If soc < K1, at this time, it is necessary to charge the power battery system 5 through the photovoltaic cell system or the fuel cell system.

[0031] Compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system 5, and then transfer to step 2.3; Step 2.3, If PS0 > PB0, then adjust the output power PS1 of the photovoltaic cell system to PS1 = PB0 of the photovoltaic cell system, and charge the power battery system 5 through the photovoltaic cell system; at this time, the photovoltaic cell system is in the state of charging the power battery system 5 and does not consume the energy carried by the aircraft.

[0032] If PS0 ≤ PB0, it is judged whether to start the fuel cell system according to the urgency of the flight mission and the overall aircraft status.

[0033] If the fuel cell system is started, after detecting the minimum output power PFC0 of the fuel cell system, transfer to step 2.4; Step 2.4: If PS0 + PFC0 > PB0, control the real-time output power of the fuel cell system PFC = PFC0, and ensure that PFC0 + PS1 = PB0, that is, the fuel cell system operates at the minimum output power, and the output power of the photovoltaic cell system is adjusted to be equal to the difference between the maximum allowable charging power of the power battery system 5 and the minimum output power of the fuel cell system; if PS0 + PFC0 ≤ PB0, control PS1 = PS0, and PFC + PS0 = PB0, that is, keep the output power of the photovoltaic cell system equal to its input power, and the output power of the fuel cell system is equal to the difference between the maximum allowable charging power of the power battery system 5 and the input power of the photovoltaic cell system.

[0034] Furthermore, if soc < K3, where K3 = 40% is taken, it means that the power battery system 5 has a low power level and a small discharge margin, and it is necessary to charge the power battery system 5 at the maximum charging speed; the overall aircraft energy consumption is moderate, and it is necessary for the fuel cell system and the photovoltaic cell system to generate electricity simultaneously to meet the overall aircraft energy consumption requirements. At this time, execute step 4, as Figure 3 shown, the specific steps of step 4 include: Step 4.1: Detect the overall aircraft load power PM, the maximum output power PFC1 of the fuel cell system, and the maximum allowable charging power PB0 of the power battery system 5; if PM ≤ PS0, transfer to step 4.2; if PS0 < PM < PS0 + PFC1, transfer to step 4.3; if PM ≥ PS0 + PFC1, transfer to step 4.4; Step 4.2: If PS0 > PB0 + PM, control the output power of the photovoltaic cell system PS1 = PM + PB0, and supply power to the power battery system 5 by controlling the photovoltaic cell system alone; if PS0 ≤ PB0 + PM, start the fuel cell system, detect the minimum output power PFC0 of the fuel cell system, if PFC0 + PS0 > PB0 + PM, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system 5 jointly by the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system 5 jointly by the photovoltaic cell system and the fuel cell system; Step 4.3: Start the fuel cell system. If PFC0 + PS0 > PB0 + PM, then control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system 5 through the combined operation of the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, then control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system 5 through the combined operation of the photovoltaic cell system and the fuel cell system. Step 4.4: Start the fuel cell system, control the real-time output power of the fuel cell system PFC = PFC1 and control the output power of the photovoltaic cell system PS1 = PS0 for combined power supply, reduce the rotation speed of the propeller system, so that PM + PB0 ≤ PFC + PS0.

[0035] Furthermore, if K3 ≤ soc ≤ K2, where K2 = 80% and K3 = 40% are taken here. It means that the power of the power battery system 5 is moderate and the discharge margin is appropriate, and the power balance of the power battery system 5 should be ensured; the overall energy consumption of the machine is small, and the power generation power of the photovoltaic cell system can meet the overall energy consumption requirements of the machine. At this time, execute Step 5, as Figure 3 shown, the specific steps of the said Step 5 include: Step 5.1: If PM ≤ PS0, then go to Step 5.2; if PS0 < PM < PS0 + PFC1, then go to Step 5.3; if PM ≥ PS0 + PFC1, then go to Step 5.4; Step 5.2: Control the output power of the photovoltaic cell system PS1 = PM, and supply power through the combined operation of the photovoltaic cell system and the power battery system 5; Step 5.3: Start the fuel cell system. If PM < PS0 + PFC0, then control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PM, and supply power through the combined operation of the photovoltaic cell system, the fuel cell system, and the power battery system 5; if PM ≥ PS0 + PFC0, then control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PM, and supply power through the combined operation of the photovoltaic cell system, the fuel cell system, and the power battery system 5; Step 5.4: Start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0 and control the real-time output power of the fuel cell system PFC = PFC1, and supply power through the combined operation of the photovoltaic cell system, the fuel cell system, and the power battery system 5.

[0036] Furthermore, if K2 < soc < K1, where K1 = 98% and K2 = 80% are taken here. It means that the power of the power battery system 5 is high and the discharge margin is high, and the SOC should be appropriately reduced; the overall energy consumption of the machine is low, and the overall load of the machine is less than the output power of the photovoltaic cell system. At this time, execute Step 6, asFigure 3 As shown, step 6 specifically includes: Step 6.1: Detect the full machine load power PM, detect the maximum output power PFC1 of the fuel cell system, and detect the input power PS0 of the photovoltaic cell system; if PM ≤ PS0, go to step 6.2; if PS0 < PM < PS0 + PFC1, go to step 6.3; if PM ≥ PS0 + PFC1, go to step 6.4; Step 6.2: Control the output power of the photovoltaic cell system PS1 = 0.8PM, and supply power jointly through the photovoltaic cell system and the power battery system 5; Step 6.3: Detect the minimum output power PFC0 of the fuel cell system. If PM < PS0 + PFC0, control the output power of the photovoltaic cell system PS1 = PS0, and supply power jointly through the photovoltaic cell system and the power battery system 5; if PM ≥ PS0 + PFC0, start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0 and control the real-time output power of the fuel cell system PFC = PFC0, and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system 5; Step 6.4: Start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0 and control the real-time output power of the fuel cell system PFC = PFC0, and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system 5.

[0037] Furthermore, if soc ≥ K1, where K1 = 98% is taken. It means that the power battery system 5 is fully charged. To prevent overcharging of the power battery system 5, the photovoltaic cell system and the fuel cell system are kept in the standby state.

[0038] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Any simple modification or equivalent change made to the above embodiments based on the technical essence of the present invention falls within the protection scope of the present invention.

Claims

1. An aircraft hybrid power supply system, including a power supply busbar, characterized in that, It also includes a fuel cell system, a power battery system (5), and a photovoltaic cell system. The fuel cell system and the photovoltaic cell system are unidirectionally connected in parallel to the power supply bus, such that the fuel cell system and the photovoltaic cell system can only supply power to the power supply bus unidirectionally; the power battery system (5) is bidirectionally connected in parallel to the power supply bus, such that the power battery system (5) can supply power to the power supply bus or draw power from the power supply bus. A low-voltage branch is provided at the output end of the power battery system (5), and the low-voltage branch is connected to the on-board low-voltage power consumption system; an electronic speed control component (6) is provided at the output end of the power supply bus, and the output end of the electronic speed control component (6) is connected to the propeller system.

2. The aircraft hybrid power supply system according to claim 1, wherein, The fuel cell system includes a fuel cell module (1) and a DC converter (2), and the fuel cell module (1) is connected to the power supply bus through the DC converter (2); the photovoltaic cell system includes a solar photovoltaic panel module (3) and a photovoltaic inverter (4), and the solar photovoltaic panel module (3) is connected to the power supply bus through the photovoltaic inverter (4).

3. An aircraft hybrid power supply system according to claim 2, characterized in that The propeller system includes a motor (7) and a propeller module (8), the motor (7) is connected to the output end of the electronic speed control component (6), and the output end of the motor (7) is connected to the propeller module (8); the on-board low-voltage power consumption system includes a buck module (9) and an on-board low-voltage power consumption module (10), and the low-voltage branch is connected to the on-board low-voltage power consumption module (10) through the buck module (9).

4. A method for controlling the hybrid power supply of an aircraft, implemented based on the aircraft hybrid power supply system according to any one of claims 1-3, characterized in that, It includes the following steps: Step 1: Determine the state of the propeller system. If the propeller system is in a stopped state, go to Step 2; if the propeller system is in an operating state, go to Step 3; Set a first power threshold K1, a second power threshold K2, and a third power threshold K3, and K1 > K2 > K3; Step 2: Detect the real-time power soc of the power battery system (5). If soc ≥ K1, keep the fuel cell system and the photovoltaic cell system in a standby state; if soc < K1, compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system (5), and control the photovoltaic cell system to charge the power battery system (5) alone or control the photovoltaic cell system and the fuel cell system to charge the power battery system (5) together according to the comparison result; Step 3: Detect the real-time power soc of the power battery system (5). If soc < K3, go to Step 4; if K3 ≤ soc ≤ K2, go to Step 5; if K2 < soc < K1, go to Step 6; if soc ≥ K1, go to Step 7; Step 4: Detect the total machine load power PM and the maximum output power PFC1 of the fuel cell system. If PM ≤ PS0, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to jointly perform the first mode of power supply; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly perform the second mode of power supply; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to jointly perform the third mode of power supply; Step 5, detect the full-machine load power PM, and detect the maximum output power PFC1 of the fuel cell system; if PM ≤ PS0, control the photovoltaic cell system to supply power in the fourth mode alone; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power in the fifth mode jointly; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power in the sixth mode jointly; Step 6, detect the full-machine load power PM, and detect the maximum output power PFC1 of the fuel cell system; if PM ≤ PS0, control the photovoltaic cell system to supply power in the seventh mode alone; if PS0 < PM < PS0 + PFC1, control the photovoltaic cell system alone or control the photovoltaic cell system and the fuel cell system to supply power in the eighth mode jointly; if PM ≥ PS0 + PFC1, control the photovoltaic cell system and the fuel cell system to supply power in the ninth mode jointly; Step 7, keep the photovoltaic cell system and the fuel cell system in the standby state.

5. A method for controlling the hybrid power supply of an aircraft according to claim 4, characterized in that, The specific content of step 2 includes: Step 2.1, detect the real-time power soc of the power battery system (5); Step 2.2, if soc ≥ K1, keep the fuel cell system and the photovoltaic cell system in the standby state, and supply power to the low-voltage branch through the power battery system (5); if soc < K1, compare the input power PS0 of the photovoltaic cell system with the maximum allowable charging power PB0 of the power battery system (5); Step 2.3, if PS0 > PB0, adjust the output power PS1 of the photovoltaic cell system to PS1 = PB0, and charge the power battery system (5) through the photovoltaic cell system; if PS0 ≤ PB0, start the fuel cell system, and after detecting the minimum output power PFC0 of the fuel cell system, transfer to step 2.4; Step 2.4, if PS0 + PFC0 > PB0, control the real-time output power PFC of the fuel cell system to be PFC = PFC0, and ensure that PFC0 + PS1 = PB0; if PS0 + PFC0 ≤ PB0, control PS1 = PS0, and PFC + PS0 = PB0.

6. The aircraft hybrid power supply control method according to claim 4, wherein The specific content of step 4 includes: Step 4.1, detect the full-machine load power PM, the maximum output power PFC1 of the fuel cell system, and the maximum allowable charging power PB0 of the power battery system (5); if PM ≤ PS0, transfer to step 4.2; if PS0 < PM < PS0 + PFC1, transfer to step 4.3; if PM ≥ PS0 + PFC1, transfer to step 4.4; Step 4.2: If PS0 > PB0 + PM, control the output power of the photovoltaic cell system PS1 = PM + PB0, and supply power to the power battery system (5) by controlling the photovoltaic cell system alone; if PS0 ≤ PB0 + PM, start the fuel cell system, detect the minimum output power PFC0 of the fuel cell system, if PFC0 + PS0 > PB0 + PM, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system (5) jointly by the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system (5) jointly by the photovoltaic cell system and the fuel cell system. Step 4.3: Start the fuel cell system. If PFC0 + PS0 > PB0 + PM, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PB0 + PM, and supply power to the power battery system (5) jointly by the photovoltaic cell system and the fuel cell system; if PFC0 + PS0 ≤ PB0 + PM, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PB0 + PM, and supply power to the power battery system (5) jointly by the photovoltaic cell system and the fuel cell system. Step 4.4: Start the fuel cell system, control the real-time output power of the fuel cell system PFC = PFC1 and control the output power of the photovoltaic cell system PS1 = PS0 for joint power supply, and reduce the rotation speed of the propeller system so that PM + PB0 ≤ PFC + PS0.

7. A method for controlling the hybrid power supply of an aircraft according to claim 4, characterized in that, The specific steps of step 5 are as follows: Step 5.1: If PM ≤ PS0, go to step 5.2; if PS0 < PM < PS0 + PFC1, go to step 5.3; if PM ≥ PS0 + PFC1, go to step 5.

4. Step 5.2: Control the output power of the photovoltaic cell system PS1 = PM, and supply power jointly by the photovoltaic cell system and the power battery system (5). Step 5.3: Start the fuel cell system. If PM < PS0 + PFC0, control the real-time output power of the fuel cell system PFC = PFC0 and PS1 + PFC0 = PM, and supply power jointly by the photovoltaic cell system, the fuel cell system and the power battery system (5); if PM ≥ PS0 + PFC0, control the output power of the photovoltaic cell system PS1 = PS0 and PFC + PS0 = PM, and supply power jointly by the photovoltaic cell system, the fuel cell system and the power battery system (5). Step 5.4: Start the fuel cell system, control the output power of the photovoltaic cell system PS1 = PS0 and control the real-time output power of the fuel cell system PFC = PFC1, and supply power jointly by the photovoltaic cell system, the fuel cell system and the power battery system (5).

8. A method for controlling the hybrid power supply of an aircraft according to claim 4, characterized in that, The specific steps of step 6 are as follows: Step 6.1: Detect the full machine load power \(P_M\), detect the maximum output power \(P_{FC1}\) of the fuel cell system, and detect the input power \(P_{S0}\) of the photovoltaic cell system; if \(P_M\leq P_{S0}\), go to Step 6.2; if \(P_{S0}\lt P_M\lt P_{S0}+P_{FC1}\), go to Step 6.3; if \(P_M\geq P_{S0}+P_{FC1}\), go to Step 6.4; Step 6.2: Control the output power of the photovoltaic cell system \(P_{S1}=0.8P_M\), and supply power jointly through the photovoltaic cell system and the power battery system (5); Step 6.3: Detect the minimum output power \(P_{FC0}\) of the fuel cell system. If \(P_M\lt P_{S0}+P_{FC0}\), control the output power of the photovoltaic cell system \(P_{S1}=P_{S0}\), and supply power jointly through the photovoltaic cell system and the power battery system (5); if \(P_M\geq P_{S0}+P_{FC0}\), start the fuel cell system, control the output power of the photovoltaic cell system \(P_{S1}=P_{S0}\) and control the real-time output power of the fuel cell system \(P_{FC}=P_{FC0}\), and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system (5); Step 6.4: Start the fuel cell system, control the output power of the photovoltaic cell system \(P_{S1}=P_{S0}\) and control the real-time output power of the fuel cell system \(P_{FC}=P_{FC0}\), and supply power jointly through the photovoltaic cell system, the fuel cell system, and the power battery system (5).

9. A method for controlling an aircraft hybrid power supply according to any one of claims 4-8, characterized in that The first power threshold \(K1 = 98\%\); the second power threshold \(K2 = 80\%\); the third power threshold \(K3 = 40\%\).

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