A Battery Pack Balancing Control Method for Long-Endurance Drones

Abstract

This invention proposes a battery pack balancing control method for long-endurance drones, which can dynamically adjust the actual output power of each individual battery and the battery pack to achieve balanced discharge. The invention employs an autonomous balancing control unit and a constant output control unit. The autonomous balancing control unit dynamically adjusts the actual output power of each battery pack to achieve balanced discharge. This avoids the problem of excessive discharge of individual battery packs due to uneven discharge among multiple battery packs, which can lead to a rapid decrease in the overall battery capacity and effectively extend the drone's flight time. The constant output control unit ensures a constant power output from the drone's power system to meet the stable power supply requirements of the long-endurance drone's onboard electronics and power equipment.

Description

Technical Field

[0001] This invention relates to the field of battery pack equalization control technology, and specifically to a battery pack equalization control method for long-endurance drones. Background Technology

[0002] In recent years, with the continuous development of computer technology, communication technology, microelectromechanical systems (MEMS) technology, and embedded technology, purely electric drones have gradually come into view and are widely used in fields such as aerial photography, logistics transportation, geographic surveying, biological monitoring, environmental protection, disaster relief, precision agriculture, security maintenance, and meteorological monitoring. However, due to limitations in battery storage technology, the flight time of drones is generally short. The only way to extend the flight time is to increase the number of battery packs, sacrificing payload weight, without affecting the drone's center of gravity. In practical use, several battery packs are usually cross-combined in series or parallel to provide power to the drone system. While this method is simple to operate, it is highly likely to reduce the lifespan of the battery packs or even damage the drone's electronic systems.

[0003] Existing equalization control methods for individual cells / battery packs typically involve connecting switching devices and their series-connected energy-consuming resistors in parallel with each individual cell / pack. A voltage acquisition circuit collects the output voltage of all individual cells / packs and calculates the voltage difference between each individual cell / pack and the cell / pack with the lowest voltage value. When this voltage difference exceeds a predetermined voltage threshold, a control module opens or closes the switching devices connected in parallel to each individual cell / pack, creating a discharge loop for the cell / pack with the higher voltage value. The energy-consuming resistor then discharges the higher-voltage cell / pack until the voltage difference between all individual cells / packs falls below the predetermined voltage threshold, thus completing the equalization control task. While this equalization control method is simple in structure and easy to operate, it also has certain technical drawbacks. This method can only control the voltage difference between different individual cells / cells within a specific voltage threshold range. However, under high-power discharge conditions, it cannot guarantee that all individual cells / cells have the same discharge rate, nor can it guarantee that individual cells / cells will not over-discharge. Furthermore, the energy-dissipating resistors commonly used in the equalization control process are a purely energy-dissipating method. Achieving equalization control comes at the cost of shortening the effective operating time of individual cells / cells, resulting in some energy waste. Summary of the Invention

[0004] In view of this, the present invention proposes a battery pack equalization control method for long-endurance drones, which can dynamically adjust the actual output power of each individual battery and the battery pack to achieve balanced discharge.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] The present invention discloses a battery pack balancing control method for long-endurance drones. The system includes a power input module, a power transmission module, a power output module, and a power detection and control module; control is achieved through an autonomous balancing control unit and a constant output control unit.

[0007] The autonomous balancing control unit collects the output voltage information of all battery packs in real time, obtaining the output voltage information sequence {V1,...,V1,...} of the battery packs. i ,...,V N}, where V i This represents the output voltage information of the i-th battery pack, where i ∈ {1, 2, ..., N}, and N is the total number of battery packs, where N ≥ 2; the minimum output voltage V in the voltage information sequence is... MIN The target voltage for equalization is set as lim; the equalization target of the autonomous equalization control unit is lim. t→∞ ||V i -V MIN ||=0, where t is the equilibrium time.

[0008] The equilibrium objective is achieved under the following equilibrium control law:

[0009]

[0010] Among them, U i The control signal quantity applied to the i-th battery pack; the first term α∑(V) in the equalization control law i -V j This is used to achieve near-uniform output voltage across all battery packs; the second term β(V) in the equalization control law... i -V MIN This is used to make the output voltage of the i-th battery pack tend towards the equilibrium target voltage V. MIN Furthermore, the first and second terms of the equalization control law together characterize the equalization control signal strength applied to the i-th battery pack; the third term of the equalization control law The discharge control signal strength applied to all battery packs is dynamically adjusted based on the load output; α and β are configurable control parameters.

[0011] The output voltage of each battery pack is isolated and transmitted to the power transmission module under the action of the equalization control law. The constant output control unit dynamically adjusts the control signal applied to the power transmission module to achieve a constant output target V. O ≡V obj V O The actual output voltage information of the constant output control unit is the voltage signal strength required by the onboard electronics and power equipment of the long-endurance UAV.

[0012] Wherein, the constant output target V O ≡V obj This is achieved under the following constant output control law:

[0013]

[0014] Among them, U O η and η are the control signal quantities applied to the power transmission module. As configurable control parameters, under the action of the constant output control law, the constant output control unit outputs voltage information V. O Constant at V obj .

[0015] Among them, the control signal quantity U of the constant output control law O The discharge control signal strength of the third term in the equalization control law There is a function mapping relationship.

[0016] Beneficial effects:

[0017] The present invention provides a battery pack equalization control method for long-endurance drones, which can dynamically adjust the actual output power of each battery pack to achieve balanced discharge, avoid the problem of excessive discharge of individual battery packs caused by uneven discharge of multiple battery packs, and effectively extend the flight time of the drone. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the system used in the battery pack equalization control method for long-endurance drones of the present invention.

[0019] Figure 2 This is a schematic diagram of the power input module of the system used in the battery pack equalization control method for long-endurance drones of the present invention.

[0020] Figure 3 This is a schematic diagram of the power transmission module of the system used in the battery pack equalization control method for long-endurance drones of the present invention.

[0021] Figure 4This is a schematic diagram of the power output module of the system used in the battery pack equalization control method for long-endurance drones of the present invention.

[0022] Figure 5 This is a schematic diagram of the power detection and control module of the system used in the battery pack equalization control method for long-endurance drones of the present invention. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] The system used in the battery pack balancing control method for long-endurance drones of the present invention is as follows: Figure 1 As shown, it includes a power input module 100, a power transmission module 200, a power output module 300, and a power detection and control module 400.

[0025] Figure 2 This is a schematic diagram of the power input module of a system used in a battery pack equalization control method for a long-endurance drone according to the present invention. The power input module 100 includes at least two battery packs 101 and 102, and can be extended to a battery pack number 10N, where N represents the number of battery packs and N≥2.

[0026] Figure 3 This is a schematic diagram of the power transmission module of a system used in a battery pack equalization control method for a long-endurance drone according to the present invention; the power transmission module 200 includes a primary transmission unit 210 and a secondary transmission unit 211.

[0027] Figure 4 This is a schematic diagram of the power output module of the system used in the battery pack balancing control method for long-endurance drones of the present invention; the power output module 300 is the actual output power port of the power management system.

[0028] Figure 5 This is a schematic diagram of the power detection and control module of a system used in a battery pack balancing control method for long-endurance drones according to the present invention. The power detection and control module 400 includes an information acquisition array 401, a power management controller 402, and a pulse width modulation circuit array 403.

[0029] Furthermore, the power input module 100 may contain battery packs of the same or different models. Each battery pack is independently installed in the power input module 100, and there is no electrical connection of any kind between the battery packs, such as series, parallel or other arbitrary combination of connection methods.

[0030] Furthermore, the primary transmitter unit 210 mainly includes a primary high-frequency inverter circuit array 201, a primary high-frequency transformer array 202, a primary rectifier circuit array 203, and a primary filter circuit 204. The primary high-frequency inverter circuit array 201 can output a control signal U to the equalization control unit. i Driven by the power supply, the DC power supplied by each battery pack is inverted into high-frequency AC power and then isolated and output through a first-stage high-frequency transformer array 202. This is combined with the control signal U of the equalization control law described in this embodiment. i The pulse width modulation signals PWM1 to PWMN are used to represent the voltage, where i ∈ {1,2,...,N}. The first-stage rectifier circuit array 203 can rectify the high-frequency AC power output from the first-stage high-frequency transformer array 202 into DC power, which is then serially connected, superimposed, and output to the second-stage transmitter unit 211 via the first-stage filter circuit 204.

[0031] Furthermore, the secondary transmitter unit 211 mainly includes a secondary high-frequency inverter circuit 205, a secondary high-frequency transformer 206, a secondary rectifier circuit 207, and a secondary filter circuit 208. The secondary high-frequency inverter circuit 205 outputs a control signal U at the constant output control circuit. O Driven by the current, the DC power output from the first-stage filter circuit 204 is inverted into high-frequency AC power with a specific amplitude and then isolated and output via the second-stage high-frequency transformer 206. This is combined with the control signal U of the constant output control law described in this embodiment. O This is represented by a pulse width modulation signal (PWMO). The secondary rectifier circuit 207 rectifies the high-frequency AC power output from the secondary high-frequency transformer 206 into DC power, which is then output to the power output module 300 via the secondary filter circuit 208.

[0032] Furthermore, the information acquisition array 401 can acquire in real time the voltage, current, temperature, and humidity information S1 to SN of each battery pack in the power input module 100, as well as the output voltage and current information SO of the power output module 300, through non-contact methods such as photoelectric isolation or electromagnetic induction, and transmit all the acquired information to the power management controller 402. The power management controller 402 can dynamically adjust the control signals PWM1 to PWMN of the equalization control law applied to the first-stage high-frequency inverter circuit array 201 according to the measured voltage and / or current data of each battery pack in the power input module 100, controlling the high-capacity battery packs to release more power while reducing the discharge of the low-capacity battery packs. Under the premise of ensuring that the actual output voltage and / or current of the power output module 300 remains constant, the power consumption rate of each battery pack is made closer to uniform, avoiding damage to the low-capacity battery packs due to over-discharge.

[0033] Furthermore, the power management controller 402 can dynamically adjust the control signal PWMO applied to the constant output control law of the secondary high-frequency inverter circuit 205 according to the measured output voltage and / or current data 301 of the power output module 300, so that the power output module 300 achieves a constant output target V. O ≡V obj This is to meet the stable power supply requirements of the onboard electronics and power equipment of long-endurance drones.

[0034] Furthermore, the pulse width modulation circuit array 403 can condition the control signal quantities PWM1~PWMN and PWM0 output by the equalization control law and the constant output control law to drive signals that can be used to drive the first-stage high-frequency inverter circuit array 201 and the second-stage high-frequency inverter circuit 205, and the connection between the drive signal and the first-stage high-frequency inverter circuit array 201 and the second-stage high-frequency inverter circuit 205 adopts a non-contact method such as opto-isolation or electromagnetic induction.

[0035] Based on the system of this invention, this invention provides a battery pack equalization control method for long-endurance drones. This method can dynamically adjust the actual output power of each individual battery and the battery pack to achieve balanced discharge, avoiding the problem of excessive discharge of individual battery packs due to uneven discharge of multiple battery packs, which causes the overall power of the drone to drop too quickly. This effectively extends the flight time of the drone. This invention uses an autonomous equalization control unit and a constant output control unit for control. Specifically, the autonomous equalization control unit collects the output voltage information of all battery packs in real time, obtaining the battery pack output voltage information sequence {V1,...,V...}. i ,...,V N}, where V i Let V represent the output voltage information of the i-th battery pack, where i ∈ {1, 2, ..., N}, and N is the total number of battery packs, where N ≥ 2. The minimum output voltage V in the voltage information sequence is then used. MIN The target voltage for equalization is set as lim. t→∞ ||V i -V MIN ||=0, where t is the equilibrium time.

[0036] Furthermore, the equilibrium objective is achieved under the following equilibrium control law:

[0037]

[0038] Among them, U i This is the control signal quantity applied to the i-th battery pack. The first term α∑(V) in the equalization control law... i -V jThis is used to achieve near-uniform output voltage across all battery packs; the second term β(V) in the equalization control law... i -V MIN This is used to make the output voltage of the i-th battery pack tend towards the equilibrium target voltage V. MIN Furthermore, the first and second terms of the equalization control law together characterize the equalization control signal strength applied to the i-th battery pack; the third term of the equalization control law The discharge control signal strength of all battery packs can be dynamically adjusted according to the load output. α and β are configurable control parameters. Under the action of the aforementioned equalization control law, each battery pack can dynamically adjust its actual output power to achieve balanced discharge. This avoids the problem of excessive discharge of individual battery packs due to uneven discharge among multiple battery packs, which can lead to a rapid drop in the overall battery capacity and effectively extend the flight time of the drone.

[0039] Furthermore, the output voltage of each battery pack is isolated and transmitted to the power transmission module under the action of the equalization control law. The constant output control unit dynamically adjusts the control signal applied to the power transmission module to achieve a constant output target V. O ≡V obj V O V represents the actual output voltage information of the constant output control unit. obj The voltage signal strength required for the onboard electronics and power equipment of long-endurance drones.

[0040] Furthermore, the constant output target V O ≡V obj This is achieved under the following constant output control law:

[0041]

[0042] Among them, U O η is the control signal quantity applied to the power transmission module. These are configurable control parameters. Under the action of the constant output control law, the constant output control unit can keep its output voltage information constant at V. obj This is to meet the stable power supply requirements of the onboard electronics and power equipment of long-endurance drones.

[0043] Furthermore, the control signal U of the constant output control law O The discharge control signal strength of the third term in the equalization control law There exists a certain linear or nonlinear function mapping relationship. That is, the equilibrium control law can be based on the control signal U of the constant output control law. O Dynamically adjust the intensity of the discharge control signal Together, they constitute a battery pack equalization control method for long-endurance drones according to the present invention.

[0044] It should be noted that in this invention, relational terms such as first, second, primary, secondary, etc., are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms include, encompass, or any other variations are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed. Alternatively, it may include elements inherent to such a process, article, method, or apparatus.

[0045] The above description is merely one embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A battery pack equalization control method for long-endurance drones, characterized by, The system comprises a power input module, a power transmission module, a power output module and a power detection and control module; and is controlled by a self-balancing control unit and a constant output control unit. The autonomous equalization control unit collects output voltage information of all battery packs in real time to obtain an output voltage information sequence {V1,...,V i ,...,V N} of the battery packs, wherein V i represents output voltage information of the i-th battery pack, i∈{1,2,...,N}, N is the total number of battery packs, and N≥2; the minimum output voltage V MIN in the voltage information sequence is set as an equalization target voltage; and the equalization target of the autonomous equalization control unit is lim t→∞ ||V i -V MIN ||=0, wherein t is an equalization time. The balancing target is achieved under the action of a balancing control law as follows: wherein, U i is the control signal amount applied to the i-th battery pack; the first term α∑(V i -V j ) in the equalization control law is used to realize the output voltages of all battery packs approaching uniformity; the second term β(V i -V MIN ) in the equalization control law is used to realize the output voltage of the i-th battery pack tending to the equalization target voltage V MIN , and the first and second terms in the equalization control law jointly represent the strength of the equalization control signal amount applied to the i-th battery pack; the third term is the discharge control signal amount strength applied to all battery packs, which is dynamically adjusted according to the load output condition; and α and β are configurable control parameters.

2. The method of claim 1, wherein, The output voltage of each battery pack is isolated and delivered to the power transmission module under the action of the equalization control law. The constant output control unit dynamically adjusts the amount of control signals applied to the power transmission module to achieve the constant output target V O ≡V obj , where V O is the actual output voltage information of the constant output control unit. The voltage signal strength required by the onboard electronics and power equipment of the long-endurance unmanned aerial vehicle.

3. The method of claim 2, wherein, The constant output target V O ≡ V obj is achieved under the action of the following constant output control law: Wherein, U O is the control signal quantity applied to the power transmission module, η and is a configurable control parameter, under the action of the constant output control law, the constant output control unit keeps the voltage information V O constant at V obj .

4. The method of claim 3, wherein, The control signal amount U of the constant output control law O The discharge control signal amount intensity of the third term in the equalization control law There is a function mapping relationship.

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