A low-altitude aircraft distributed battery pack power dynamic optimization management method and system

Abstract

The application provides a low-altitude aircraft distributed battery pack power dynamic optimization management method and system, which is applied to a low-altitude aircraft with multiple parallel battery packs, and each battery pack is connected with one or more motors. The method comprises the following steps: obtaining the operating parameters of each single battery in the battery pack of the low-altitude aircraft under the operating condition; calculating the power state of the battery pack by using the operating parameters, and adjusting the operating state of the low-altitude aircraft according to the support condition of the operating condition to optimize the power consumption; the operating state comprises the operating state of the motor; for the adjusted low-altitude aircraft, judging whether the battery pack reaches the balanced state according to the power state of the battery pack, if not, adopting an active balancing strategy to perform battery balancing treatment on the battery pack to optimize the state of the battery pack. Through the adjustment of the flight state under different operating conditions and the active balancing of the battery pack, the overall capacity and service life of the battery can be optimized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aircraft, and particularly relates to a low-altitude aircraft distributed battery pack power dynamic optimization management method and system. BACKGROUND

[0002] With the rapid development of science and technology, low-altitude aircraft have been widely used in many fields. They not only play a key role in public service fields such as disaster relief, surveying and mapping, but also penetrate into civilian fields such as off-road aerial photography and lighting pathfinding, providing great convenience for people's production and life and social development.

[0003] However, while low-altitude aircraft technology is constantly advancing, it also faces many challenges. In the low-altitude aircraft with multi-rotor structure, the design and management of battery packs become one of the key factors affecting their performance. Due to the production process limitations of the battery itself, the single cells in the assembled battery pack have differences in electrical performance, i.e., the uniformity is inconsistent. During use, the continuous charging and discharging cycles will cause the voltage difference between the single cells to gradually increase. This imbalance seriously affects the charging and discharging performance of the entire battery pack, and thus has a very adverse effect on the overall capacity and service life of the battery. In addition, when using a distributed battery pack design in a multi-rotor structure, even if the initial intention is to optimize power distribution, different use conditions will still cause the power of each battery pack to be inconsistent. For example, when performing different tasks or in different flight attitudes, the load difference of each motor and the change of environmental factors will cause the power imbalance between the battery packs. This inconsistency in power directly leads to a significant reduction in the endurance time and cruising range of the aircraft, greatly limiting the operating range and application scenarios of low-altitude aircraft.

[0004] Currently, although the power management technology for battery packs has developed to some extent, there are still obvious defects. Most of the existing technologies only balance the cells in the entire battery pack and each battery pack, and most of them use passive balancing technology. Although active balancing technology can theoretically transfer the energy from the high-energy part of the cell to the low-energy part of the cell, thus effectively balancing the energy difference between the cells, ensuring the consistency of the cells and improving the throughput of energy, in actual application, the design of active balancing circuit is extremely complex, and the layout of matrix switch is also quite complicated. Not only does it need to frequently switch the balancing circuit, but its reliability is difficult to effectively guarantee, making the entire system too complex and not conducive to precise control. Moreover, due to the coupling of the low-altitude aircraft system itself and the complex problems such as the difference in battery characteristics, the research and application of the separated battery pack and battery pack power dynamic optimization technology are still relatively few, which is difficult to meet the growing efficiency and precision needs of battery management in the actual use of low-altitude aircraft. SUMMARY

[0005] Therefore, the application provides a low-altitude aircraft distributed battery pack power dynamic optimization management method and system, aiming at the problem that the inconsistency of battery pack battery capacity affects the performance of aircraft battery charging and discharging, and further leads to poor endurance of unmanned aerial vehicles, small operation range, and affected overall capacity and service life of the battery, etc.

[0006] In order to achieve the above purpose, the technical scheme provided by the application is as follows:

[0007] In a first aspect, the application provides a low-altitude aircraft distributed battery pack power dynamic optimization management method, applied to a low-altitude aircraft with multiple parallel battery packs, each battery pack connected to one or more motors, comprising the following steps:

[0008] Obtain the operating parameters of each single battery in the battery pack of the low-altitude aircraft under the operating condition;

[0009] Calculate the power state of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft according to the support of the operating condition to optimize power consumption; the operating state includes the operating state of the motor;

[0010] For the adjusted low-altitude aircraft, determine whether the battery pack reaches an equilibrium state according to the power state of the battery pack, if not, use an active balancing strategy to balance the battery pack to optimize the state of the battery pack.

[0011] Further, the operating condition includes a take-off condition;

[0012] Under the take-off condition, calculate the power state of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft according to the support of the operating condition to optimize power consumption, including:

[0013] Calculate the remaining power of the battery pack using the operating parameters of the battery, and determine the maximum power currently available from the battery pack according to the remaining power;

[0014] Calculate the take-off power required by the low-altitude aircraft under the take-off condition according to the design parameters of the low-altitude aircraft;

[0015] Determine whether the maximum power currently available from the battery pack is greater than the take-off power, if yes, allow take-off operation and determine the power distribution ratio of the associated motor according to the remaining power ratio of the battery pack; if not, limit the take-off operation.

[0016] Further, the operating condition also includes a cruising condition;

[0017] During cruise operation, the battery pack's state of charge is calculated using operating parameters, and the low-altitude aircraft's operating status is adjusted based on the support provided by the state of charge for the current operating condition, in order to optimize power consumption, including:

[0018] Calculate the stable power required for low-altitude aircraft to cruise based on the flight parameters of the low-altitude aircraft;

[0019] Calculate the remaining battery capacity using the battery's operating parameters;

[0020] Calculate the remaining battery life based on the remaining battery power and stable power;

[0021] Determine whether the safety requirements are met based on the remaining flight time. If not, adjust the flight parameters of the low-altitude aircraft and calculate a new stable power until the remaining flight time of the adjusted low-altitude aircraft meets the safety requirements.

[0022] Furthermore, the operating conditions also include landing conditions;

[0023] During landing, the battery pack's state of charge is calculated using operating parameters, and the low-altitude aircraft's operating status is adjusted based on the support provided by the state of charge for the current operating condition to optimize power consumption, including:

[0024] Calculate the remaining battery capacity using the battery's operating parameters;

[0025] Calculate the auxiliary power required for a low-altitude aircraft during landing;

[0026] Determine whether the landing requirements are met based on the remaining battery power, auxiliary power, and landing time. If not, adjust the flight parameters of the low-altitude aircraft to reduce power consumption or change the landing location.

[0027] Furthermore, the state of charge of the battery pack includes the state of charge and the state of voltage; the state of charge and the state of voltage are determined based on the corrected integral values ​​of current and voltage, respectively, as follows:

[0028]

[0029]

[0030] In the formula, For a moment The amount of electricity, This is the initial charge level. From the initial time to the current time The number of time steps divided, The error coefficient, In order to time step The current value obtained by measurement at that time, is a time step; is a time is a corrected voltage, is a time is a voltage, is a temperature compensation coefficient, is a time is a discharge current, is a battery internal resistance.

[0031] Further, the battery pack is determined to reach the equalization state according to the state of charge of the battery pack, including:

[0032] The difference between the state of charge and the voltage of any two battery packs is determined to be less than a set threshold value, if yes, it is determined to reach the equalization state, if no, it is determined that the two battery packs do not reach the equalization state and need to be balanced according to the active equalization strategy.

[0033] Further, in the active equalization strategy, the equalization processing according to the active equalization strategy includes:

[0034] The corresponding motor is selected according to the remaining capacity of the battery pack from large to small, so as to reduce the capacity of the large-capacity battery pack;

[0035] Or energy conversion is carried out between the battery packs to reduce the capacity difference between the battery packs.

[0036] In a second aspect, the application provides a low-altitude aircraft distributed battery pack capacity dynamic optimization management system, including: a flight control system and a battery management system;

[0037] A plurality of parallel battery packs are arranged in the battery management system, and a plurality of motors are arranged in the flight control system; each battery pack is connected to one or more motors;

[0038] The battery management system is used to obtain the operating parameters of each single battery in the battery pack of the low-altitude aircraft under the operating condition; and is also used to calculate the capacity state of the battery pack by using the operating parameters, and to adjust the operating state of the low-altitude aircraft through the flight control system according to the support of the operating condition according to the capacity state, so as to optimize the capacity consumption; the operating state includes the operating state of the motor; and is also used for the low-altitude aircraft after adjustment, to determine whether the battery pack reaches the equalization state according to the capacity state of the battery pack, if no, to use the active equalization strategy to balance the battery pack, so as to optimize the state of the battery pack.

[0039] Further, the capacity state of the battery pack includes the state of charge and the voltage state of the battery pack; the state of charge and the voltage state are determined according to the corrected current integral value and the voltage integral value, respectively, as follows:

[0040]

[0041]

[0042] In the formula, is the power at time , is the initial power, is the number of time steps from the initial time to the current time , is the error coefficient, is the current value measured at time step , is the time step; is the corrected voltage at time , is the voltage at time , is the temperature compensation coefficient, is the discharge current at time , is the internal resistance of the battery.

[0043] Further, according to the state of charge of the battery pack, it is determined whether the battery pack reaches the balanced state, including:

[0044] It is determined whether the difference between the state of charge and the voltage of any two battery packs is less than a set threshold value, if yes, it is determined that the balanced state is reached, if not, it is determined that the balance between the two battery packs is not reached, and the balance processing needs to be carried out according to the active balancing strategy.

[0045] In summary, the present application provides a kind of low-altitude aircraft distributed battery pack power dynamic optimization management method and system, it is applied to the low-altitude aircraft with multiple parallel battery packs, and each battery pack is connected with one or more motors.Case of inclusion acquisition low-altitude aircraft in the operating condition under the battery pack the operating parameter of each single battery in battery pack;The state of charge of battery pack is calculated using operating parameter, and the support condition of operating condition is adjusted according to the state of charge of low-altitude aircraft operating state, to optimize power consumption;Operating state includes the operating state of motor;For the low-altitude aircraft after adjustment, according to the state of charge of battery pack, it is determined whether the battery pack reaches the balanced state, if not, battery balancing processing is carried out to the battery pack using active balancing strategy, to optimize the state of battery pack.The present application can solve the problems such as poor endurance, small operation range and affected overall capacity and service life of battery by adjusting the flight state under different operating conditions and actively balancing the battery pack. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0047] Figure 1 A flow chart of a low-altitude aircraft distributed battery pack power dynamic optimization management method provided by the embodiment of the present application;

[0048] Figure 2 A battery pack power optimization schematic diagram provided by the embodiment of the present application;

[0049] Figure 3 A battery pack power optimization method flow chart in a cruising state provided by the embodiment of the present application;

[0050] Figure 4 A composition block diagram of a low-altitude aircraft distributed battery pack power dynamic optimization management system provided by the embodiment of the present application. DETAILED DESCRIPTION

[0051] In order to make the purpose, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings of the embodiments of the present application. Obviously, the following described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0052] Please refer to Figure 1 The embodiment provides a low-altitude aircraft distributed battery pack power dynamic optimization management method, which is applied to a low-altitude aircraft with multiple parallel battery packs, each battery pack is connected with one or more motors, and includes the following steps.

[0053] S11: Obtain the operating parameters of each single battery in the battery pack of the low-altitude aircraft in the operating condition.

[0054] It should be noted that obtaining the operating parameters of each single battery in the battery pack of the low-altitude aircraft in the operating condition is the basis of the whole power dynamic optimization management. These operating parameters contain the current key information of the battery, such as the voltage, current and temperature of the battery single, etc. In different operating conditions (such as take-off, cruising, landing, etc.), the working state of the battery is different, and through collecting these parameters, data support can be provided for subsequent accurate analysis of the power condition and overall performance of the battery pack.

[0055] S12: Calculate the state of charge of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft according to the support of the operating condition to optimize the consumption of electricity; the operating state includes the operating state of the motor.

[0056] It should be noted that after obtaining the operating parameters of each single battery, one of the core steps is to calculate the state of charge of the battery pack using these parameters. Accurate grasp of the state of charge is crucial for reasonable control of the aircraft operation, which can reflect the current remaining power of the battery pack. Then, according to the support of the operating condition, the operating state of the low-altitude aircraft is adjusted, aiming to optimize the consumption of electricity, ensure that the aircraft can run efficiently and stably under different conditions, and avoid wasting electricity or affecting flight safety, performance, etc. due to insufficient electricity. The operating state of the motor is included in the operating state category because the motor is the main component that consumes battery power, and adjusting the working condition of the motor (such as power distribution, opening and closing, etc.) can directly affect the consumption rate of electricity.

[0057] S13: For the adjusted low-altitude aircraft, determine whether the battery pack reaches the balanced state according to the state of charge of the battery pack, if not, use the active balancing strategy to balance the battery pack to optimize the state of the battery pack.

[0058] It should be noted that after adjusting the operating state of the aircraft, it is an important step to ensure the overall performance of the battery pack and the subsequent continuous and stable operation of the aircraft to determine whether the battery pack reaches the balanced state according to the state of charge of the battery pack. Due to the influence of factors such as the characteristics of the battery itself and the working condition, the state of charge of each battery in the battery pack may be unbalanced. An unbalanced battery pack not only affects the overall charging and discharging performance and service life of the battery, but also may cause problems such as unstable power of the aircraft. If it is determined that the battery pack does not reach the balanced state, the active balancing strategy is used to balance the battery pack, which can make the state of charge of each battery consistent, optimize the state of the battery pack, improve the overall consistency and stability of the battery pack, and ensure that the battery can provide power for the motor and other components continuously and stably during the subsequent operation of the aircraft.

[0059] The embodiment provides a low-altitude aircraft distributed battery pack power dynamic optimization management method, first, accurate acquisition of the operating parameters of each single battery in the battery pack of the low-altitude aircraft under different operating conditions, accurate calculation of the battery pack power state on the basis, dynamic adjustment of the operating state of the low-altitude aircraft including the motor operating state according to the support condition of the power state, optimization of power consumption, and then judgment of whether the battery pack is balanced according to the power state of the adjusted battery pack, if not, the active balancing strategy is implemented to process the battery pack, through the series of steps from fine parameter monitoring, accurate power evaluation, flexible flight control to effective battery balancing, the problems of extensive battery management, complex and inefficient active balancing and insufficient power dynamic optimization in the prior art are solved, and efficient dynamic optimization management of the battery pack power of the low-altitude aircraft is realized.

[0060] The embodiment optimizes the flight state based on the battery power state under different conditions, avoids unnecessary power waste, and makes the battery power more reasonably utilized. The active balancing strategy is used for balancing the battery pack, which can timely correct the power imbalance of each single battery in the battery pack, avoid damage to the overall capacity of the battery caused by excessive charging and discharging of part of the battery, and ensure the health state of the battery during use. Meanwhile, the management method starts from obtaining the operating parameters of the single battery, accurately calculates the power state, dynamically adjusts the flight state and performs the battery balancing treatment, forms a perfect and fine management process, overcomes the problem of inaccurate and inefficient battery management in the prior art, meets the growing efficiency and accuracy requirements of battery management in the actual use of the low-altitude aircraft, ensures the stability and reliability of the aircraft flight, and improves the overall performance and use value of the low-altitude aircraft.

[0061] In one embodiment, the power state of the battery pack includes the state of charge and the voltage state of the battery pack; the state of charge and the voltage state are determined according to the corrected current integral value and the voltage integral value respectively. The current integral value and the voltage integral value are calculated by using a high-precision current integral algorithm and a high-precision voltage compensation algorithm respectively, and the steps are as follows:

[0062] (1) High-precision current integral algorithm

[0063] 1) Current measurement

[0064] First, the charging and discharging current of the battery pack is measured in real time by a high-precision current sensor. Let the measured current value be I, and its unit is ampere (A), where I represents the measured current value. represents time.

[0065] For example, the accuracy of the current sensor can reach ±0.1%, which can accurately capture the slight change of the current.

[0066] 2) Integral calculation

[0067] To calculate the remaining capacity (SOC) of the battery, the current needs to be integrated. Using a discrete-time integration method, the time interval is divided into small steps .

[0068] At each time step, the integral of the current with respect to time is accumulated. Let be the capacity of the battery (unit: ampere-hour, Ah), and the initial capacity is , then the integral formula is:

[0069]

[0070] where is the number of time steps divided from the initial time to the current time .

[0071] 3) Error correction

[0072] Due to the zero drift and measurement error of the current sensor, error correction is needed. Regular calibration of the battery can be performed, for example, when the battery is in a stationary state and the initial capacity is known, the integral value of the current over a period of time is measured and compared with the actual capacity that should remain unchanged, to determine the error coefficient . The corrected current integral formula becomes:

[0073]

[0074] where is the error coefficient, is the current value measured at time step .

[0075] (2) High-precision voltage compensation algorithm

[0076] 1) Voltage measurement

[0077] Use a high-precision voltage sensor to measure the terminal voltage of the battery monomer , with an accuracy of ±0.01V.

[0078] 2) Temperature compensation

[0079] The voltage of the battery is closely related to the temperature. Let the temperature of the battery be , according to the temperature characteristic curve of the battery, the influence coefficient of temperature on voltage is obtained. Then the compensated voltage is:

[0080]

[0081] For example, in lithium-ion batteries, the open-circuit voltage decreases as the temperature rises. Temperature compensation can more accurately reflect the true state of the battery.

[0082] 3) Load compensation

[0083] When the battery is in a discharging state, due to the battery's internal resistance The presence of [something] will cause a voltage drop. Let the discharge current be [something]. The voltage drop caused by the load is The compensated voltage formula becomes:

[0084]

[0085] Similarly, during the charging process, it is also necessary to consider and compensate for the voltage changes caused by the charging current.

[0086] In a further embodiment, determining whether the battery pack has reached an equilibrium state based on the battery pack's state of charge includes:

[0087] Determine whether the difference in state of charge and voltage between any two battery packs is less than a set threshold. If so, it is determined that the battery packs have reached a balanced state. If not, it is determined that the two battery packs have not reached a balanced state and need to be balanced according to the active balancing strategy.

[0088] The following sections will introduce how to determine the difference in state of charge and the difference in voltage.

[0089] (1) SOC difference judgment

[0090] Calculate the SOC of each individual cell in the battery pack, assuming the first... The SOC of each battery cell is When the SOC difference between any two battery cells Greater than the set threshold (For example When this occurs, the equilibrium condition is triggered. That is... This indicates that the SOC imbalance between individual battery cells exceeds the acceptable range and requires balancing.

[0091] (2) In addition to SOC differences, the equalization condition can also be determined based on the voltage differences of individual battery cells. Let the first... The voltage of each battery cell is When the voltage difference between any two battery cells Greater than the set voltage threshold (For example When this happens, the equilibrium condition is also triggered. That is... , indicating that the voltage between the battery monomers is not balanced, which may affect the overall performance and life of the battery pack, and needs to be balanced and adjusted.

[0092] In further embodiments, in the active balancing strategy, the balancing process according to the active balancing strategy includes: selecting the corresponding motor according to the remaining power of the battery pack from large to small to reduce the power of the large-capacity battery pack; or converting energy between the battery packs to reduce the power difference between the battery packs.

[0093] When active balancing is performed, first, at a certain sampling frequency (e.g. ) simultaneously collect the current , voltage and temperature and other data of the battery pack.

[0094] Then calculate the SOC of the battery according to the high-precision current integration algorithm, and compensate the battery monomer voltage according to the high-precision voltage compensation algorithm. Then determine whether the balancing condition is met.

[0095] If the SOC or voltage imbalance condition is met, enter the balancing control phase; if not, continue to monitor the battery state, and control the charging and discharging process of the battery according to the SOC and other state information of the battery. For example, when the SOC is close to 100%, reduce the charging current to prevent overcharging; when the SOC is low, reasonably distribute the discharging current according to the load demand to prolong the service life of the battery.

[0096] When the balancing condition is triggered, operate according to the balancing strategy adopted by the battery management system. If it is an active balancing strategy, transfer the energy of the battery monomer with higher power to the battery monomer with lower power through a bidirectional DC-DC converter. Let the transferred power be , the transfer time is , then the transferred power is . By reasonably controlling the transfer power and time, gradually reduce the SOC or voltage difference between the battery monomers.

[0097] If it is a passive balancing strategy, parallel resistors are connected to the battery monomer with higher power to make it discharge extra until the difference between the battery monomers is reduced to within the threshold range.

[0098] Throughout the control process, feedback adjustments are made based on the actual operating state of the battery. For example, if the temperature of a certain battery cell rises too quickly during the balancing process, the balancing strategy or the balancing power may be adjusted to ensure the safe operation of the battery pack. At the same time, based on the long-term use data of the battery, the error coefficient in the current integration algorithm, the temperature and load influence coefficient in the voltage compensation algorithm, and other parameters are optimized to improve the accuracy and reliability of the battery management system.

[0099] Please refer to Figure 2 , Figure 2 A schematic diagram of a battery management system for battery pack power optimization is shown. The flight control system (Flight Control System) is located at the top of the diagram. The flight control system is connected to four motors (Motor, labeled M). The motor (Motor) is labeled M, and each motor is connected to a battery pack. There are four battery packs in total, labeled Battery Pack 1, Battery Pack 2, Battery Pack 3, and Battery Pack 4. Each battery pack is connected to a matrix switch. There are four matrix switches in total, located below each battery pack. Each matrix switch is connected to a bidirectional DC / DC converter. There are four bidirectional DC / DC converters in total, located below each matrix switch. These converters are connected to a DC bus. The battery management system (Battery Management System) is located on the left side of the diagram. The battery management system is connected to the four matrix switches. The following will be described in combination with Figure 2 The active balancing strategy of the above embodiment is introduced.

[0100] As Figure 2 shown, when the power of battery pack 1 and battery pack 4 is the largest, the flight control system can control the corresponding motors of battery pack 1 and battery pack 4 as the main power source to provide the main energy source, so that the battery power of battery pack 1, 2, 3, and 4 is close. At the same time, the battery management system can also start the active balancing mode. After the matrix switch is opened, the battery of battery pack 1 flows through the bidirectional DC / DC converter to battery pack 2, and so on, so that the battery power of battery pack 1, 2, 3, and 4 is consistent. The main function of this architecture is to control and manage the charging and discharging process of the battery pack through the battery management system to ensure that the motor can stably obtain power supply. The bidirectional DC / DC converter is used for electric energy conversion between the battery pack and the DC bus, and the matrix switch is used for selecting and controlling the connection state of the battery pack.

[0101] In the above battery pack power optimization process, through the adaptive battery energy allocation strategy, the energy supply proportion of each battery pack is dynamically adjusted according to the real-time demand of the flight task. For example, when the aircraft performs high-intensity maneuvering action, the energy is preferentially allocated to the battery pack corresponding to the motor that plays a key role in maneuverability, ensuring accurate control of flight attitude; while in the smooth cruising stage, the energy is evenly distributed or intelligently allocated according to the difference in battery pack power to achieve efficient utilization and power balance of the overall battery system.

[0102] The relatively sufficient battery pack is preferentially utilized to avoid the situation that some battery packs are over-discharged while other battery packs still have a lot of power left, which helps to make the power of each battery pack tend to be close as a whole. On this basis, combined with the active balancing mode of the battery management system, the flow of power between different battery packs is realized by using a bidirectional DC / DC converter, such as making the power of battery pack 1 flow to battery pack 2 and so on, which can more accurately ensure that the power of each battery pack is highly consistent. In this way, the available capacity of the entire battery system can be more fully utilized, prolonging the overall endurance time of the battery pack and improving the service life of the battery pack, as the problem of rapid performance degradation of the battery caused by overcharging and over-discharging of individual battery packs is avoided.

[0103] The battery management system and the flight control system cooperatively play a core control role in managing the charging and discharging process of the battery pack, selecting and controlling the connection state of the battery pack through the matrix switch, and converting electrical energy between the battery pack and the DC bus through the bidirectional DC / DC converter, so that the motor can stably obtain power supply under different flight conditions (such as different power demands at different stages of take-off, cruising, landing, etc.). For example, during flight, the main power source is flexibly switched according to the power of each battery pack, and through electrical energy conversion and power balancing adjustment, the stable output of electrical energy at the DC bus is ensured, avoiding fluctuations in motor power output caused by uneven battery pack power or poor electrical energy conversion, thereby improving the safety and reliability of the aircraft flight.

[0104] According to the different working modes of the aircraft (such as take-off, climbing, cruising, landing) and the real-time state of the energy (such as battery power, fuel remaining), the switching between battery and fuel generator and other energy sources is automatically and smoothly performed, and the collaborative work of the two is optimized. For example, during take-off and climbing, the battery and fuel generator are preferentially used to provide powerful power together to quickly raise the height of the aircraft; during cruising, the output power of the two is reasonably distributed according to the remaining battery power and fuel consumption to achieve the best energy utilization efficiency and endurance distance; during landing, stable power is mainly provided by the battery to ensure the safety and accuracy of the landing process.

[0105] In a further embodiment, the operating condition includes a take-off condition;

[0106] In the take-off condition, the state of charge of the battery pack is calculated using the operating parameters, and the operating state of the low-altitude aircraft is adjusted according to the support of the operating condition to optimize the consumption of the electric quantity, including:

[0107] S21: Calculate the remaining electric quantity of the battery pack using the operating parameters of the battery, and determine the maximum power that the battery pack can currently provide according to the remaining electric quantity.

[0108] It should be noted that at take-off, the current state information of the battery pack is first obtained from the battery management system through the flight control system of the aircraft, including the remaining electric quantity of the battery , the voltage and temperature of each battery cell, etc. The is calculated by a high-precision current integration algorithm, for example, the current . Then according to the remaining electric quantity, the maximum power that the battery pack can provide can be determined.

[0109] S22: Calculate the take-off power required by the low-altitude aircraft in the take-off condition according to the design parameters of the low-altitude aircraft.

[0110] It should be noted that the take-off power required is calculated according to the take-off weight , the acceleration required for take-off, and the aerodynamic parameters, etc. of the aircraft. Assuming that the thrust-power relationship of the aircraft is (where , , is the acceleration of gravity, and is the take-off speed).

[0111] S23: Determine whether the maximum power that the battery pack can currently provide is greater than the take-off power. If yes, allow take-off operation and determine the power distribution ratio of the associated motor according to the proportion of the remaining electric quantity of the battery pack; if no, limit the take-off operation.

[0112] It should be noted that whether the battery can provide enough power to meet the take-off requirement is evaluated by the battery management system of the aircraft according to the current battery state. If (Where is the maximum power that the battery pack can provide, which can be calculated according to the parameters such as the , voltage and internal resistance of the battery, for example , is the efficiency of the battery pack, is the total voltage of the battery pack, If the maximum discharge current is allowed, the take-off operation continues; otherwise, the operating state of the low-altitude aircraft is adjusted, for example, the flight control system issues a warning and limits the take-off.

[0113] In the take-off operating condition, battery balancing and power distribution adjustment are required. That is, during the take-off process, the battery state is continuously monitored. If there is a difference in SOC between battery monomers in the battery pack or a voltage difference (such as the balancing condition threshold described earlier), the battery management system starts the balancing operation.

[0114] For active balancing, the energy distribution between battery monomers is adjusted through a bidirectional DC-DC converter to ensure the stability of the overall performance of the battery pack. At the same time, according to the state of the battery monomers, the flight control system can adjust the power distribution of the motors. For example, if a certain battery monomer has a low voltage, the power distribution ratio of the motor associated with it is appropriately reduced , the total motor power is , the power of the th motor is , where is dynamically adjusted according to the voltage, SOC, etc. of the battery monomer to ensure the safety and stability of the overall flight.

[0115] In one embodiment, the operating condition further includes a cruising operating condition;

[0116] In the cruising operating condition, the state of charge of the battery pack is calculated using the operating parameters, and the operating state of the low-altitude aircraft is adjusted according to the support of the operating condition to optimize power consumption, including:

[0117] S31: Calculate the stable power required for the low-altitude aircraft to cruise according to the flight parameters of the low-altitude aircraft.

[0118] It should be noted that after entering the cruising stage, the stable power required for cruising is calculated according to the current flight height , flight speed , air resistance , etc. (for example ).

[0119] S32: Calculate the remaining power of the battery pack using the operating parameters of the battery.

[0120] It should be noted that the remaining power of the battery is accurately calculated by combining the high-precision current integration algorithm and the voltage compensation algorithm .

[0121] S33: Calculate the remaining endurance time according to the remaining power and the stable power.

[0122] It is noted that the remaining endurance time is estimated according to the remaining battery capacity and the cruising power (wherein is the remaining battery capacity calculated according to the SOC, = , is the rated capacity of the battery pack).

[0123] S34: Determine whether the safety requirement is met according to the remaining endurance time. If not, adjust the flight parameters of the low-altitude aircraft and calculate a new stable power until the remaining endurance time of the adjusted low-altitude aircraft meets the safety requirement.

[0124] It is noted that if the estimated endurance time is lower than the safety threshold , the flight control system will plan a return path or find a suitable landing site and adjust the flight parameters, such as reducing the flight speed to reduce power consumption, = ( calculated according to the remaining battery capacity and safety requirements), and accordingly recalculate and .

[0125] In the cruising working condition, battery state maintenance and balancing strategy optimization are needed. During cruising, the voltage and temperature changes of the battery cells are continuously monitored. Since the load is relatively stable during cruising, more attention is paid to the long-term health state maintenance of the battery. If the temperature of a certain battery cell is higher than the upper limit of the safe temperature , the flight control system and the battery management system cooperate to adjust the aircraft attitude or turn on the cooling device to reduce the battery temperature.

[0126] For the battery balancing strategy, under the premise of meeting the flight power demand, the frequency and energy transfer amount of active balancing are appropriately increased to further reduce the SOC and voltage differences between the battery cells and improve the overall consistency and life of the battery pack. For example, increasing the power transfer amount of active balancing causes the SOC difference between the battery cells to gradually decrease during cruising,

[0127] .

[0128] In one embodiment, the working condition further includes a landing working condition;

[0129] In the landing working condition, the state of charge of the battery pack is calculated using the operating parameters, and the operating state of the low-altitude aircraft is adjusted according to the support of the operating condition to optimize the power consumption, including:

[0130] S41: Calculate the remaining power of the battery pack using the operating parameters of the battery.

[0131] It should be noted that when the flight control system receives the landing instruction, it first obtains the remaining power of the battery from the battery management system and the voltage state of the battery pack.

[0132] S41: Calculate the auxiliary power required for the low-altitude aircraft during landing.

[0133] It should be noted that it is necessary to check whether the remaining power is sufficient to support various operations during the landing process, including the power requirements of auxiliary systems such as landing gear deployment, flap adjustment, etc. .

[0134] S41: Determine whether the landing requirements are met based on the remaining power and auxiliary power and the landing time, if not, adjust the flight parameters of the low-altitude aircraft to reduce power consumption or change the landing site.

[0135] It should be noted that if ( is the battery discharge efficiency, is the estimated landing time), the normal landing procedure is allowed. Otherwise, the flight control system will take emergency measures, such as prioritizing power supply for critical systems, reducing power consumption for non-critical systems, or attempting to land at a closer suitable location.

[0136] In the landing working condition, battery safety and fault handling need to be considered. During the landing process, the state of the battery pack is closely monitored. If a battery cell is over-discharged (the voltage is lower than the over-discharge threshold ) or other abnormal conditions occur, the flight control system will immediately take measures such as cutting off the circuit related to the abnormal battery cell, using the remaining healthy battery cells to complete the landing operation, and conducting a comprehensive inspection and fault diagnosis of the battery pack after landing. At the same time, record the battery state data during the landing process, including the change curves of SOC, voltage, temperature, etc., for subsequent analysis and optimization of battery management strategies, to improve the battery usage efficiency and flight safety of the aircraft in different working conditions.

[0137] Through close cooperation between the flight control system and the battery management system in different working conditions such as take-off, cruising and landing, comprehensive consideration of the power demand of the aircraft, battery state and flight safety and other factors, effective control and optimized operation of the aircraft are realized.

[0138] Please refer to Figure 3 , Figure 3 which shows the process of battery optimization management in cruising condition, including the following steps:

[0139] 1. Start the process.

[0140] 2. System sends instructions:

[0141] The system first sends instructions.

[0142] 3. Obtain battery pack state of charge, motor power state, power direction, etc.:

[0143] The system obtains the state of charge of each battery pack, the power state of the motor, and the power direction, etc.

[0144] 4. In cruise mode, whether the battery pack reaches the balanced state:

[0145] The system checks whether the battery pack reaches the balanced state in cruise mode. If it reaches the balanced state, the flow jumps to the "end" node. If it does not reach the balanced state, it continues to the next step.

[0146] 5. The maximum capacity battery pack charges the minimum capacity battery pack:

[0147] The system allows the maximum capacity battery pack to charge the minimum capacity battery pack.

[0148] 6. The maximum capacity battery pack mainly provides motor power energy:

[0149] The maximum capacity battery pack is mainly responsible for providing the required motor power energy.

[0150] 7. Flight control system controls aircraft balance:

[0151] The flight control system is responsible for controlling the balance of the aircraft.

[0152] 8. Whether the battery pack reaches the balanced state:

[0153] The system checks again whether the battery pack reaches the balanced state. If it reaches the balanced state, the flow jumps to the "end" node. If it does not reach the balanced state, the flow returns to step 5 and continues to charge and balance control operations.

[0154] 9. End:

[0155] When the battery pack reaches the balanced state, the flow ends.

[0156] In a conventional state, the battery management system sends instructions to obtain the state of charge of each battery pack, and obtains the battery power state, power direction, etc. from the flight control system. When the aircraft is flying in a cruising state, if the battery packs are in an unbalanced state, the maximum capacity battery pack charges the minimum capacity battery pack; when the SOC state difference between the battery packs is more than 5% or the SOC state of a certain battery pack is less than 30%, the system carries out the flight control balancing mode. During flight, the working condition of the motor is controlled to preferentially use the battery pack with high capacity to supply power, and at the same time, the approach system controls the balance of the aircraft.

[0157] Referring to Figure 4 , the embodiment of the present application also provides a low-altitude aircraft distributed battery pack capacity dynamic optimization management system, comprising: a flight control system and a battery management system;

[0158] A plurality of parallel battery packs are arranged in the battery management system, and a plurality of motors are arranged in the flight control system; each battery pack is connected to one or more motors;

[0159] The battery management system is used to obtain the operating parameters of each single battery in the battery pack of the low-altitude aircraft under the operating condition; is also used to calculate the capacity state of the battery pack by using the operating parameters, and according to the support condition of the operating condition, adjust the operating state of the low-altitude aircraft through the flight control system to optimize the capacity consumption; the operating state includes the operating state of the motor; is also used for judging whether the battery pack reaches a balanced state according to the capacity state of the battery pack for the adjusted low-altitude aircraft, if not, using an active balancing strategy to carry out battery balancing treatment on the battery pack to optimize the state of the battery pack.

[0160] Further, the capacity state of the battery pack includes the state of charge and the voltage state of the battery pack; the state of charge and the voltage state are determined according to the corrected current integral value and the voltage integral value respectively, as follows:

[0161]

[0162]

[0163] In the formula, is the capacity at time , is the initial capacity, is the number of time steps divided from the initial time to the current time , is an error coefficient, is the current value measured at time step , is the time step; is the corrected voltage at time , For a moment voltage, This is the temperature compensation coefficient. For a moment The discharge current, This represents the battery's internal resistance.

[0164] Furthermore, determining whether the battery pack has reached a balanced state based on its state of charge includes:

[0165] Determine whether the difference in state of charge and voltage between any two battery packs is less than a set threshold. If so, it is determined that the battery packs have reached a balanced state. If not, it is determined that the two battery packs have not reached a balanced state and need to be balanced according to the active balancing strategy.

[0166] Furthermore, the operating conditions include takeoff conditions;

[0167] During takeoff, the battery pack's state of charge is calculated using operating parameters, and the low-altitude aircraft's operating state is adjusted based on the support provided by the state of charge for the current operating condition to optimize power consumption, including:

[0168] The remaining battery charge is calculated using the battery's operating parameters, and the maximum power that the battery pack can currently provide is determined based on the remaining charge.

[0169] Calculate the required takeoff power of the low-altitude aircraft under takeoff conditions based on the design parameters of the low-altitude aircraft.

[0170] Determine if the maximum power currently available from the battery pack is greater than the takeoff power. If so, allow takeoff and determine the power allocation ratio of the associated motors according to the remaining charge percentage of the battery pack. If not, restrict takeoff.

[0171] Furthermore, the operating conditions also include cruise conditions;

[0172] During cruise operation, the battery pack's state of charge is calculated using operating parameters, and the low-altitude aircraft's operating status is adjusted based on the support provided by the state of charge for the current operating condition, in order to optimize power consumption, including:

[0173] Calculate the stable power required for low-altitude aircraft to cruise based on the flight parameters of the low-altitude aircraft;

[0174] Calculate the remaining battery capacity using the battery's operating parameters;

[0175] Calculate the remaining battery life based on the remaining battery power and stable power;

[0176] If the remaining endurance time does not meet the safety requirement, the flight parameters of the low-altitude aircraft are adjusted, and a new stable power is calculated until the remaining endurance time of the adjusted low-altitude aircraft meets the safety requirement.

[0177] Further, the operating condition further includes a landing condition.

[0178] In the landing condition, the state of charge of the battery pack is calculated by using the operating parameters, and the operating state of the low-altitude aircraft is adjusted according to the support of the operating condition to optimize the power consumption, including:

[0179] The remaining power of the battery pack is calculated by using the operating parameters of the battery.

[0180] The auxiliary power required by the low-altitude aircraft in the landing process is calculated.

[0181] Whether the landing requirement is met is judged according to the remaining power, the auxiliary power and the landing time, and if not, the flight parameters of the low-altitude aircraft are adjusted to reduce the power consumption or change the landing site.

[0182] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for dynamic optimization management of battery power distribution for low altitude aircraft, comprising: The application is applied to low-altitude aircraft with multiple groups of parallel battery packs, each group of battery packs is connected with one or more motors, and comprises the following steps: Obtaining the operating parameters of each single battery in the battery pack of the low-altitude aircraft under the operating condition; Using the operating parameters to calculate the state of charge of the battery pack, and adjusting the operating state of the low-altitude aircraft according to the support condition of the operating condition to optimize the power consumption; the operating state includes the operating state of the motor; For the adjusted low-altitude aircraft, judging whether the battery pack reaches the balanced state according to the state of charge of the battery pack, if not, using the active balancing strategy to perform battery balancing processing on the battery pack to optimize the state of the battery pack; The operating condition includes the take-off condition; In the take-off condition, using the operating parameters to calculate the state of charge of the battery pack, and adjusting the operating state of the low-altitude aircraft according to the support condition of the operating condition to optimize the power consumption, including: Using the operating parameters of the battery to calculate the remaining power of the battery pack, and determining the maximum power currently provided by the battery pack according to the remaining power; According to the design parameters of the low-altitude aircraft, calculating the take-off power required by the low-altitude aircraft in the take-off condition; Judging whether the maximum power currently provided by the battery pack is greater than the take-off power, if yes, allowing take-off operation and determining the power distribution ratio of the associated motor according to the remaining power ratio of the battery pack; if not, limiting the take-off operation; The operating condition also includes the cruising condition; In the cruising condition, using the operating parameters to calculate the state of charge of the battery pack, and adjusting the operating state of the low-altitude aircraft according to the support condition of the operating condition to optimize the power consumption, including: According to the flight parameters of the low-altitude aircraft, calculating the stable power required by the low-altitude aircraft for cruising; Using the operating parameters of the battery to calculate the remaining power of the battery pack; According to the remaining power and the stable power, calculating the remaining endurance time; According to the remaining endurance time, judging whether the safety requirement is met, if not, adjusting the flight parameters of the low-altitude aircraft and calculating the new stable power until the remaining endurance time of the adjusted low-altitude aircraft meets the safety requirement; The operating condition also includes the landing condition; In the landing condition, using the operating parameters to calculate the state of charge of the battery pack, and adjusting the operating state of the low-altitude aircraft according to the support condition of the operating condition to optimize the power consumption, including: Using the operating parameters of the battery to calculate the remaining power of the battery pack; Calculating the auxiliary power required by the low-altitude aircraft during landing; According to the remaining power, the auxiliary power, and the landing time, judging whether the landing requirement is met, if not, adjusting the flight parameters of the low-altitude aircraft to reduce power consumption or changing the landing site; The state of charge of the battery pack includes a state of charge and a voltage state of the battery pack; the state of charge and the voltage state are determined according to the corrected current integral value and the voltage integral value respectively, as follows: ； ； In the formula, is the power at time , is the initial power, is the number of time steps from the initial time to the current time , is the error coefficient, is the current value measured at time step , is the time step; is the voltage at time , is the voltage at time , is the temperature compensation coefficient, is the discharge current at time , is the battery internal resistance.

2. The method of claim 1, wherein, It is determined whether the battery pack reaches an equalization state according to the state of charge of the battery pack, including: It is determined whether the difference between the state of charge and the voltage of any two battery packs is less than a set threshold value, if yes, it is determined that the equalization state is reached, if not, it is determined that the equalization between the two battery packs is not reached, and the equalization treatment according to the active equalization strategy is needed.

3. The method of claim 1, wherein, In the active equalization strategy, the equalization treatment according to the active equalization strategy includes: The corresponding motor is selected according to the residual capacity of the battery pack from large to small, so as to reduce the capacity of the large-capacity battery pack; Or the energy conversion is carried out between the battery packs to reduce the capacity difference between the battery packs.

4. A low altitude vehicle distributed battery pack power dynamic optimization management system, characterized in that, A low-altitude aircraft distributed battery pack capacity dynamic optimization management method is realized based on the low-altitude aircraft distributed battery pack capacity dynamic optimization management method, including a flight control system and a battery management system; A plurality of parallel battery packs are arranged in the battery management system, and a plurality of motors are arranged in the flight control system; each battery pack is connected with one or more motors; The battery management system is used to obtain the operating parameters of each single battery in the battery pack under the operating condition of the low-altitude aircraft; and is also used to calculate the state of charge of the battery pack by using the operating parameters, and to adjust the operating state of the low-altitude aircraft through the flight control system according to the support condition of the operating condition under the state of charge, so as to optimize the capacity consumption; the operating state includes the operating state of the motor; and is also used to determine whether the battery pack reaches an equalization state according to the state of charge of the battery pack for the adjusted low-altitude aircraft, if not, the battery equalization treatment is carried out on the battery pack by using the active equalization strategy, so as to optimize the state of the battery pack.

5. The distributed battery pack power dynamic optimization management system for low altitude aerial vehicles of claim 4, wherein, The state of charge of the battery pack includes a state of charge and a voltage state of the battery pack; the state of charge and the voltage state are determined according to the corrected current integral value and the voltage integral value respectively, as follows: ； ； In the formula, is the power at time , is the initial power, is the number of time steps divided from the initial time to the current time , is the error coefficient, is the current value measured at time step , is the time step; is the voltage at time , is the voltage at time , is the temperature compensation coefficient, is the discharge current at time , is the battery internal resistance.

6. The low altitude vehicle distributed battery pack power dynamic optimization management system of claim 5, wherein, It is determined whether the battery pack reaches an equalization state according to the state of charge of the battery pack, including: It is determined whether the difference between the state of charge and the voltage of any two battery packs is less than a set threshold value, if yes, it is determined that the equalization state is reached, if not, it is determined that the equalization between the two battery packs is not reached, and the equalization treatment according to the active equalization strategy is needed.

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