Dynamic optimization management method and system for electric quantity of distributed battery pack of low-altitude aircraft

Abstract

The invention provides a low-altitude aircraft distributed battery pack electric quantity dynamic optimization management method and system which are applied to a low-altitude aircraft with a plurality of battery packs connected in parallel, and each battery pack is connected with one or more motors. Comprising the following steps: acquiring operation parameters of each single battery in a battery pack of the low-altitude aircraft under an operation condition; the electric quantity state of the battery pack is calculated through the operation parameters, and the operation state of the low-altitude aircraft is adjusted according to the supporting condition of the electric quantity state on the operation working condition, so that electric quantity consumption is optimized; the operation state comprises the operation state of the motor; and for the adjusted low-altitude aircraft, judging whether the battery pack reaches an equalization state according to the electric quantity state of the battery pack, and if not, performing battery equalization processing on the battery pack by adopting an active equalization strategy to optimize the state of the battery pack. According to the invention, through adjustment of the flight state and active equalization of the battery pack under different operation conditions, the overall capacity and the service life of the battery can be optimized.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft, and in particular relates to a method and system for dynamically optimizing the management of power levels of distributed battery packs of low-altitude aircraft. Background Art

[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 services such as disaster relief and surveying, but also penetrate into civilian fields such as off-road aerial photography and lighting and pathfinding, providing great convenience for people's production and life and social development.

[0003] However, while low-altitude aircraft technology continues to advance, it also faces many challenges. In low-altitude aircraft with multi-rotor structures, the design and management of battery packs have become one of the key factors affecting their performance. Due to the limitations of the battery's own production process, there are differences in the electrical properties of the assembled single cells, that is, the uniformity is inconsistent. During use, continuous charge and discharge cycles will cause the voltage gap of the single cells to gradually increase. This imbalance seriously affects the charge and discharge performance of the entire battery group, and thus has an extremely adverse effect on the overall capacity and service life of the battery. In addition, when a distributed battery pack design is adopted in a multi-rotor structure, even if the original intention is to optimize power distribution, different operating conditions will still cause inconsistencies in the power of each battery pack. For example, when performing different tasks or in different flight postures, the load differences of each motor and changes in environmental factors will cause an imbalance in the power between battery packs. This power inconsistency directly leads to a significant reduction in the aircraft's flight time and a significant reduction in the cruising range, which greatly limits the operating range and application scenarios of low-altitude aircraft.

[0004] At present, although the power management technology for battery packs has made some progress, it still has obvious defects. Most of the existing technologies only balance the cells of the entire battery pack and each battery pack, and most of them use passive balancing technology. Although active balancing technology can theoretically discharge the high-energy part of the cell to the low-energy cell, thereby effectively balancing the energy difference between the cells, ensuring the consistency of the cells, and improving the energy throughput, in practical applications, the design of active balancing circuits is extremely complex, and the layout of matrix switches is also quite cumbersome. This not only requires frequent switching of the balancing circuit, but also its reliability is difficult to be effectively guaranteed, making the entire system too complex and not conducive to precise control. In addition, due to the complex problems such as the coupling of the low-altitude aircraft system itself and the differences in battery characteristics, there are relatively few studies and applications on the dynamic optimization technology of separate battery packs and battery packs, which is difficult to meet the growing demand for efficiency and accuracy of battery management in the actual use of low-altitude aircraft. Summary of the invention

[0005] In view of this, the present invention proposes a method and system for dynamically optimizing the power management of distributed battery packs for low-altitude aircraft, aiming to address the problems in the above-mentioned prior art where the inconsistency of battery pack capacity affects the charging and discharging performance of the aircraft battery, thereby leading to poor UAV endurance, small operating range, and affected overall battery capacity and service life. By controlling the motor state and optimizing the battery pack power management method through the flight control system, the battery capacity of the shortboard battery pack is improved, thereby improving the cruising range of the low-altitude aircraft.

[0006] In order to achieve the above object, the technical solution provided by the present invention is as follows:

[0007] In a first aspect, the present invention provides a method for dynamically optimizing the power management of a distributed battery pack of a low-altitude aircraft, which is applied to a low-altitude aircraft having multiple parallel battery packs, each battery pack being connected to one or more motors, and comprises the following steps:

[0008] Obtaining the operating parameters of each single cell in the battery pack under the operating conditions of the low-altitude aircraft;

[0009] Calculating the state of charge of the battery pack using the operating parameters, and adjusting the operating state of the low-altitude aircraft according to the support of the state of charge for the operating conditions in order to optimize power consumption; the operating state includes the operating state of the motor;

[0010] For the adjusted low-altitude aircraft, it is determined whether the battery pack has reached a balanced state according to the power state of the battery pack. If not, an active balancing strategy is used to perform battery balancing on the battery pack to optimize the battery pack state.

[0011] Further, the operating conditions include take-off conditions;

[0012] Under takeoff conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions 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 that the battery pack can currently provide based on the remaining power;

[0014] Calculate the take-off power required by the low-altitude aircraft under take-off conditions based on the design parameters of the low-altitude aircraft;

[0015] Determine whether the maximum power currently provided by the battery pack is greater than the take-off power. If so, allow the take-off operation and determine the power allocation ratio of the associated motor according to the remaining power ratio of the battery pack; if not, restrict the take-off operation.

[0016] Furthermore, the operating conditions also include cruising conditions;

[0017] Under the cruise condition, the battery pack state of charge is calculated using the operating parameters, and the low-altitude aircraft operation state is adjusted according to the support of the power state for the operating condition to optimize power consumption, including:

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

[0019] Calculate the remaining capacity of the battery pack using the operating parameters of the battery;

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

[0021] Whether the safety requirements are met is determined based on the remaining flight time. If not, the flight parameters of the low-altitude aircraft are adjusted and a new stable power is calculated 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] Under landing conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions to optimize power consumption, including:

[0024] Calculate the remaining capacity of the battery pack using the operating parameters of the battery;

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

[0026] Determine whether the landing requirements are met based on the remaining 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 of the battery pack; the state of charge and the state of voltage are determined according to the corrected current integral value and voltage integral value, respectively, as follows:

[0028]

[0029]

[0030] In the formula, For the moment of electricity, is the initial charge, From the initial time to the current time The number of time steps divided, is the error coefficient, For the time step The current value measured when is the time step; For the moment The corrected voltage, For the moment The voltage, is the temperature compensation coefficient, For the moment The discharge current, is the internal resistance of the battery.

[0031] Further, judging whether the battery pack has reached a balanced state according to the power state of the battery pack includes:

[0032] Determine whether the difference in charge state and voltage between any two battery groups is less than a set threshold. If so, it is determined that the balance state has been reached. If not, it is determined that the two battery groups are not balanced and need to be balanced according to the active balancing strategy.

[0033] Furthermore, in the active balancing strategy, performing balancing processing according to the active balancing strategy includes:

[0034] Select the corresponding motor to run according to the remaining power of the battery pack from large to small to reduce the power of the large-capacity battery pack;

[0035] Or convert energy between battery packs to reduce the power difference between battery packs.

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

[0037] The battery management system is provided with multiple parallel battery packs, and the flight control system is provided with several motors; 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 cell in the battery pack of the low-altitude aircraft under the operating conditions; it is also used to calculate the power state of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft through the flight control system according to the support of the power state for the operating conditions, so as to optimize power consumption; the operating state includes the operating state of the motor; it is also used to determine whether the battery pack has reached a balanced state according to the power state of the battery pack for the adjusted low-altitude aircraft, and if not, use an active balancing strategy to perform battery balancing on the battery pack to optimize the battery pack state.

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

[0040]

[0041]

[0042] In the formula, For the moment of electricity, is the initial charge, From the initial time to the current time The number of time steps divided, is the error coefficient, For the time step The current value measured when is the time step; For the moment The corrected voltage, For the moment The voltage, is the temperature compensation coefficient, For the moment The discharge current, is the internal resistance of the battery.

[0043] Further, judging whether the battery pack has reached a balanced state according to the power state of the battery pack includes:

[0044] Determine whether the difference in charge state and voltage between any two battery groups is less than a set threshold. If so, it is determined that the balance state has been reached. If not, it is determined that the two battery groups are not balanced and need to be balanced according to the active balancing strategy.

[0045] In summary, the present invention provides a method and system for dynamically optimizing the power management of distributed battery packs for low-altitude aircraft, which is applied to low-altitude aircraft with multiple parallel battery packs, each battery pack being connected to one or more motors. It includes obtaining the operating parameters of each single cell in the battery pack of the low-altitude aircraft under the operating conditions in which it is located; using the operating parameters to calculate the power state of the battery pack, and adjusting the operating state of the low-altitude aircraft according to the support of the power state for the operating conditions in which it is located, so as to optimize power consumption; the operating state includes the operating state of the motor; for the adjusted low-altitude aircraft, judging whether the battery pack has reached a balanced state according to the power state of the battery pack, if not, using an active balancing strategy to perform battery balancing on the battery pack to optimize the battery pack state. The present invention can solve the problems of poor endurance of drones, small operating range, and affected overall battery capacity and service life by adjusting the flight state and actively balancing the battery pack under different operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A flowchart of a method for dynamically optimizing the power management of distributed battery packs for low-altitude aircraft provided by an embodiment of the present invention;

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

[0049] Figure 3 A flow chart of a method for optimizing battery power in a cruising state provided by an embodiment of the present invention;

[0050] Figure 4 A block diagram of a system for dynamically optimizing the power management of distributed battery packs for low-altitude aircraft provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] See also Figure 1 This embodiment provides a method for dynamically optimizing the power management of distributed battery packs for low-altitude aircraft, which is applied to a low-altitude aircraft having multiple battery packs connected in parallel, each battery pack being connected to one or more motors, and includes the following steps:

[0053] S11: Obtaining operating parameters of each single cell in the battery pack under the operating conditions of the low-altitude aircraft.

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

[0055] S12: 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 power state for the operating conditions, so as to optimize power consumption; the operating state includes the operating state of the motor.

[0056] It should be noted that after obtaining the operating parameters of each single cell, using these parameters to calculate the power state of the battery pack is one of the core links. Accurate grasp of the power state is crucial to the reasonable control of aircraft operation, as it can reflect the current remaining power of the battery pack. Then, the operating state of the low-altitude aircraft is adjusted according to the support of the power state for the operating conditions. The purpose is to optimize power consumption and ensure that the aircraft can operate efficiently and stably under different conditions, avoiding power waste or affecting flight safety and performance due to insufficient power. The operating state of the motor is included in the operating state because the motor is the main component that consumes battery power. Adjusting the working conditions of the motor (such as power distribution, on and off, etc.) can directly affect the power consumption rate.

[0057] S13: For the adjusted low-altitude aircraft, determine whether the battery pack has reached a balanced state according to the power state of the battery pack. If not, use an active balancing strategy to perform battery balancing on the battery pack to optimize the battery pack state.

[0058] It should be noted that after adjusting the operating status of the aircraft, judging whether the battery pack has reached a balanced state based on the battery pack's power status is an important step to ensure the overall performance of the battery pack and the subsequent continuous and stable operation of the aircraft. Due to the influence of factors such as the battery's own characteristics and operating conditions, the power of each battery cell in the battery pack may be unbalanced. An unbalanced battery pack will not only affect the overall charging and discharging performance and service life of the battery, but may also cause problems such as power instability in the aircraft. If it is determined that the battery pack has not reached a balanced state, an active balancing strategy is used to balance the battery pack, which can make the power of each battery cell tend to be consistent, optimize the battery pack state, improve the overall consistency and stability of the battery pack, and ensure that the battery can continue to stably provide power to components such as motors during the subsequent operation of the aircraft.

[0059] The present embodiment provides a method for dynamic optimization management of power of distributed battery packs for low-altitude aircraft. First, the operating parameters of each single battery in the battery pack of the low-altitude aircraft under different operating conditions are accurately obtained, and the power state of the battery pack is accurately calculated based on this. The operating state of the low-altitude aircraft including the motor operating state is dynamically adjusted according to the support of the operating conditions by the power state to optimize power consumption. Subsequently, whether the battery pack is balanced is determined based on the power state of the adjusted battery pack. If unbalanced, an active balancing strategy is implemented to process the battery pack. Through this 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 dynamic optimization of power in the prior art are collaboratively solved, thereby achieving efficient dynamic optimization management of the power of low-altitude aircraft battery packs.

[0060] This embodiment avoids unnecessary power waste by optimizing the flight state based on the battery power state under different working conditions, so that the battery power can be used more reasonably. The active balancing strategy is used to balance the battery pack, which can promptly correct the imbalance of power among the individual cells in the battery pack, avoid damage to the overall capacity of the battery due to imbalance problems such as excessive charging and discharging of some batteries, and ensure the health of the battery during use. At the same time, the management method starts from obtaining the operating parameters of the individual cells, accurately calculates the power state, and then dynamically adjusts the flight state and performs battery balancing, forming a complete and sophisticated management process, overcoming the problem of inaccurate and inefficient battery management in the prior art, meeting the increasing demand for efficiency and accuracy of battery management in the actual use of low-altitude aircraft, ensuring the stability and reliability of aircraft flight, and improving the overall performance and use value of low-altitude aircraft.

[0061] In one embodiment, the state of charge of the battery pack includes the state of charge and the state of voltage of the battery pack; the state of charge and the state of voltage are determined according to the corrected current integral value and voltage integral value, respectively. The current integral value and the voltage integral value are calculated 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 integration algorithm

[0063] 1) Current measurement

[0064] First, the charge and discharge current of the battery pack is measured in real time by a high-precision current sensor. Assume that the measured current value is in ampere (A), where Indicates time.

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

[0066] 2) Points calculation

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

[0068] In each time step, the integral of the current over time is accumulated. is the battery capacity (unit: ampere-hour, Ah), the initial capacity is , then the integral formula is:

[0069]

[0070] in, From the initial time to the current time The number of time steps to divide into.

[0071] 3) Error correction

[0072] Since the current sensor has a certain zero drift and measurement error, error correction is required. The battery can be calibrated regularly. For example, when the battery is in a static state and the initial charge is known, the current integral value over a period of time is measured and compared with the actual charge that should remain unchanged to determine the error coefficient. The corrected current integration formula becomes:

[0073]

[0074] In the formula, is the error coefficient, For the time step The current value measured when

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

[0076] 1) Voltage measurement

[0077] Use high-precision voltage sensors to measure the terminal voltage of battery cells , the accuracy can reach ±0.01V.

[0078] 2) Temperature compensation

[0079] The voltage of the battery is closely related to the temperature. Assume that the temperature of the battery is According to the temperature characteristic curve of the battery, the influence coefficient of temperature on voltage is obtained The compensated voltage is for:

[0080]

[0081] For example, for lithium-ion batteries, when the temperature rises, the open circuit voltage of the battery will decrease. Temperature compensation can more accurately reflect the true state of the battery.

[0082] 3) Load compensation

[0083] When the battery is in a discharged state, due to the internal resistance of the battery The existence of will produce a voltage drop. Assume the discharge current is , the voltage drop caused by the load is The voltage formula after compensation becomes:

[0084]

[0085] Similarly, during the charging process, the voltage change caused by the charging current also needs to be considered and compensated accordingly.

[0086] In a further embodiment, judging whether the battery pack has reached a balanced state according to the power state of the battery pack includes:

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

[0088] The following is an introduction to the determination of the difference in charge state and the difference in voltage.

[0089] (1) SOC difference judgment

[0090] Calculate the SOC of each battery cell in the battery pack. The SOC of a battery cell is When the SOC difference between any two battery cells Greater than the set threshold (For example ), the equilibrium condition is triggered. , indicating that the SOC imbalance between battery cells exceeds the acceptable range and requires balancing operation.

[0091] (2) In addition to SOC differences, the balancing condition can also be determined based on the voltage differences of the battery cells. The voltage of a battery cell is , when the voltage difference between any two battery cells Greater than the set voltage threshold (For example ), the equilibrium condition is also triggered. , indicating that the voltage between battery cells is unbalanced, which may affect the overall performance and life of the battery pack and requires equalization adjustment.

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

[0093] When performing active equalization, first use a certain sampling frequency (For example ) while collecting the battery pack current , the voltage of each battery cell and temperature And other data.

[0094] Then the battery SOC is calculated according to the high-precision current integration algorithm, and the battery cell voltage is compensated according to the high-precision voltage compensation algorithm. Then it is determined whether the balancing condition is met.

[0095] If the SOC or voltage imbalance conditions are met, the balance control stage is entered; if not, the battery status is continuously monitored, and the battery charge and discharge process is controlled according to the battery SOC and other status information. For example, when the SOC is close to 100%, the charging current is reduced to prevent overcharging; when the SOC is low, the discharge current is reasonably allocated according to the load demand to extend the battery life.

[0096] When the balancing condition is triggered, the battery management system operates according to the balancing strategy adopted. If it is an active balancing strategy, the energy of the battery cell with higher power is transferred to the battery cell with lower power through the bidirectional DC-DC converter. Assume that the transferred power is , the transfer time is , the amount of electricity transferred is By properly controlling the transfer power and time, the SOC or voltage difference between battery cells can be gradually reduced.

[0097] In the case of a passive balancing strategy, resistors are connected in parallel to the battery cells with higher charges to cause them to discharge additionally until the difference between the battery cells is reduced to within a threshold range.

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

[0099] See also Figure 2 , Figure 2 The diagram shows a battery management system for optimizing battery pack power. The flight control system is located at the top of the diagram. The flight control system is connected to four motors (Motor, marked as M). The motor is marked as M, and each motor is connected to a battery pack. There are four battery packs, marked as 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, one below each battery pack. Each matrix switch is connected to a bidirectional DC / DC converter. There are four bidirectional DC / DC converters, one below each matrix switch. These converters are connected to the DC bus. The battery management system is located on the left side of the diagram. The battery management system is connected to four matrix switches. The following is combined with Figure 2 The active balancing strategy of the above embodiment is introduced.

[0100] like Figure 2 As shown, when the power of battery pack 1 and battery pack 4 is the largest, the motors corresponding to the flight control battery pack 1 and battery pack 4 can be used as the main power source to provide the main energy source, so that the battery power of battery packs 1, 2, 3, 4, etc. is close. At the same time, when the battery management system can also start the active balancing mode, after the matrix switch is turned on, the battery of battery pack 1 passes through the bidirectional DC / DC converter, so that the power of battery pack 1 flows to battery pack 2, and so on, so that the battery power of battery packs 1, 2, 3, 4, etc. 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 obtain stable power supply. The bidirectional DC / DC converter is used to convert power between the battery pack and the DC bus, and the matrix switch is used to select and control the connection status of the battery pack.

[0101] In the above battery pack power optimization process, the energy supply ratio of each battery pack is dynamically adjusted according to the real-time needs of the flight mission through an adaptive battery energy allocation strategy. For example, when the aircraft performs high-intensity maneuvers, energy is preferentially allocated to the battery packs corresponding to the motors that play a key role in maneuverability to ensure precise control of the flight attitude; and in the stable cruising stage, energy is evenly distributed or intelligently allocated according to the differences in battery pack power to achieve efficient utilization and power balance of the overall battery system.

[0102] Prioritizing the use of battery packs with relatively sufficient power to avoid the situation where some battery packs are over-discharged while other battery packs still have a lot of power remaining will help to make the power of each battery pack close to the same level as a whole. On this basis, in conjunction with the active balancing mode of the battery management system, a bidirectional DC / DC converter is used to realize the flow of power between different battery packs. For example, the power of battery pack 1 flows to battery pack 2, and so on. This 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, extending the overall battery life and the service life of the battery pack, because it avoids the problem of rapid battery performance degradation caused by overcharging or over-discharging of individual battery packs.

[0103] The battery management system and the flight control system work together to play a core control role, managing the charging and discharging process of the battery pack. Combined with the matrix switch's selection and control of the battery pack connection status and the bidirectional DC / DC converter's power conversion function between the battery pack and the DC bus, the motor can obtain stable power supply regardless of different flight conditions (such as take-off, cruising, landing, etc., when the power demand is different). For example, during flight, the main power source is flexibly switched according to the power status of each battery pack, and the stable output of power at the DC bus is guaranteed through power conversion and power balancing adjustment, avoiding fluctuations in motor power output due to problems such as unbalanced battery pack power or poor power conversion, thereby improving the safety and reliability of aircraft flight.

[0104] According to the different working modes of the aircraft (such as take-off, climb, cruise, and landing) and the real-time status of energy (such as battery power and remaining fuel), it automatically and smoothly switches between energy sources such as batteries and fuel generators, and optimizes the coordinated work of the two. For example, during the take-off and climb phases, batteries and fuel generators are used to provide strong power to quickly increase the altitude of the aircraft; during the cruise phase, according to the remaining battery power and fuel consumption, the output power of the two is reasonably allocated to achieve the best energy utilization efficiency and cruising range; during the landing phase, the battery is mainly used to provide stable power to ensure the safety and accuracy of the landing process.

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

[0106] Under takeoff conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions to optimize power consumption, including:

[0107] S21: Calculate the remaining power 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 power.

[0108] It should be noted that when taking off, the aircraft's flight control system first obtains the current status information of the battery pack from the battery management system, including the remaining battery power ( ), the voltage of each battery cell and temperature Etc. Calculated by high-precision current integration algorithm , for example, set the current The maximum power that the battery pack can provide can then be determined based on the remaining charge.

[0109] S22: Calculate the take-off power required by the low-altitude aircraft under take-off conditions based on the design parameters of the low-altitude aircraft.

[0110] It should be noted that according to the take-off weight of the aircraft , acceleration required for takeoff and aerodynamic parameters, etc., to calculate the power required for takeoff Assume that the relationship between the thrust and power of the aircraft is (in , is the acceleration due to gravity, is the takeoff speed).

[0111] S23: Determine whether the maximum power currently provided by the battery pack is greater than the take-off power. If so, allow the take-off operation and determine the power distribution ratio of the associated motors according to the remaining power ratio of the battery pack; if not, restrict the take-off operation.

[0112] It should be noted that the aircraft's battery management system evaluates whether it can provide enough power to meet takeoff requirements based on the current battery status. ( The maximum power that the battery pack can provide. , voltage and internal resistance, etc. , is the efficiency of the battery pack, is the total voltage of the battery pack, is the maximum allowable discharge current), the takeoff operation is allowed to continue; otherwise, the operating status of the low-altitude aircraft is adjusted, such as the flight control system issuing a warning and restricting takeoff.

[0113] Under takeoff conditions, battery balancing and power distribution adjustment are required. That is, during takeoff, the battery status is continuously monitored. If there is a difference in SOC between battery cells in the battery pack, or voltage difference (As mentioned above, the balancing condition threshold), the battery management system starts the balancing operation.

[0114] For active balancing, the energy distribution between battery cells is adjusted through a bidirectional DC-DC converter to ensure the overall stability of the battery pack. At the same time, according to the status of the battery cells, the flight control system can adjust the power distribution of the motor. For example, if the voltage of a battery cell is low, the power distribution ratio of the motor associated with it is appropriately reduced. , assuming the total motor power is , No. The power of the motor ,in Dynamic adjustments are made based on the voltage, SOC and other conditions of the battery cells to ensure the safety and stability of the overall flight.

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

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

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

[0118] It should be noted that after entering the cruise phase, according to the current flight altitude , Flight speed , air resistance Calculate the stable power required for cruising using other parameters (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 battery power can be accurately calculated by combining the high-precision current integration algorithm and the voltage compensation algorithm. .

[0121] S33: Calculate the remaining battery life based on the remaining power and the stable power.

[0122] It should be noted that the remaining endurance time is estimated based on the remaining battery power and cruising power. (in is the remaining power calculated based on SOC, = , is the rated capacity of the battery pack).

[0123] S34: 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.

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

[0125] Under cruising conditions, battery status maintenance and balancing strategy optimization are required. During cruising, the voltage and temperature changes of battery cells are continuously monitored. Since the load is relatively stable during cruising, more attention is paid to the long-term health maintenance of the battery. Above the safe temperature limit , the flight control system works with the battery management system to adjust the aircraft's 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 requirements, the frequency and energy transfer of active balancing can be appropriately increased to further reduce the SOC and voltage differences between battery cells and improve the overall consistency and life of the battery pack. For example, increase the power transfer of active balancing , so that the SOC difference of battery cells gradually decreases during cruising.

[0127] .

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

[0129] Under landing conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions to optimize 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 command, it first obtains the remaining battery power from the battery management system. and the voltage status of the battery pack.

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

[0133] It should be noted that the remaining power is sufficient to support various operations during landing, including the power requirements of auxiliary systems such as landing gear lowering and flap adjustment. .

[0134] S41: Determine whether the landing requirements are met based on the remaining 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.

[0135] It should be noted that if ( is the battery discharge efficiency, If the aircraft is within the estimated landing time, the normal landing procedure is allowed. Otherwise, the flight control system will take emergency measures, such as giving priority to the power supply of key systems, reducing the power consumption of non-key systems, or trying to land at a closer suitable location.

[0136] During landing, battery safety and fault handling must be considered. During landing, the battery pack status should be closely monitored. If a battery cell is over-discharged (voltage is lower than the over-discharge threshold), ) or other abnormal situations, the flight control system will take immediate measures, such as cutting off the circuits related to the abnormal battery cells, 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, the battery status data during the landing process is recorded, including the change curves of SOC, voltage, temperature, etc., so as to analyze and optimize the battery management strategy later and improve the battery efficiency and flight safety of the aircraft under different working conditions.

[0137] By closely coordinating the flight control system and the battery management system under different operating conditions such as take-off, cruising and landing, the effective control and optimized operation of the aircraft can be achieved by comprehensively considering multiple factors such as the aircraft's power requirements, battery status and flight safety.

[0138] See also Figure 3 , Figure 3 The process of battery optimization management under cruising conditions is shown, including the following steps:

[0139] 1. The process starts.

[0140] 2. The system sends instructions:

[0141] The system first sends the command.

[0142] 3. Obtain the power status of each battery pack, motor power status, power direction, etc.:

[0143] The system obtains information such as the charge status of each battery pack, the power status of the motor, and the power direction.

[0144] 4. In the cruising state, whether the battery pack reaches a balanced state:

[0145] The system checks whether the battery pack has reached a balanced state in the cruise state. If it has reached a balanced state, the process jumps to the "End" node. If it has not reached a balanced state, it proceeds to the next step.

[0146] 5. The battery pack with the largest capacity charges the battery pack with the smallest capacity:

[0147] The system allows the battery pack with the largest charge to charge the battery pack with the smallest charge.

[0148] 6. The battery pack with the largest capacity mainly provides power to the motor:

[0149] The battery pack with the largest capacity is mainly responsible for providing the electrical energy required by the motor.

[0150] 7. The flight control system controls the balance of the aircraft:

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

[0152] 8. Whether the battery pack has reached a balanced state:

[0153] The system checks again whether the battery pack has reached a balanced state. If it has reached a balanced state, the process jumps to the "End" node. If it has not reached a balanced state, the process returns to step 5 to continue charging and balancing control operations.

[0154] 9. End:

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

[0156] Under normal conditions, the battery management system sends instructions to obtain the battery power status of each battery pack, and obtains the battery power status, power direction, etc. from the flight control system. When the aircraft is flying in a cruising state, if the battery pack is in an unbalanced state, the battery pack with the largest power will charge the battery pack with the smallest power; when the SOC power status difference between the battery packs is more than 5% or the SOC power status of a battery pack is less than 30%, the system will start the flight control balance mode. During the flight, by controlling the working conditions of the motor, the battery pack with the highest power will be used for power supply first. At the same time, the approach system controls the balance of the aircraft.

[0157] See also Figure 4 , the embodiment of the present invention also provides a low-altitude aircraft distributed battery pack power dynamic optimization management system, including: a flight control system and a battery management system;

[0158] The battery management system is provided with multiple parallel battery packs, and the flight control system is provided with several motors; 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 cell in the battery pack of the low-altitude aircraft under the operating conditions; it is also used to calculate the power state of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft through the flight control system according to the support of the power state for the operating conditions, so as to optimize power consumption; the operating state includes the operating state of the motor; it is also used to determine whether the battery pack has reached a balanced state according to the power state of the battery pack for the adjusted low-altitude aircraft, and if not, use an active balancing strategy to perform battery balancing on the battery pack to optimize the battery pack state.

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

[0161]

[0162]

[0163] In the formula, For the moment of electricity, is the initial charge, From the initial time to the current time The number of time steps divided, is the error coefficient, For the time step The current value measured when is the time step; For the moment The corrected voltage, For the moment The voltage, is the temperature compensation coefficient, For the moment The discharge current, is the internal resistance of the battery.

[0164] Further, judging whether the battery pack has reached a balanced state according to the power state of the battery pack includes:

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

[0166] Further, the operating conditions include take-off conditions;

[0167] Under takeoff conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions to optimize power consumption, including:

[0168] Calculate the remaining power of the battery pack using the operating parameters of the battery, and determine the maximum power that the battery pack can currently provide based on the remaining power;

[0169] Calculate the take-off power required by the low-altitude aircraft under take-off conditions based on the design parameters of the low-altitude aircraft;

[0170] Determine whether the maximum power currently provided by the battery pack is greater than the take-off power. If so, allow the take-off operation and determine the power allocation ratio of the associated motor according to the remaining power ratio of the battery pack; if not, restrict the take-off operation.

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

[0172] Under the cruise condition, the battery pack state of charge is calculated using the operating parameters, and the low-altitude aircraft operation state is adjusted according to the support of the power state for the operating condition to optimize power consumption, including:

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

[0174] Calculate the remaining capacity of the battery pack using the operating parameters of the battery;

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

[0176] Whether the safety requirements are met is determined based on the remaining flight time. If not, the flight parameters of the low-altitude aircraft are adjusted and a new stable power is calculated until the remaining flight time of the adjusted low-altitude aircraft meets the safety requirements.

[0177] Furthermore, the operating conditions also include landing conditions;

[0178] Under landing conditions, the battery pack state of charge is calculated using operating parameters, and the low-altitude aircraft operation is adjusted based on the support of the state of charge for the operating conditions to optimize power consumption, including:

[0179] Calculate the remaining capacity of the battery pack using the operating parameters of the battery;

[0180] Calculate the auxiliary power required for low-altitude aircraft during landing;

[0181] Determine whether the landing requirements are met based on the remaining 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.

[0182] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for dynamic optimization management of distributed battery pack power of low-altitude aircraft, characterized in that: The invention is applied to a low-altitude aircraft having multiple battery packs connected in parallel, each battery pack being connected to one or more motors, and comprises the following steps: Obtaining operating parameters of each single battery in the battery pack under the operating conditions of the low-altitude aircraft; Calculating the power state of the battery pack using the operating parameters, and adjusting the operating state of the low-altitude aircraft according to the support of the power state for the operating condition, so as to optimize power consumption; the operating state includes the operating state of the motor; For the adjusted low-altitude aircraft, it is determined whether the battery pack has reached a balanced state according to the power state of the battery pack. If not, an active balancing strategy is used to perform battery balancing on the battery pack to optimize the battery pack state.

2. The method for dynamic optimization management of distributed battery pack power of low-altitude aircraft according to claim 1 is characterized in that: The operating conditions include take-off conditions; Under the take-off condition, the power state 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 power state for the operating condition to optimize power consumption, including: Calculating the remaining power of the battery pack using the operating parameters of the battery, and determining the maximum power that the battery pack can currently provide according to the remaining power; Calculating 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; Determine whether the maximum power that the battery pack can currently provide is greater than the take-off power. If so, allow the take-off operation and determine the power allocation ratio of the associated motor according to the remaining power ratio of the battery pack; if not, restrict the take-off operation.

3. The method for dynamic optimization management of distributed battery pack power of low-altitude aircraft according to claim 1 is characterized in that: The operating conditions also include cruising conditions; Under the cruising condition, the power state 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 power state for the operating condition to optimize power consumption, including: Calculating the stable power required for cruising of the low-altitude aircraft according to the flight parameters of the low-altitude aircraft; Calculating the remaining power of the battery pack using the operating parameters of the battery; Calculating the remaining battery life according to the remaining power and the stable power; 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 the new stable power until the remaining flight time of the low-altitude aircraft after adjustment meets the safety requirements.

4. The method for dynamic optimization management of distributed battery pack power of low-altitude aircraft according to claim 1 is characterized in that: The operating conditions also include landing conditions; Under the landing condition, the power state 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 power state for the operating condition to optimize power consumption, including: Calculating the remaining power of the battery pack using the operating parameters of the battery; Calculating the auxiliary power required by the low-altitude aircraft during landing; It is determined whether the landing requirements are met according to the remaining power, the auxiliary power and the landing time. If not, the flight parameters of the low-altitude aircraft are adjusted to reduce power consumption or change the landing location.

5. The method for dynamic optimization management of power of distributed battery packs of low-altitude aircraft according to any one of claims 1 to 4, characterized in that: The state of charge of the battery pack includes the state of charge and the state of voltage of the battery pack; the state of charge and the state of voltage are determined according to the corrected current integral value and voltage integral value, respectively, as follows: In the formula, For the moment of electricity, is the initial charge, From the initial time to the current time The number of time steps divided, is the error coefficient, For the time step The current value measured when is the time step; For the moment The corrected voltage, For the moment The voltage, is the temperature compensation coefficient, For the moment The discharge current, is the internal resistance of the battery.

6. The method for dynamic optimization management of power of distributed battery packs of low-altitude aircraft according to any one of claim 5, characterized in that: Determining whether the battery pack has reached a balanced state according to the power state of the battery pack includes: It is determined whether the difference in charge state and voltage between any two of the battery packs is less than a set threshold. If so, it is determined that a balanced state is reached. If not, it is determined that the two battery packs are not balanced and need to be balanced according to the active balancing strategy.

7. The method for dynamic optimization management of power of distributed battery packs of low-altitude aircraft according to any one of claim 1, characterized in that: In the active balancing strategy, performing balancing processing according to the active balancing strategy includes: Selecting the corresponding motor to operate according to the remaining power of the battery pack from large to small, so as to reduce the power of the large-capacity battery pack; Or energy conversion is performed between the battery groups to reduce the power difference between the battery groups.

8. A low-altitude aircraft distributed battery pack power dynamic optimization management system, characterized in that: include: Flight control system and battery management system; The battery management system is provided with a plurality of parallel battery packs, and the flight control system is provided with a plurality of motors; Each battery pack is connected to one or more motors; The battery management system is used to obtain the operating parameters of each single cell in the battery pack under the operating conditions of the low-altitude aircraft; it is also used to calculate the power state of the battery pack using the operating parameters, and adjust the operating state of the low-altitude aircraft through the flight control system according to the support of the power state for the operating conditions, so as to optimize power consumption; the operating state includes the operating state of the motor; it is also used to determine whether the battery pack has reached a balanced state according to the power state of the battery pack for the adjusted low-altitude aircraft, and if not, use an active balancing strategy to perform battery balancing on the battery pack to optimize the battery pack state.

9. The low-altitude aircraft distributed battery group power dynamic optimization management system according to claim 8 is characterized in that: The state of charge of the battery pack includes the state of charge and the state of voltage of the battery pack; the state of charge and the state of voltage are determined according to the corrected current integral value and voltage integral value, respectively, as follows: In the formula, For the moment of electricity, is the initial charge, From the initial time to the current time The number of time steps divided, is the error coefficient, For the time step The current value measured when is the time step; For the moment The corrected voltage, For the moment The voltage, is the temperature compensation coefficient, For the moment The discharge current, is the internal resistance of the battery.

10. The low-altitude aircraft distributed battery group power dynamic optimization management system according to claim 9 is characterized in that: Determining whether the battery pack has reached a balanced state according to the power state of the battery pack includes: It is determined whether the difference in charge state and voltage between any two of the battery packs is less than a set threshold. If so, it is determined that a balanced state is reached. If not, it is determined that the two battery packs are not balanced and need to be balanced according to the active balancing strategy.

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