CN-122009571-A - Cooperative control method for power system of range-extended engine of unmanned aerial vehicle

CN122009571ACN 122009571 ACN122009571 ACN 122009571ACN-122009571-A

Abstract

The invention discloses a cooperative control method of a range-extending engine power system of an unmanned aerial vehicle, which relates to the technical field of computer processing and comprises the following steps of obtaining the current flight altitude, the current flight speed, the current flight attitude angle and the battery residual capacity of the unmanned aerial vehicle in real time, and determining the output power of a motor and the recovery power of kinetic energy by combining the future altitude change trend in a preset flight plan; and determining a first power distribution duty ratio of the output power of the motor to the first power demand total amount according to the battery residual capacity and the future altitude change trend by a table look-up or optimization algorithm. The invention prejudges the evolution direction of the energy demand based on the flight plan prospectively, adjusts the weight of motor output and kinetic energy recovery in advance, and realizes the dynamic pre-compensation of power distribution.

Inventors

HUANG XINGRUI
ZENG SHUAI
LIANG CHENGJIE
YANG ZHUO
Shao Furong
ZHANG LEI
YAN RUYI
JIANG CHENGLIANG
CHEN KUN
CHEN ZHUOYING

Assignees

西南财经大学天府学院
四川引磁创新科技集团有限责任公司

Dates

Publication Date: 20260512
Application Date: 20260323

Claims (10)

1. The cooperative control method of the unmanned aerial vehicle range-extending engine power system is characterized by comprising the following steps of: Acquiring the current flight altitude, the current flight speed, the current flight attitude angle and the battery residual quantity of the real-time unmanned aerial vehicle, and determining the output power of a motor and the kinetic energy recovery power by combining the future altitude change trend in a preset flight plan; determining a first total power demand according to the current flight altitude, the current flight speed and the current flight attitude angle; Determining a first power distribution ratio of the output power of the motor to the total amount of the first power demand and a second power distribution ratio of the kinetic energy recovery power to the total amount of the first power demand through a table lookup or an optimization algorithm according to the residual battery power and the future altitude change trend; and calculating the output power of the motor and the kinetic energy recovery power according to the first power demand total amount, the first power distribution duty ratio and the second power distribution duty ratio.
2. The cooperative control method of a range-extending engine power system of an unmanned aerial vehicle according to claim 1, wherein a propeller of the unmanned aerial vehicle is mechanically connected with a kinetic energy recovery device, the kinetic energy recovery device comprises a variable pitch propeller and a generator, the propeller is in a windmill state under a specific working condition by adjusting the pitch angle of the propeller, and the generator is driven to generate electricity and store the electricity into a battery pack; The value of the first power distribution duty ratio is larger than 60% and smaller than 80%, the value of the second power distribution duty ratio is larger than 20% and smaller than 40%, and the first power distribution duty ratio and the second power distribution duty ratio are dynamically corrected according to flying height and flying speed.
3. The unmanned aerial vehicle range-extending engine power system cooperative control method of claim 1, further comprising the steps of: When the unmanned aerial vehicle is in the first flight working condition, acquiring terminal voltage of the battery pack in real time; If the terminal voltage is not in the first voltage range and the duration exceeds a first preset time threshold, keeping the output time period and the kinetic energy recovery time period of the motor unchanged during the next power distribution, determining an adjustment coefficient according to the amplitude of the terminal voltage deviating from the first voltage range, and adjusting the first power distribution duty ratio and the second power distribution duty ratio or the first power demand total amount according to the adjustment coefficient on the basis of unchanged first power demand total amount; If the terminal voltage is greater than the maximum value of the first voltage range, keeping the output time period and the kinetic energy recovery time period of the motor unchanged in the next power distribution, judging whether the first power distribution ratio which is determined at this time is less than A% in a first preset proportion range or not, and judging whether the second power distribution ratio which is determined at this time is less than B% in a second preset proportion range or not; If the first power distribution duty ratio determined at this time is subtracted by A% and the second power distribution duty ratio determined at this time is added by B% and is within the second preset proportion range, adjusting the output power duty ratio of the next motor = the first power distribution duty ratio determined at this time is subtracted by A%, and adjusting the power duty ratio of the next kinetic energy recovery = the second power distribution duty ratio determined at this time is added by B%; the values of A% and B% are determined linearly or nonlinearly according to the amplitude of the terminal voltage exceeding the maximum value of the first voltage range, and the larger the exceeding amplitude is, the larger the values of A% and B% are, and A and B are positive numbers larger than zero.
4. The cooperative control method of an extended-range engine power system of an unmanned aerial vehicle according to claim 3, wherein if the determined first power distribution ratio minus a% is not within the first preset proportion range and/or the determined second power distribution ratio plus B% is not within the second preset proportion range, it is determined whether the determined total amount of first power demand minus C is smaller than a first minimum limit power demand; If the current determined total first power demand minus C is greater than or equal to the first minimum limit power demand, adjusting the next total first power demand = current determined total first power demand minus C; if the determined first power demand total amount is less than the first minimum limit power demand by C, adjusting the next first power demand total amount = first minimum limit power demand; Wherein, the value of C is determined according to the boundary difference value between the first power distribution duty ratio determined at this time and the first preset proportion range, C is a first adjustment step of the first power demand total amount.
5. The cooperative control method of a range-extending engine power system of an unmanned aerial vehicle according to claim 3, wherein if the terminal voltage is smaller than a minimum value of the first voltage range, keeping the output time period of the motor and the kinetic energy recovery time period unchanged in the next power distribution, judging whether the first power distribution ratio plus d% determined at this time is within a first preset proportion range or not, and judging whether the second power distribution ratio minus e% determined at this time is within a second preset proportion range or not; If the first power distribution duty ratio determined at this time is added with D% and the second power distribution duty ratio determined at this time is subtracted by E% and is in the second preset proportion range, adjusting the output power duty ratio of the next motor = the first power distribution duty ratio determined at this time is added with D%, and adjusting the power duty ratio of the next kinetic energy recovery = the second power distribution duty ratio determined at this time is subtracted by E%; wherein, the values of D% and E% are determined linearly or nonlinearly according to the amplitude of the terminal voltage smaller than the minimum value of the first voltage range, the larger the amplitude is, the larger the values of D% and E% are, and D and E are positive numbers larger than zero.
6. The cooperative control method of an extended range engine power system of an unmanned aerial vehicle according to claim 5, wherein if the first power distribution ratio determined at this time plus D% is not within the first preset ratio range and/or the second power distribution ratio determined at this time minus E% is not within the second preset ratio range, determining whether the total amount of first power demand plus F determined at this time is greater than a first maximum limit power demand; If the sum of the first power demands determined at this time plus F is greater than or equal to the first maximum limit power demand, adjusting the next first power demand sum=the first maximum limit power demand; If the total amount of the first power demand determined at this time plus F is smaller than the first maximum limit power demand, adjusting the total amount of the first power demand of the next time = the total amount of the first power demand determined at this time plus F; And F is a second adjusting step length of the total quantity of the first power demand, wherein the value of F is determined according to the boundary difference value between the second power distribution duty ratio determined at this time and a second preset proportion range.
7. The cooperative control method of a range-extending engine power system of an unmanned aerial vehicle according to claim 2, wherein when the unmanned aerial vehicle is in a second flight condition, a second power demand total amount for supplying power to a motor is determined according to the combination of the flight height and the flight speed of the unmanned aerial vehicle, and a power supply time period of the motor is determined according to the flight speed, the battery residual capacity and the current environment temperature; Supplying the electric energy of the second power demand total amount to the motor in the power supply time period; and when the flying height of the unmanned aerial vehicle is smaller than a preset height threshold value and the flying speed is larger than a preset speed threshold value, the unmanned aerial vehicle is under the second flying working condition.
8. The unmanned aerial vehicle range-extending engine power system cooperative control method of claim 7, further comprising the steps of: When the unmanned aerial vehicle is in the second flight working condition, acquiring the terminal voltage of the battery pack in real time; Judging whether the terminal voltage is in a second voltage range or not; if the terminal voltage is not in the second voltage range and the duration exceeds a second preset time threshold, keeping the power supply time period unchanged when power is supplied next time, determining an adjusting coefficient according to the amplitude of the terminal voltage deviating from the second voltage range, and adjusting the total amount of the second power demand according to the adjusting coefficient.
9. The cooperative control method of a range-extending engine power system of an unmanned aerial vehicle according to claim 8, wherein if the terminal voltage is greater than the maximum value of the second voltage range, the power supply time period is kept unchanged when power is supplied next time, and whether the determined total amount of the second power demand minus G is smaller than a second minimum limit power demand is judged; If the determined total amount of the second power demand is less than or equal to the second minimum limit power demand, adjusting the next total amount of the second power demand = the determined total amount of the second power demand less than or equal to the determined total amount of the second power demand; if the determined total amount of the second power demand is less than the second minimum limit power demand, adjusting the next total amount of the second power demand = the second minimum limit power demand; And G is a first regulating step length of the total amount of the second power demand, and the value of G is determined according to the amplitude of the terminal voltage exceeding the maximum value of the second voltage range.
10. The cooperative control method of an extended range engine power system of an unmanned aerial vehicle according to claim 8, wherein if the terminal voltage is smaller than a minimum value of the second voltage range, the power supply time period is kept unchanged when power is supplied next time, and whether the determined total amount of the second power demand plus H is larger than a second maximum limit power demand is determined; if the total amount of the second power demand determined at this time plus H is larger than or equal to the second maximum limit power demand, the total amount of the second power demand at the next time = the second maximum limit power demand; And H is a second adjusting step length of the second power demand total amount, and the value of H is determined according to the amplitude that the terminal voltage is smaller than the minimum value of the second voltage range.

Description

Cooperative control method for power system of range-extended engine of unmanned aerial vehicle Technical Field The invention relates to the technical field of computer processing, in particular to a cooperative control method for a power system of an extended range engine of an unmanned aerial vehicle. Background With the vigorous development of low-altitude economy, unmanned aerial vehicles are increasingly widely applied to the fields of logistics transportation, emergency rescue, inspection and mapping and the like. The problem that the pure electric unmanned aerial vehicle is short in endurance time and weak in loading capacity is generally limited by the energy density bottleneck of the current lithium battery, and the high-strength task with long endurance and large load is difficult to be qualified. In order to solve the contradiction, the hybrid power system of the range-extending type of the oil and electricity becomes an important technical direction, and a hybrid power supply mode is formed by an internal combustion engine-generator combination and a battery pack, so that the requirements of high energy consumption of vertical take-off and landing and the requirements of cruising are considered. In the extended range hybrid system, the merits of the Energy Management Strategy (EMS) directly affect the endurance and flight safety of the unmanned aerial vehicle. The prior researches show that the fuel consumption can be effectively reduced and the mileage anxiety can be relieved by optimizing the power distribution among different power sources. For example, some studies have proposed an automatic throttle control strategy based on battery voltage feedback to stabilize battery state of charge around a preset value and to supplement the battery with redundant power during cruising. In addition, for the technology of recovering kinetic energy (i.e. regenerative braking) in the processes of descending, decelerating or posture adjustment of the unmanned aerial vehicle, the energy conversion principle and actual measurement efficiency of the unmanned aerial vehicle have been discussed in the prior literature, and it is pointed out that in an idealized hover-descending cycle test, the regenerative braking can improve the endurance by about 12.5%, and control strategies such as torque optimization distribution, intelligent working condition recognition and the like are provided. However, the prior art still has the following disadvantages: First, most energy management strategies distribute power based only on current transient parameters (e.g., instantaneous voltage, current load), lacking a prospective prediction of future flight trends. The power requirements of the unmanned aerial vehicle in different stages of climbing, cruising, descending and the like are obviously different, if the altitude change trend cannot be prejudged in advance and the energy flow direction is correspondingly adjusted, the battery is easy to overcharge and overdischarge or the power response is easy to lag. Secondly, the existing kinetic energy recovery control strategy only focuses on the energy recovery efficiency, and neglects the fine constraint on the engine rotating speed adjusting process. Studies have shown that the rotational speed switching behaviour of turboshaft engines must meet residence time constraints (DTCs), i.e. the minimum and maximum time that the engine must sustain at a certain operating mode or rotational speed, which is critical to ensuring safe operation of the engine. If this constraint is ignored in the energy recovery process, frequent switching of the engine working conditions may be caused, and unstable and even failure of the system may be caused. Third, in terms of voltage feedback adjustment, existing solutions generally employ simple proportional adjustment or fixed step adjustment, lacking a mechanism for adaptively determining an adjustment coefficient according to the voltage deviation amplitude. Meanwhile, most control strategies do not set duration time threshold values, so that misoperation is easy to occur due to instantaneous voltage fluctuation, and control robustness is affected. Fourth, for the hardware implementation scheme of multi-motor cooperation and energy feedback, some kinetic energy recovery devices are proposed in the prior art, such as the stator position is adjusted through a hydraulic telescopic rod to realize power generation, but the system design of the propeller pitch control and the cooperative adjustment of the generator is lacking, so that the optimal energy recovery efficiency and flight stability are difficult to realize in the whole flight envelope. In view of the foregoing, there is a need for a cooperative control method of an extended range engine power system of an unmanned aerial vehicle, which can integrate the prediction of flight trend, consider the constraint of engine speed, and have the capability of self-adapting voltage feedback adjustment, so