CN215322099U

CN215322099U - Battery management system

Info

Publication number: CN215322099U
Application number: CN202121003064.9U
Authority: CN
Inventors: 秦威
Original assignee: Shenzhen Autel Intelligent Aviation Technology Co Ltd
Current assignee: Shenzhen Autel Intelligent Aviation Technology Co Ltd
Priority date: 2021-05-11
Filing date: 2021-05-11
Publication date: 2021-12-28
Anticipated expiration: 2031-05-11

Abstract

The embodiment of the utility model discloses a battery management system, which comprises: the system comprises a battery pack, an electric quantity metering device and a microprocessor; the electric quantity metering device is respectively connected with the battery pack and the microprocessor and is used for detecting the voltage, the current and the temperature information of the battery pack, determining the battery electric quantity of the battery pack and transmitting the battery electric quantity to the microprocessor; the microprocessor is used for generating a first control signal for battery management according to the electric quantity of the battery; the battery pack at least comprises two batteries connected in series, is also connected with the microprocessor and is used for supplying power to the electric quantity metering device and the microprocessor. According to the technical scheme of the embodiment of the utility model, the battery pack is used as a whole to calculate the battery electric quantity, so that the electric quantity calculation precision is improved, the high-precision management of the multi-battery pack is realized, the battery management flexibility is improved, and the information processing complexity of a microprocessor is reduced.

Description

Battery management system

Technical Field

The embodiment of the utility model relates to the technical field of battery management, in particular to a battery management system.

Background

Along with the gradual rise of agricultural unmanned aerial vehicles, the demand of the unmanned aerial vehicles on power is also increased day by day. The improvement of power means the increase of battery quantity in the group battery, and because the restriction of technology and product structure, the many battery management schemes to unmanned aerial vehicle are not yet many at present.

At present, aiming at the management of a battery pack formed by connecting multiple batteries in an unmanned aerial vehicle in series, the unmanned aerial vehicle microprocessor is used for independently managing each battery in the battery pack, obtaining information such as current, voltage and temperature corresponding to each battery, and further determining the electric quantity of each battery and adjusting the charging and discharging of different batteries.

However, in the existing management technology, each battery in the battery pack is not taken as a whole, the calculation amount required by independent control is large, the error is large, the complexity of multi-battery pack management is increased, and flexible and high-precision battery management is difficult to realize.

SUMMERY OF THE UTILITY MODEL

The utility model provides a battery management system, which is used for realizing high-precision management of a multi-battery series battery pack, so that the electric quantity precision of the battery pack can meet the safety requirement of an unmanned aerial vehicle, the flexibility of battery management is improved, and the management complexity is reduced.

An embodiment of the present invention provides a battery management system, including: the system comprises a battery pack, an electric quantity metering device and a microprocessor;

the electric quantity metering device is respectively connected with the battery pack and the microprocessor and is used for detecting the voltage, the current and the temperature information of the battery pack, determining the battery electric quantity of the battery pack and transmitting the battery electric quantity to the microprocessor;

the microprocessor is used for generating a first control signal for battery management according to the electric quantity of the battery;

the battery pack at least comprises two batteries connected in series, is also connected with the microprocessor and is used for supplying power to the electric quantity metering device and the microprocessor.

Further, the electricity metering device comprises: the device comprises a current and voltage sampling module, a first temperature sensor and an electric quantity metering chip;

the current and voltage sampling module is connected with a pin of the electric quantity metering chip and used for acquiring sampling voltage and sampling current of the battery pack and sending the sampling voltage and the sampling current to the electric quantity metering chip;

the output end of the first temperature sensor is connected with a pin of the electric quantity metering chip and is used for acquiring the average temperature in the battery pack and sending the average temperature to the electric quantity metering chip;

the electric quantity metering chip is connected with the current and voltage sampling module, the first temperature sensor and the microprocessor through different pins respectively, and is used for determining the electric quantity of the battery pack according to the received sampling voltage, sampling current and average temperature and transmitting the electric quantity of the battery to the microprocessor;

wherein, the electric quantity metering chip is a single battery electric quantity metering chip.

Further, the current-voltage sampling module includes:

current detection resistance and divider resistance, wherein:

the voltage dividing resistor is connected to two ends of the battery pack in parallel and used for acquiring sampling voltage, and the sampling voltage is the ratio of the output voltage of the battery pack to the number of batteries in the battery pack;

the current detection resistor is directly connected in series with the main loop and connected in series with one end of the battery pack and used for obtaining sampling current, the sampling current is current flowing through the battery pack, and the main loop is a loop formed by connecting an output anode, a battery pack cathode and an output cathode.

Further, the microprocessor is specifically configured to:

if the electric quantity of the battery is smaller than a preset first electric quantity threshold value, determining the generated pre-charging signal as a first control signal;

if the electric quantity of the battery is greater than or equal to a preset first electric quantity threshold value and smaller than a preset second electric quantity threshold value, determining the generated main loop switch closing signal as a first control signal;

if the electric quantity of the battery is greater than or equal to a preset second electric quantity threshold value and smaller than a preset third electric quantity threshold value, determining the generated pre-discharge signal as a first control signal;

and if the electric quantity of the battery is greater than or equal to a preset third electric quantity threshold value, determining the generated main loop switch disconnection signal as a first control signal.

Further, the battery management system further includes: an analog front end device;

the analog front-end device is respectively connected with the battery pack and the microprocessor and is used for detecting the voltage and the current of each battery in the battery pack and the highest temperature in the battery pack, generating a second control signal for battery management according to the voltage, the current and the highest temperature and transmitting the voltage, the current and the highest temperature to the microprocessor;

correspondingly, the microprocessor is also used for generating a third control signal for battery management according to each voltage, each current and each highest temperature.

Further, the analog front end device comprises: a second temperature sensor and an analog front-end chip;

the output end of the second temperature sensor is connected with a pin of the analog front-end chip and is used for acquiring the highest temperature in the battery pack and sending the highest temperature to the analog front-end chip;

and the analog front-end chip is connected with the second temperature sensor, the microprocessor and the positive ends of the batteries in the battery pack through different pins respectively, and is used for generating a second control signal for battery management according to the received highest temperature and the acquired voltage and current of each battery in the battery pack and transmitting each voltage, each current and the highest temperature to the microprocessor.

Further, the analog front-end chip is specifically configured to:

if all the currents are smaller than a preset first current threshold and the highest temperature is smaller than a preset first temperature threshold, determining the generated pre-charging signal as a second control signal;

if each current is greater than or equal to a preset first current threshold and less than a preset second current threshold, and the highest temperature is less than a preset first temperature threshold, determining the generated main loop switch closing signal as a second control signal;

if each current is greater than or equal to a preset second current threshold and less than a preset third current threshold, and the highest temperature is less than a preset first temperature threshold, determining the generated pre-discharge signal as a second control signal;

if any current is greater than or equal to a preset third current threshold value, or the highest temperature is greater than or equal to a preset first temperature threshold value, determining the generated main loop switch disconnection signal as a second control signal;

and if the difference value between any two voltages is larger than the preset voltage difference value, determining the generated balance starting signal as a second control signal.

Further, the microprocessor is also configured to:

if all the voltages are smaller than a preset first voltage threshold, all the currents are smaller than a preset fourth current threshold, and the highest temperature is smaller than a preset second temperature threshold, determining the generated pre-charging signal as a third control signal;

if each voltage is greater than or equal to a preset first voltage threshold and less than a preset second voltage threshold, each current is greater than or equal to a preset fourth current threshold and less than a preset fifth current threshold, and the highest temperature is less than a preset second temperature threshold, determining the generated main loop switch closing signal as a third control signal;

if each voltage is greater than or equal to a preset second voltage threshold and less than a preset third voltage threshold, each current is greater than or equal to a preset fifth current threshold and less than a preset sixth current threshold, and the highest temperature is less than a preset second temperature threshold, determining the generated pre-discharge signal as a third control signal;

if any voltage is greater than or equal to a preset third voltage threshold, any current is greater than or equal to a preset sixth current threshold, or the highest temperature is greater than or equal to a preset second temperature threshold, determining the generated main loop switch disconnection signal as a third control signal;

the preset fourth current threshold is smaller than the preset first current threshold, the preset fifth current threshold is smaller than the preset second current threshold, the preset sixth current threshold is smaller than the preset third current threshold, and the preset second temperature threshold is smaller than the preset first temperature threshold.

Further, the battery management system further includes: a battery pack equalization circuit;

the battery pack balancing circuit is connected with the analog front-end device, is respectively connected with each battery in the battery pack, and is used for balancing the voltage of each battery when receiving a second control signal which is a balancing start signal and is sent by the analog front-end device.

Further, the battery management system further includes: resetting the chip;

the reset chip is connected with a reset pin of the microprocessor and used for sending a reset signal to the reset pin when detecting the fault of the microprocessor so as to enable the reset pin to be at a low level and reset the microprocessor.

Further, the battery management system further includes: a main loop switch and a pre-charge and discharge module;

the main loop switch is directly connected in series with the main loop, is respectively connected with the microprocessor and the analog front-end device, and is used for being closed when receiving a closing signal of the main loop switch so as to connect the main loop and being opened when receiving an opening signal of the main loop switch so as to disconnect the main loop;

the pre-charging and discharging module is directly connected in series with the main loop, is connected with the main loop switch in parallel, is respectively connected with the microprocessor and the analog front-end device, and is used for closing the pre-charging switch when receiving a pre-charging signal to pre-charge the battery pack, and closing the pre-discharging switch when receiving a pre-discharging signal to pre-discharge the battery pack;

the main circuit switch closing signal, the main circuit switch opening signal, the pre-charge signal and the pre-discharge signal are a first control signal and a third control signal from the microprocessor, and a second control signal from the analog front-end device.

An embodiment of the present invention provides a battery management system, including: the system comprises a battery pack, an electric quantity metering device and a microprocessor; the electric quantity metering device is respectively connected with the battery pack and the microprocessor and is used for detecting the voltage, the current and the temperature information of the battery pack, determining the battery electric quantity of the battery pack and transmitting the battery electric quantity to the microprocessor; the microprocessor is used for generating a first control signal for battery management according to the electric quantity of the battery; the battery pack at least comprises two batteries connected in series, is also connected with the microprocessor and is used for supplying power to the electric quantity metering device and the microprocessor. By adopting the technical scheme, the voltage, the current and the temperature information of the battery pack consisting of the multiple batteries are obtained through the electric quantity metering device, the battery electric quantity of the battery pack is further determined according to the voltage, the current and the temperature information, the battery electric quantity of the battery pack is calculated by taking the battery pack as a whole, the electric quantity calculation precision is improved, the microprocessor is not required to directly receive the working information of each battery in the battery pack for electric quantity calculation, and then the microprocessor generates higher-precision control information according to the battery electric quantity, so that the high-precision management of the multiple-battery pack is realized, the battery management flexibility is improved, and the information processing complexity of the microprocessor is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a battery management system according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of an electric quantity metering device according to a first embodiment of the present invention;

fig. 3 is a schematic structural diagram of a current-voltage sampling module according to a first embodiment of the present invention;

fig. 4 is a schematic structural diagram of a battery management system according to a second embodiment of the present invention;

fig. 5 is a schematic structural diagram of an analog front-end device according to a second embodiment of the present invention;

fig. 6 is a circuit diagram of a battery management system according to a second embodiment of the utility model.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures. In addition, the embodiments and features of the embodiments in the present invention may be combined with each other without conflict.

Example one

Fig. 1 is a schematic structural diagram of a battery management system according to an embodiment of the present invention, in which a battery capacity of a battery pack is determined by a capacity metering device, so that a microprocessor generates a control signal according to the battery capacity to implement charging and discharging management of the battery pack. As shown in fig. 1, the battery management system includes: battery pack 10, fuel gauge 11 and microprocessor 12, wherein:

and the electric quantity metering device 11 is respectively connected with the battery pack 10 and the microprocessor 12 and is used for detecting the voltage, the current and the temperature information of the battery pack 10, determining the battery electric quantity of the battery pack 10 and transmitting the battery electric quantity to the microprocessor 12.

And a microprocessor 12 for generating a first control signal for battery management according to the battery power.

The battery pack 10 at least comprises two batteries 101 connected in series, and is further connected with the microprocessor 12 for supplying power to the electricity metering device 11 and the microprocessor 12.

In the present embodiment, the electricity quantity metering device 11 may be understood as a metering device for calculating and determining the battery electricity quantity of the battery pack 10 according to the acquired information such as the battery current, the voltage and the temperature. The microprocessor 12 may be understood as a central processing unit composed of one or more large scale integrated circuits, where the integrated circuits may perform functions of a control unit and an arithmetic logic unit, and may implement signal interaction with other external devices, and further may generate a corresponding instruction according to the received external information and the logic operation rule, and send the instruction to a corresponding device, so that the corresponding device may perform a corresponding operation according to the received instruction, thereby implementing control of charging and discharging of the battery pack 10. The battery pack 10 may be understood as a power source formed by connecting at least two batteries 101 in series, and optionally, the battery pack 10 in this application may be formed by connecting more than 8 batteries 101 in series, and is applied to a power source in an unmanned aerial vehicle.

Specifically, the battery pack 10 is respectively connected to the electricity metering device 11 and the microprocessor 12 for supplying electricity to the electricity metering device 11 and the microprocessor 12; the electric quantity metering device 11 is respectively in communication connection with the battery pack 10 and the microprocessor 12, the electric quantity metering device 11 collects voltage, current and temperature information of the battery pack 10 through different sampling resistors arranged in the electric quantity metering device 11, wherein the battery pack 10 is regarded as a whole, the collected voltage, current and temperature information are average voltage, average current and average temperature of the battery pack 10, the electric quantity metering device 11 calculates battery electric quantity of the battery pack 10 according to the obtained average voltage, average current and average temperature, and sends the battery electric quantity to the microprocessor 12; the microprocessor 12 generates a first control signal for battery management according to the received battery power and the corresponding relationship between preset power thresholds, and transmits the first control signal to a corresponding hardware module to be controlled through an output interface, thereby implementing control of charging and discharging of the battery pack 10.

Further, fig. 2 is a schematic structural diagram of an electric quantity metering device according to an embodiment of the present invention, wherein the electric quantity metering device 11 includes: a current-voltage sampling module 111, a first temperature sensor 112 and a fuel gauge chip 113.

In this embodiment, the current-voltage sampling module 111 is connected to a pin of the electricity-quantity metering chip 113, and is configured to obtain a sampled voltage and a sampled current of the battery pack 10, and send the sampled voltage and the sampled current to the electricity-quantity metering chip 113.

In this embodiment, the first temperature sensor 112 is disposed at a theoretical average temperature in the battery pack 10, and an output end of the first temperature sensor 112 is connected to a pin of the electric quantity metering chip 113, and is configured to collect an average temperature in the battery pack 10 and send the average temperature to the electric quantity metering chip 113.

In this embodiment, the electric quantity metering chip 113, connected to the current-voltage sampling module 111, the first temperature sensor 112 and the microprocessor 12 through different pins, is configured to determine the battery electric quantity of the battery pack 10 according to the received sampled voltage, sampled current and average temperature, and transmit the battery electric quantity to the microprocessor 12.

The electricity quantity measuring chip 113 is a single battery electricity quantity measuring chip.

Specifically, the input end of the current-voltage sampling module 111 is connected to the battery pack 10 and is configured to obtain a sampling voltage and a sampling current of the battery pack 10, the output end of the current-voltage sampling module 111 is connected to a pin of the electric quantity metering chip 113, and the sampling voltage and the sampling current are sent to the electric quantity metering chip 113 through the pin; the first temperature sensor 112 is disposed at a theoretical average temperature in the battery pack 10, and it can be considered that the temperature collected by the first temperature sensor 112 is an average temperature of each battery 101 in the battery pack 10, an output end of the first temperature sensor 112 is connected to the electric quantity metering chip 113 through a pin, and sends the collected average temperature to the electric quantity metering chip 113 through the pin; the electric quantity metering chip 113 is connected with the microprocessor 12 through pins, and after the battery electric quantity of the battery pack 10 is calculated according to the received sampling voltage, the sampling current and the average temperature, the battery electric quantity is transmitted to the microprocessor 12 through the pins, wherein the pins used for being connected with the current and voltage sampling module 111, the first temperature sensor 112 and the microprocessor 12 in the electric quantity metering chip 113 are all different, and the electric quantity metering chip 113 is a single battery electric quantity metering chip.

In the embodiment of the utility model, the electric quantity metering chip adopted in the electric quantity metering device is a single battery electric quantity metering chip, and the electric quantity metering algorithm with higher precision is realized.

Further, fig. 3 is a schematic structural diagram of a current-voltage sampling module according to an embodiment of the present invention, where the current-voltage sampling module 111 includes: a current detection resistor 111a and a voltage dividing resistor 111 b.

The voltage dividing resistor 111b is connected in parallel to both ends of the battery pack 10, and is used to obtain a sampling voltage.

The current detection resistor 111a is directly connected in series to the main circuit, and is connected in series to one end of the battery pack 10 to obtain a sampling current.

The sampling voltage is a ratio of the output voltage of the battery pack 10 to the number of batteries in the battery pack 10, the sampling current is a current flowing through the battery pack 10, and the main loop is a loop formed by connecting an output positive electrode, a battery pack negative electrode and an output negative electrode.

Specifically, when the main circuit normally works, the voltage dividing resistor 111b is connected in parallel to two ends of the battery pack 10, that is, is connected to the battery pack anode and the battery pack cathode of the battery pack 10, the voltage on the voltage dividing resistor 111b is equal to the voltage at two ends of the battery pack 10, two different pins in the electric quantity metering chip 113 are connected to two ends of the voltage dividing resistor 111b, respectively, and are used for obtaining a sampling voltage acquired by the voltage dividing resistor 111b, where the sampling voltage is a ratio of the voltages at two ends of the battery pack 10 to the number of batteries in the battery pack 10, that is, an average voltage of each battery in the battery pack 10; the current detection resistor 111a is connected in series in the main loop, if one end of the current detection resistor 111a is connected to the positive electrode of the battery pack, the other end is connected to the positive electrode of the output, if one end of the current detection resistor 111a is connected to the negative electrode of the battery pack, the other end is connected to the negative electrode of the output, the current flowing through the current detection resistor 111a is the current of the main loop, that is, the current flowing through each series battery in the battery pack 10, two different pins in the electric quantity measurement chip 113 are respectively connected to two ends of the current detection resistor 111a, and are used for obtaining the sampling current acquired by the current detection resistor 111 a.

Further, the microprocessor 12 is specifically configured to:

if the electric quantity of the battery is larger than a preset first electric quantity threshold value and smaller than a preset second electric quantity threshold value, determining the generated main loop switch closing signal as a first control signal;

if the electric quantity of the battery is larger than a preset second electric quantity threshold value and smaller than a preset third electric quantity threshold value, determining the generated pre-discharge signal as a first control signal;

and if the electric quantity of the battery is greater than a preset third electric quantity threshold value, determining the generated main loop switch disconnection signal as a first control signal.

In the present embodiment, the precharge signal may be understood as a control signal for controlling the battery pack 10 to perform the precharge; the main circuit switch closing signal may be understood as a control signal for controlling the main circuit switch to be closed so that the battery pack 10 can be normally charged and discharged; the pre-discharge signal may be understood as a control signal for controlling the pre-discharge of the battery pack 10; the main circuit switch off signal may be understood as a control signal for controlling the main circuit switch to be turned off so that the battery pack 10 stops charging and discharging.

In this embodiment, the preset first electric quantity threshold, the preset second electric quantity threshold and the preset third electric quantity threshold may be preset electric quantity values corresponding to a control signal for controlling the battery pack.

Specifically, if the electric quantity of the battery is less than the preset first electric quantity threshold, the electric quantity of the current battery pack is considered to be low, and since the battery pack has a high energy ratio, in order to avoid damage to the battery in the battery pack 10, influence on the service life or bring about potential safety hazards, the microprocessor 12 may generate a first control signal whose content is a precharge signal, so that the battery pack 10 enters a precharge state; if the battery capacity is greater than or equal to the preset first capacity threshold and less than the preset second capacity threshold, it is considered that the current battery pack can directly work, and at this time, the microprocessor 12 can generate a first control signal whose content is a main loop switch closing signal, so that the battery pack 10 normally works; if the electric quantity of the battery is greater than or equal to the preset second electric quantity threshold value and less than the preset first electric quantity threshold value, the electric quantity in the current battery pack is considered to be too high, the stability and the storage of the battery are not facilitated, but the degree that the battery needs to stop working immediately is not reached, the microprocessor 12 can generate a first control signal with the content of a pre-discharge signal, so that the battery pack 10 enters a pre-discharge state, the electric quantity of the battery pack 10 is reduced under the condition that the normal working of a loop is not influenced, and potential safety hazards are reduced; if the battery capacity is greater than or equal to the preset third capacity threshold, it may be determined that the current battery capacity in the battery pack is too high, which affects the safety of the circuit operation, and the circuit may not be continuously connected to operate, and the microprocessor 12 may generate the first control signal whose content is the main circuit switch off signal, so that the circuit is disconnected, and the battery pack 10 stops operating.

Example two

Fig. 4 is a schematic structural diagram of a battery management system according to a second embodiment of the present invention, in which the technical solution of this embodiment is further refined on the basis of the above technical solutions, and the battery management system further includes an analog front end device 13, a battery pack equalization circuit 14, a reset chip 15, a main circuit switch 16, and a pre-charge/discharge module 17.

And an analog front end device 13 connected to the battery pack 10 and the microprocessor 12, respectively, for detecting the voltage and current of each battery 101 in the battery pack 10 and the maximum temperature in the battery pack 10, generating a second control signal for battery management based on each voltage, each current and the maximum temperature, and transmitting each voltage, each current and the maximum temperature to the microprocessor 12.

The microprocessor 12 is further configured to generate a third control signal for battery management according to each voltage, each current, and each maximum temperature.

The battery pack balancing circuit 14 is connected to the analog front end device 13, is connected to each of the batteries 101 in the battery pack 10, and is configured to perform voltage balancing on each of the batteries 101 when receiving a second control signal, which is a balancing start signal and is transmitted by the analog front end device 13.

The reset chip 15 is connected to a reset pin of the microprocessor 12, and is configured to send a reset signal to the reset pin when detecting a fault of the microprocessor 12, so that the reset pin is at a low level to reset the microprocessor 12.

The main circuit switch 16 is directly connected in series with the main circuit, and is respectively connected to the microprocessor 12 and the analog front end device 13, and is configured to be closed when receiving a main circuit switch closing signal to connect the main circuit, and to be opened when receiving a main circuit switch opening signal to open the main circuit.

The pre-charge and discharge module 17 is directly connected in series to the main circuit, is connected in parallel to the main circuit switch 16, and is connected to the microprocessor 12 and the analog front-end device 13, respectively, for closing the pre-charge switch when receiving a pre-charge signal, pre-charging the battery pack 10, and closing the pre-discharge switch when receiving a pre-discharge signal, pre-discharging the battery pack 10.

The main circuit switch closing signal, the main circuit switch opening signal, the pre-charge signal and the pre-discharge signal are a first control signal and a third control signal from the microprocessor 12, and a second control signal from the analog front end device 13.

Specifically, the analog front-end device 13 is connected to each battery 101 in the battery pack 10 through a wire, and is configured to detect a voltage and a current corresponding to each battery 101 in the battery pack 10 and a highest temperature in the battery pack 10 by a resistance sampling method, determine a loop and an operating state of the battery pack 10 according to each voltage, each current and the highest temperature, and generate a second control signal for battery management according to the operating state; the output port of the analog front-end device 13 is further connected to the input port of the microprocessor 12 through a wire, and is configured to transmit the acquired voltages, currents, and maximum temperature to the microprocessor 12. Accordingly, the microprocessor 12 may generate a third control signal for battery management according to the received voltages, currents and the maximum temperature and according to preset control conditions therein.

Specifically, the battery pack balancing circuit 14 is connected to each battery 101 in the battery pack 10 and the analog front end device 13 through different IO ports, and is configured to perform voltage balancing on each connected battery 101 when receiving a second control signal sent by the analog front end device 13, where the second control signal is a balancing start signal, so that the problem that voltages of the batteries 101 are inconsistent due to large-current flight when the battery pack 10 does not operate can be solved. Optionally, the battery equalization circuit 14 may be a set of an equalization circuit and a voltage acquisition circuit, which is not limited in this embodiment of the present invention.

Specifically, the reset chip 15 may be a reset IC chip, and is connected to a reset pin of the microprocessor 12 through an IO port, and when a fault of the microprocessor 12 is detected, the reset chip 15 sends a reset signal to the reset pin, so that the reset pin is at a low level to reset the microprocessor 12. The reset chip 15 can better solve the problem that the microprocessor 12 crashes due to the rotation of the unmanned aerial vehicle which is suddenly high or low during flying when the battery pack 10 is applied to the unmanned aerial vehicle.

Specifically, the main circuit switch 16 is directly connected in series to the main circuit, one end of the main circuit switch is connected to the positive electrode or the negative electrode of the battery pack 10, the other end of the main circuit switch is connected to the output positive electrode or the output negative electrode, an input port of the main circuit switch 16 is connected to output ports of the microprocessor 12 and the analog front-end device 13 through wires, and is configured to receive a first control signal, a second control signal, or a third control signal sent by the microprocessor 12 and the analog front-end device 13, when the received control signal is a main circuit switch closing signal, the main circuit switch 16 is closed to connect the main circuit, and when the received control signal is a main circuit switch opening signal, the main circuit switch 16 is opened to disconnect the main circuit.

Specifically, the pre-charging and discharging module 17 is directly connected in series to the main loop, one end of the pre-charging and discharging module is connected to the anode or the cathode of the battery pack 10, the other end of the pre-charging and discharging module is connected to the output anode or the output cathode, and is connected in parallel to the main loop switch 16, the input port of the pre-charging and discharging module 17 is also connected to the output ports of the microprocessor 12 and the analog front-end device 13 through wires, respectively, and is configured to receive a first control signal, a second control signal, or a third control signal sent by the microprocessor 12 and the analog front-end device 13, and when the received control signal is a pre-charging signal, the pre-charging and discharging module 17 controls the pre-charging switch to be closed, so as to pre-charge the battery pack 10; when the received control signal is a pre-discharge signal, the pre-charge-discharge module 17 controls the pre-discharge switch to be closed, so as to pre-discharge the battery pack 10.

It should be understood that the power communication output shown in fig. 4 is the output between the output positive pole and the output negative pole, and the output content can be provided by any module of the battery pack 10, the electricity quantity metering device 11, the microprocessor 12, the main circuit switch 16 and the pre-charge/discharge module 17.

Further, fig. 5 is a schematic structural diagram of an analog front-end device according to a second embodiment of the present invention, wherein the analog front-end device 13 includes: a second temperature sensor 131 and an analog front-end chip 132.

In this embodiment, the second temperature sensor 131 is disposed at a theoretical highest temperature in the battery pack 10, and an output end of the second temperature sensor 131 is connected to a pin of the analog front-end chip 132, and is configured to collect the highest temperature in the battery pack 10 and send the highest temperature to the analog front-end chip 132.

In the present embodiment, the analog front-end chip 132 is connected to the second temperature sensor 131, the microprocessor 12 and the positive terminals of the batteries 101 in the battery pack 10 through different pins, and is configured to generate a second control signal for battery management according to the received maximum temperature and the acquired voltage and current of each battery 101 in the battery pack 10, and transmit each voltage, each current and the maximum temperature to the microprocessor 12.

Specifically, the second temperature sensor 131 is disposed at a theoretical highest temperature in the battery pack 10, and it can be considered that the temperature collected by the second temperature sensor 131 is the highest temperature in the battery pack 10, that is, the collected highest temperature can be used as an alert temperature of the battery pack 10, an output end of the second temperature sensor 131 is connected to a pin of the analog front-end chip 132, and the highest temperature can be sent to the analog front-end chip 132 through the connection; the analog front-end chip 132 is respectively connected with the second temperature sensor 131, the microprocessor 12 and the positive terminal of each battery 101 in the battery pack 10 through different pins, obtains the voltage and current corresponding to each battery by a resistance sampling method through the connection with each battery 101, directly obtains the highest temperature collected by the second temperature sensor 131 through the connection with the second temperature sensor 131, and generates a second control signal for battery management according to each voltage, each current, the highest temperature and a circuit protection evaluation standard preset in the analog front-end chip 132; an output pin of the analog front-end chip 132 is connected to an input port of the microprocessor 12 through a wire, and is used for transmitting the acquired voltages, currents and the maximum temperature to the microprocessor 12.

Further, the analog front-end chip 132 is specifically configured to:

Specifically, if each current is smaller than a preset first current threshold and the highest temperature is smaller than a preset first temperature threshold, it can be considered that the electric quantity of a part of the batteries in the battery pack 10 is lower and within a safe working temperature range, the analog front-end chip 132 can generate a second control signal whose content is a precharge signal, so that the battery pack 10 enters a precharge state; if each current is greater than or equal to the preset first current threshold and less than the preset second current threshold, and the highest temperature is less than the preset first temperature threshold, it can be considered that the current electric quantity of the battery pack can support normal operation and is within the safe operating temperature range, and at this time, the analog front-end chip 132 can generate a second control signal whose content is a main loop switch closing signal, so that the battery pack 10 normally operates; if each current is greater than or equal to the second preset current threshold and less than the preset third current threshold, and the highest temperature is less than the preset first temperature threshold, it may be considered that the electric quantity of a part of the batteries in the current battery pack 10 is too high, which may affect the safety of the loop operation, but the current battery pack 10 does not reach the degree of stopping immediately, and the current battery pack 10 has a temperature within the safe operating temperature range, at this time, the analog front-end chip 132 may generate a second control signal whose content is a pre-discharge signal, so that the battery pack 10 enters a pre-discharge state, so as to reduce the electric quantity of the battery pack 10 without affecting the normal operation of the loop, and reduce potential safety hazards; if any current is greater than or equal to the preset third current threshold, or the highest temperature is greater than or equal to the preset first temperature threshold, it can be considered that the current of one or more batteries 101 in the current battery pack 10 is too large, and there is a possibility of overcurrent or short-circuit fault, or the current temperature of the battery pack 10 exceeds the safe working temperature range, which has affected the working safety of the loop, and the loop cannot be continuously connected for working, at this time, the analog front-end chip 132 can generate a second control signal whose content is a main loop switch off signal, so that the loop is disconnected, and the battery pack 10 stops working; if the voltage difference between any two batteries 101 in the battery pack 10 is greater than the preset voltage difference, it may be determined that the voltages of the batteries 101 in the battery pack 10 are unbalanced, and at this time, the analog front-end chip 132 may generate a second control signal whose content is an equalization start signal, and send the second control signal to the battery pack equalization circuit 14 through a corresponding pin, so that the battery pack equalization circuit 14 performs voltage equalization on each battery 101 in the battery pack 10.

Accordingly, the microprocessor 12 is also configured to:

if any voltage is greater than or equal to a preset third voltage threshold, any current is greater than or equal to a preset sixth current threshold, or the highest temperature is greater than a preset second temperature threshold, determining the generated main loop switch disconnection signal as a third control signal;

Specifically, if each voltage is smaller than a preset first voltage threshold, each current is smaller than a preset fourth current threshold, and the highest temperature is smaller than a preset second temperature threshold, it can be considered that the electric quantity of a part of the batteries in the battery pack 10 is lower and within a safe working temperature range, at this time, the microprocessor 12 can generate a third control signal whose content is a precharge signal, so that the battery pack 10 enters a charging state; if each voltage is greater than or equal to a preset first voltage threshold and less than a preset second voltage threshold, each current is greater than or equal to a preset fourth current threshold and less than a preset fifth current threshold, and the highest temperature is less than a preset second temperature threshold, it can be considered that the voltage and the current of each battery 101 in the current battery pack 10 can support the normal operation of the loop, and the temperature of the whole battery pack 10 is within a safe operating temperature range, at this time, the microprocessor 12 can generate a third control signal whose content is a main loop switch closing signal, so that the battery pack 10 operates normally; if each voltage is greater than or equal to the preset second voltage threshold and less than the preset third voltage threshold, each current is greater than or equal to the preset fifth current threshold and less than the preset sixth current threshold, and the highest temperature is less than the preset second temperature threshold, it can be considered that the electric quantity of a part of batteries in the battery pack 10 is too high, or the voltage and the current of a part of batteries are too high, which may affect the safety of the loop operation, but does not reach the degree of stopping the operation immediately, and the temperature of the battery pack 10 is within the safe operating temperature range, at this time, the microprocessor 12 can generate a third control signal whose content is a pre-discharge signal, so that the battery pack 10 enters a pre-discharge state, so as to reduce the electric quantity of the batteries 101 with high voltage and high current in the battery pack 10 without affecting the normal operation of the loop, and reduce potential safety hazards; if any voltage is greater than or equal to the preset third voltage threshold, any current is greater than or equal to the preset sixth current threshold, or the highest temperature is greater than the preset second temperature threshold, it can be considered that the current or voltage of one or more batteries 101 in the current battery pack 10 is too large, and there is a possibility of overcurrent or short-circuit fault, or the current temperature of the battery pack 10 exceeds the safe working temperature range, which affects the working safety of the loop and cannot continue to connect the loop for working, at this time, the microprocessor 12 can generate a third control signal whose content is a main loop switch off signal, so that the loop is disconnected, and the battery pack 10 stops working. Further, the preset fourth current threshold is smaller than the preset first current threshold, the preset fifth current threshold is smaller than the preset second current threshold, the preset sixth current threshold is smaller than the preset third current threshold, and the preset second temperature threshold is smaller than the preset first temperature threshold, which indicates that the condition for generating the same control signal by the microprocessor 12 is lower than that of the analog front-end chip 132, that is, the analog front-end chip 132 is mainly used for circuit protection, and the microprocessor 12 generates the control signal according to actual requirements, so as to realize flexible management of charging and discharging of the battery pack.

Fig. 6 is a circuit example diagram of a battery management system according to a second embodiment of the present invention, and the circuit shown in fig. 6 is only an example diagram of the architecture of the battery management system of the present application, and is not a specific schematic diagram, where parts of components are omitted and the pin sequence is not exactly the same as that of an actual device. BAT +, BAT-, PACK +, PACK-, and RX/TX are respectively a battery PACK anode, a battery PACK cathode, an output anode, an output cathode and a communication port of the battery PACK; q1 and Q2 are main loop switches NMOS for battery management, respectively, and Q3 and Q4 are pmos switches in the pre-charge and discharge module for battery management, respectively, for controlling pre-charge and pre-discharge of the battery pack; CELL1 and CELL2 … are batteries connected in series in the battery pack.

In the above example, U1 is a battery gauge chip for calculating the battery capacity of the battery pack, and the single battery gauge chip BQ27Z561 is taken as an example in the present application, and U1 is connected to the battery pack through a first pin to receive the power supply of the battery pack; r1 and R2 are voltage dividing resistors of the battery pack, are respectively connected with a third pin and a seventh pin of U1 and are used for collecting the voltage of the battery pack and calculating the electric quantity of the battery pack as a whole; the SENSE is a current detection resistor connected in series in the main loop, and two ends of the SENSE are respectively connected with a fourth pin and a fifth pin of the U1 to collect the current of each battery of the battery pack; the RT1 is a temperature sensor arranged at the theoretical average temperature in the battery pack and connected with the fifth pin of the U1, and is used for transmitting the acquired average temperature of the battery pack to the U1; the second pin of U1 is connected to the second pin of microprocessor U2 for communication between U1 and U2.

In the above example, U2 is a microprocessor, and is mainly used to generate control signals according to the received battery voltage, current, power and temperature information, so as to control the functions of the battery and the internal and external communication. The first pin of the U2 is connected with the ninth pin of the analog front-end chip U3 for realizing intercommunication with the U3; a second pin of the U2 is connected with a second pin of the U1, so as to realize mutual communication between the U1 and the U2; the third pin of the U2 is connected with the input ports of devices such as Q1, Q2, Q3 and Q4, and is used for transmitting other logic control information to corresponding devices; a fourth pin of the U2 is connected with an external communication port RX/TX for external communication; the fifth pin of U2 is the ground terminal; a sixth pin of the U2 is connected with the battery pack and used for receiving power supply of the battery pack; the seventh pin of the U2 is a reset pin, and is connected to the reset chip U4 for receiving the reset signal of the U4 during a fault.

In connection with the above example, U3 is an analog front-end chip, and is used to detect the voltage and current of each battery in the battery pack, implement overcurrent and short-circuit protection for the battery pack, and control the pre-charge and pre-discharge MOS switches according to the preset conditions, and the BQ76952 chip is taken as an example in this application for description. The U3 is respectively connected with the input ports of Q1, Q2, Q3 and Q4 through a first pin, a second pin, a fourteenth pin and a thirteenth pin, and is used for sending the generated control signals to corresponding devices; the third pin, the fourth pin and the fifth pin of the U3 are respectively connected with the sixth pin, the fifth pin and the fourth pin of the equalization circuit U5, so as to receive voltage information of different batteries in the battery pack and send the generated equalization start signal to the U5 through the corresponding pins when necessary; a sixth pin and a seventh pin of the U3 are respectively connected with two ends of the SENSE and used for collecting the current of each battery of the battery pack; the eighth pin of U3 is the ground terminal; the ninth pin of U3 is connected with the first pin of U2 to realize the intercommunication between U2 and U3; a tenth pin of the U3 is connected with the battery pack and used for receiving power supply of the battery pack; the eleventh pin of U3 is connected with the sixth pin of U4 to realize intercommunication between U3 and U4; the twelfth pin of U3 is connected to a temperature sensor RT2, which is located at the theoretical highest temperature within the battery pack, to obtain the highest temperature of the battery pack.

In the above example, U4 is a reset chip, which is used to reset U2 when the microprocessor U2 is in a crash fault due to the rotation of the motor that is suddenly high or low during the flight of the unmanned aerial vehicle. The first pin of U4 is connected with the seventh pin of U2 to send a reset signal to U2 when it fails; the second pin of U4 is used for receiving the reset input signal of U2; the fifth pin of U4 is the ground terminal; the sixth pin of U4 is connected to the eleventh pin of U3 for enabling intercommunication between U3 and U4.

In connection with the above example, U5 is an equalizing circuit for collecting the voltage of each battery in the battery pack, and when the battery pack is not in operation, the problem of inconsistent voltage of each battery in the battery pack due to large-current flight of the unmanned aerial vehicle is solved according to the received equalizing start signal. The first pin, the second pin and the third pin of the U5 are respectively connected with the positive poles of different batteries in the battery pack; the fourth pin, the fifth pin and the sixth pin of U5 are connected with the fifth pin, the fourth pin and the third pin of U3 respectively.

The battery management system provided by the embodiment introduces the single battery electric quantity metering chip on the basis of the existing management method for the battery pack consisting of multiple batteries, performs battery electric quantity calculation on the battery pack as a whole by combining with a high-precision electric quantity metering algorithm of the single battery electric quantity metering chip, further enables the microprocessor to generate a higher-precision control signal according to the high-precision battery electric quantity, introduces the reset chip, enables the microprocessor to be reset and started in time when a fault occurs, realizes high-precision and high-safety management on the multi-battery pack, improves the flexibility of battery management, and reduces the information processing complexity of the microprocessor.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the utility model. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A battery management system, comprising: the system comprises a battery pack, an electric quantity metering device and a microprocessor;

2. The system of claim 1, wherein the fuel gauge device comprises: the device comprises a current and voltage sampling module, a first temperature sensor and an electric quantity metering chip;

the first temperature sensor is arranged at the theoretical average temperature in the battery pack, and the output end of the first temperature sensor is connected with a pin of the electric quantity metering chip and used for collecting the average temperature in the battery pack and sending the average temperature to the electric quantity metering chip;

the electric quantity metering chip is connected with the current and voltage sampling module, the first temperature sensor and the microprocessor through different pins respectively, and is used for determining the battery electric quantity of the battery pack according to the received sampling voltage, the received sampling current and the received average temperature and transmitting the battery electric quantity to the microprocessor;

the electric quantity metering chip is a single battery electric quantity metering chip.

3. The system of claim 2, wherein the current-voltage sampling module comprises:

current detection resistance and divider resistance, wherein:

the voltage dividing resistor is connected to two ends of the battery pack in parallel and used for acquiring the sampling voltage, and the sampling voltage is the ratio of the output voltage of the battery pack to the number of batteries in the battery pack;

the current detection resistance directly establishes ties in the major loop, with the one end series connection of group battery is used for acquireing sampling current, sampling current is for flowing through the electric current of group battery, the major loop is that the return circuit that formation is connected to output positive pole, group battery negative pole and output negative pole.

4. The system of claim 1, wherein the microprocessor is specifically configured to:

if the battery electric quantity is smaller than a preset first electric quantity threshold value, determining the generated pre-charging signal as the first control signal;

if the battery electric quantity is greater than or equal to the preset first electric quantity threshold value and smaller than a preset second electric quantity threshold value, determining the generated main loop switch closing signal as the first control signal;

if the battery electric quantity is greater than or equal to the preset second electric quantity threshold and less than a preset third electric quantity threshold, determining the generated pre-discharge signal as the first control signal;

and if the battery electric quantity is greater than or equal to the preset third electric quantity threshold value, determining the generated main loop switch disconnection signal as the first control signal.

5. The system of claim 1, further comprising: an analog front end device;

correspondingly, the microprocessor is further configured to generate a third control signal for battery management according to each of the voltages, each of the currents, and each of the maximum temperatures.

6. The system of claim 5, wherein the analog front end device comprises: a second temperature sensor and an analog front-end chip;

the second temperature sensor is arranged at the theoretical highest temperature position in the battery pack, and the output end of the second temperature sensor is connected with the pin of the analog front-end chip and used for collecting the highest temperature in the battery pack and sending the highest temperature to the analog front-end chip;

the analog front-end chip is connected with the second temperature sensor, the microprocessor and the positive terminals of the batteries in the battery pack through different pins respectively, and is used for generating a second control signal for battery management according to the received highest temperature and the acquired voltage and current of the batteries in the battery pack and transmitting the voltage, the current and the highest temperature to the microprocessor.

7. The system of claim 6, wherein the analog front-end chip is specifically configured to:

if the currents are smaller than a preset first current threshold and the highest temperature is smaller than a preset first temperature threshold, determining the generated pre-charging signal as the second control signal;

if the current is greater than or equal to the preset first current threshold and less than a preset second current threshold, and the highest temperature is less than the preset first temperature threshold, determining the generated main loop switch closing signal as the second control signal;

if the current is greater than or equal to the preset second current threshold and less than a preset third current threshold, and the highest temperature is less than the preset first temperature threshold, determining the generated pre-discharge signal as the second control signal;

if any current is greater than or equal to the preset third current threshold value, or the highest temperature is greater than or equal to the preset first temperature threshold value, determining the generated main loop switch disconnection signal as the second control signal;

and if the difference value between any two voltages is larger than a preset voltage difference value, determining the generated balance starting signal as the second control signal.

8. The system of claim 7, wherein the microprocessor is further configured to:

if the voltages are smaller than a preset first voltage threshold, the currents are smaller than a preset fourth current threshold, and the highest temperature is smaller than a preset second temperature threshold, determining the generated pre-charge signal as the third control signal;

if each voltage is greater than or equal to the preset first voltage threshold and less than the preset second voltage threshold, each current is greater than or equal to the preset fourth current threshold and less than the preset fifth current threshold, and the highest temperature is less than the preset second temperature threshold, determining the generated main loop switch closing signal as the third control signal;

if each voltage is greater than or equal to the preset second voltage threshold and less than a preset third voltage threshold, each current is greater than or equal to the preset fifth current threshold and less than a preset sixth current threshold, and the maximum temperature is less than a preset second temperature threshold, determining the generated pre-discharge signal as the third control signal;

if any voltage is greater than or equal to a preset third voltage threshold, any current is greater than or equal to a preset sixth current threshold, or the highest temperature is greater than a preset second temperature threshold, determining a generated main loop switch disconnection signal as the third control signal;

9. The system of claim 5, further comprising: a battery pack equalization circuit;

the battery pack balancing circuit is connected with the analog front-end device, is respectively connected with each battery in the battery pack, and is used for balancing the voltage of each battery when receiving the second control signal which is a balancing start signal and is sent by the analog front-end device.

10. The system of claim 1, further comprising: resetting the chip;

the reset chip is connected with a reset pin of the microprocessor and used for sending a reset signal to the reset pin when the fault of the microprocessor is detected, so that the reset pin is at a low level to reset the microprocessor.

11. The system of any of claims 1-10, further comprising: a main loop switch and a pre-charge and discharge module;

the main loop switch is directly connected in series with the main loop, is respectively connected with the microprocessor and the analog front-end device, and is used for being closed when receiving a main loop switch closing signal so as to connect the main loop and being opened when receiving a main loop switch opening signal so as to disconnect the main loop;