WO2022237817A1

WO2022237817A1 - Battery management system

Info

Publication number: WO2022237817A1
Application number: PCT/CN2022/092126
Authority: WO
Inventors: 秦威
Original assignee: 深圳市道通智能航空技术股份有限公司
Priority date: 2021-05-11
Filing date: 2022-05-11
Publication date: 2022-11-17
Also published as: CN113103922A

Abstract

A battery management system, comprising: a battery pack (10), a fuel gauge device (11), and a microprocessor (12). The fuel gauge device (11) is connected to the battery pack (10) and the microprocessor (12) respectively and is configured to measure voltage, current and temperature information of the battery pack (10), determine battery power of the battery pack (10), and transmit the battery power to the microprocessor (12). The microprocessor (12) is configured to generate 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 to the microprocessor (12) to supply power to the fuel gauge device (11) and the microprocessor (12). The battery management system calculates the battery power of the battery pack (10) by using the battery pack (10) as a whole, thereby improving power calculation precision, implementing high-precision management of a multi-battery pack, improving battery management flexibility, and reducing information processing complexity of the microprocessor (12).

Description

A battery management system

This application claims the priority of the Chinese patent application with the application number 2021105098504 and the application title "a battery management system" filed with the China Patent Office on May 11, 2021, the entire contents of which are incorporated in this application by reference.

technical field

Embodiments of the present invention relate to the technical field of battery management, and in particular, to a battery management system.

Background technique

With the gradual rise of agricultural drones, the demand for power of drones is also increasing day by day. The increase in power means an increase in the number of batteries in the battery pack, and due to limitations in technology and product structure, there are not many multi-battery management solutions for drones at present.

At present, for the management of the battery pack formed by connecting multiple batteries in the UAV, each battery in the battery pack is often managed independently through the UAV microprocessor to obtain information such as current, voltage, and temperature corresponding to each battery, and then determine each battery. Battery power and adjust the charging and discharging of different batteries.

However, in the existing management technology, each battery in the battery pack is not considered as a whole. Individual control requires a large amount of calculation and many errors, which increases the complexity of multi-battery battery pack management, and it is difficult to achieve flexible and high-precision battery management.

Contents of the invention

The present invention provides a battery management system to realize high-precision management of multi-battery series battery packs, so that the accuracy of battery pack electricity can meet the safety requirements of drones, improve the flexibility of battery management, and reduce management complexity.

An embodiment of the present invention provides a battery management system, including: a battery pack, a power meter and a microprocessor;

The power metering device is connected with the battery pack and the microprocessor respectively, and is used to detect the voltage, current and temperature information of the battery pack, determine the battery power of the battery pack, and transmit the battery power to the microprocessor;

a microprocessor for generating a first control signal for battery management according to the battery level;

The battery pack includes at least two batteries connected in series, and is also connected with the microprocessor for supplying power to the electricity metering device and the microprocessor.

Further, the power metering device includes: a current and voltage sampling module, a first temperature sensor and a power metering chip;

The current and voltage sampling module is connected to the pins of the power metering chip, and is used to obtain the sampling voltage and sampling current of the battery pack, and send the sampling voltage and sampling current to the power metering chip;

The first temperature sensor is set at the theoretical average temperature in the battery pack. The output end of the first temperature sensor is connected to the pin of the power metering chip for collecting the average temperature in the battery pack and sending the average temperature to the power metering chip. ;

The power metering chip is connected with the current and voltage sampling module, the first temperature sensor and the microprocessor respectively through different pins, and is used to determine the battery power of the battery pack according to the received sampling voltage, sampling current and average temperature, and to calculate the battery power passed to the microprocessor;

Wherein, the power metering chip is a single battery power metering chip.

Further, the current and voltage sampling module includes:

current sense resistors and voltage divider resistors, where:

The voltage dividing resistors are connected in parallel to both ends of the battery pack to obtain a sampling voltage, which 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 circuit and connected in series with one end of the battery pack to obtain the sampling current. The sampling current is the current flowing through the battery pack. The main circuit is connected to the output positive pole, the battery pack positive pole, the battery pack negative pole and the output negative pole. formed circuit.

Further, the microprocessor is specifically used for:

If the battery power is less than the preset first power threshold, the generated pre-charge signal is determined as the first control signal;

If the battery power is greater than or equal to the preset first power threshold and less than the preset second power threshold, the generated main circuit switch closing signal is determined as the first control signal;

If the battery power is greater than or equal to the preset second power threshold and less than the preset third power threshold, the generated pre-discharge signal is determined as the first control signal;

If the battery power is greater than or equal to the preset third power threshold, the generated main loop switch disconnection signal is determined as the first control signal.

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

The analog front-end device is connected with the battery pack and the microprocessor respectively, and is used to detect the voltage and current of each battery in the battery pack and the highest temperature in the battery pack, and generate the first battery management signal according to each voltage, each current and the highest temperature. 2. Control signals, and transmit each voltage, each current and the highest temperature to the microprocessor;

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

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

The second temperature sensor is set at the theoretical maximum temperature in the battery pack, and the output terminal of the second temperature sensor is connected to the pin of the analog front-end chip to collect the highest temperature in the battery pack and send the highest temperature to the analog front-end chip ;

The analog front-end chip is connected to the second temperature sensor, the microprocessor and the positive terminals of each battery in the battery pack through different pins, and is used to generate The second control signal is used for battery management, and transmits each voltage, each current and the maximum temperature to the microprocessor.

Further, the analog front-end chip is specifically used for:

If each current is less than the preset first current threshold and the highest temperature is less than the preset first temperature threshold, the generated pre-charge signal is determined as the second control signal;

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, the generated main circuit switch closing signal is determined as the second control signal;

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

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, the generated main circuit switch disconnection signal is determined as the second control signal;

If the difference between any two voltages is greater than the preset voltage difference, the generated equalization enable signal is determined as the second control signal.

Further, the microprocessor is also used for:

If each voltage is less than a preset first voltage threshold, each current is less than a preset fourth current threshold, and the highest temperature is less than a preset second temperature threshold, the generated pre-charging signal is determined as a 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 lower than the preset first threshold. Two temperature thresholds, determining the generated main circuit 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 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 third threshold. Two temperature thresholds, determining the generated pre-discharge signal as the third control signal;

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 or equal to the preset second temperature threshold, the generated main circuit switch disconnection signal is determined is the third control signal;

Wherein, 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 less than the preset first temperature threshold.

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

The battery pack equalization circuit is connected to the analog front-end device and to each battery in the battery pack, and is used to perform voltage balance on each battery when receiving a second control signal sent by the analog front-end device, which is a balance start signal.

Further, the battery management system also includes: a reset chip;

The reset chip is connected to the reset pin of the microprocessor, and is used for sending a reset signal to the reset pin when detecting a failure of the microprocessor, so that the reset pin is at a low level to reset the microprocessor.

Further, the battery management system also includes: a main circuit switch and a pre-charging and discharging module;

The main circuit switch is directly connected in series with the main circuit, and is respectively connected with the microprocessor and the analog front-end device, and is used to close when receiving the closing signal of the main circuit switch, so as to connect the main circuit, and to connect the main circuit when receiving the disconnecting signal of the main circuit switch When disconnected, so that the main circuit is disconnected;

The pre-charge and discharge module is directly connected in series with the main circuit, connected in parallel with the main circuit switch, and connected with the microprocessor and the analog front-end device respectively, and is used to close the pre-charge switch when receiving the pre-charge signal, and pre-charge the battery pack. And close the pre-discharge switch when receiving the pre-discharge signal, and pre-discharge the battery pack;

Among them, the main circuit switch closing signal, the main circuit switch opening signal, the pre-charging signal and the pre-discharging signal are the first control signal and the third control signal from the microprocessor, and the second control signal from the analog front-end device Signal.

An embodiment of the present invention provides a battery management system, including: a battery pack, a power metering device and a microprocessor; the power metering device is connected to the battery pack and the microprocessor respectively, and is used to detect the voltage, current and temperature of the battery pack information, determine the battery power of the battery pack, and deliver the battery power to the microprocessor; the microprocessor is used to generate a first control signal for battery management according to the battery power; the battery pack includes at least two batteries connected in series, and Connected with the microprocessor, it is used to supply power to the electricity metering device and the microprocessor. By adopting the above technical scheme, the voltage, current and temperature information of the battery pack composed of multiple batteries is obtained through the power metering device, and then the battery power of the battery pack is determined according to the above voltage, current and temperature information, and the battery pack is taken as a whole to calculate its battery capacity. Power, which improves the accuracy of power calculation, without the need for the microprocessor to directly receive the working information of each battery in the battery pack for power calculation, which in turn enables the microprocessor to generate higher-precision control information based on the battery power, and realizes the control of multi-battery battery packs. High-precision management improves the flexibility of battery management and reduces the complexity of microprocessor information processing.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus It should be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

FIG. 1 is a schematic structural diagram of a battery management system in Embodiment 1 of the present invention;

Fig. 2 is a schematic structural diagram of a power metering device in Embodiment 1 of the present invention;

3 is a schematic structural diagram of a current and voltage sampling module in Embodiment 1 of the present invention;

FIG. 4 is a schematic structural diagram of a battery management system in Embodiment 2 of the present invention;

5 is a schematic structural diagram of an analog front-end device in Embodiment 2 of the present invention;

FIG. 6 is an example circuit diagram of a battery management system in Embodiment 2 of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings but not all structures. In addition, the embodiments and the features in the embodiments of the present invention can be combined with each other under the condition of no conflict.

Embodiment one

Fig. 1 is a schematic structural diagram of a battery management system provided by Embodiment 1 of the present invention. The battery power of the battery pack is determined by the power metering device, and then the microprocessor generates a control signal according to the battery power to realize charge and discharge management of the battery pack. . As shown in Figure 1, the battery management system includes: a battery pack 10, a power meter 11 and a microprocessor 12, wherein:

The power metering device 11 is connected to the battery pack 10 and the microprocessor 12 respectively, and is used to detect the voltage, current and temperature information of the battery pack 10, determine the battery power of the battery pack 10, and transmit the battery power to the microprocessor 12.

The microprocessor 12 is configured to generate a first control signal for battery management according to the battery power.

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

In this embodiment, the power metering device 11 can be understood as a metering device for calculating and determining the battery power of the battery pack 10 according to the acquired battery current, voltage, temperature and other information. Microprocessor 12 can be understood as a central processing unit composed of one or several large-scale integrated circuits, where the integrated circuits can perform the functions of control components and arithmetic logic components, and can realize signal interaction with other external devices, and then can according to The received external information and logical operation rules generate corresponding instructions, and send the instructions to corresponding devices, so that the corresponding devices perform corresponding operations according to the received instructions to realize the control of charging and discharging of the battery pack 10 . The battery pack 10 can be understood as a power supply composed of at least two batteries 101 connected in series. Optionally, the battery pack 10 in this application can be composed of more than 8 batteries 101 connected in series, and is used as a power supply in drones.

Specifically, the battery pack 10 is respectively connected to the power metering device 11 and the microprocessor 12 for supplying power to the power metering device 11 and the microprocessor 12 respectively; the power metering device 11 communicates with the battery pack 10 and the microprocessor 12 respectively connected, the power metering device 11 collects the voltage, current and temperature information of the battery pack 10 through different sampling resistors arranged therein, wherein the battery pack 10 is regarded as a whole, and the collected voltage, current and temperature information are the battery pack 10 The average voltage, average current and average temperature of the electricity metering device 11 calculates the battery power of the battery pack 10 according to the obtained average voltage, average current and average temperature, and sends the battery power to the microprocessor 12; the microprocessor 12 according to The corresponding relationship between the received battery power level and the preset power threshold value generates the first control signal for battery management, and transmits the first control signal to the corresponding hardware module that needs to be controlled through the output interface to realize Controlling the charging and discharging of the battery pack 10 .

Further, FIG. 2 is a schematic structural diagram of a power metering device provided by Embodiment 1 of the present invention, wherein the power metering device 11 includes: a current and voltage sampling module 111 , a first temperature sensor 112 and a power metering chip 113 .

In this embodiment, the current and voltage sampling module 111 is connected to the pins of the power metering chip 113 for acquiring the sampled voltage and current of the battery pack 10 and sending the sampled voltage and current to the power metering chip 113 .

In this embodiment, the first temperature sensor 112 is set at the theoretical average temperature in the battery pack 10, and the output terminal of the first temperature sensor 112 is connected to the pin of the power metering chip 113 for collecting the average temperature in the battery pack 10. temperature, and send the average temperature to the power metering chip 113.

In this embodiment, the electricity metering chip 113 is connected to the current and voltage sampling module 111, the first temperature sensor 112 and the microprocessor 12 through different pins, and is used to determine the The battery power of the battery pack 10 is transmitted to the microprocessor 12 .

Wherein, the power metering chip 113 is a single battery power metering chip.

Specifically, the input terminal of the current and voltage sampling module 111 is connected to the battery pack 10 for obtaining the sampling voltage and current of the battery pack 10, and the output terminal of the current and voltage sampling module 111 is connected to the pin of the power metering chip 113, through the above-mentioned The pin sends the sampled voltage and sampled current to the power metering chip 113; the first temperature sensor 112 is set at the theoretical average temperature in the battery pack 10, and it can be considered that the temperature collected by the first temperature sensor 112 is the temperature in the battery pack 10. For the average temperature of each battery 101, the output end of the first temperature sensor 112 is connected to the power metering chip 113 through a pin, and the average temperature collected is sent to the power metering chip 113 through the pin; The processor 12 is connected through pins, and after calculating the battery power of the battery pack 10 according to the received sampling voltage, sampling current and average temperature, the battery power is transmitted to the microprocessor 12 through the pin, wherein the power meter The pins in the chip 113 used to connect with the current and voltage sampling module 111 , the first temperature sensor 112 and the microprocessor 12 are all different, and the fuel gauge chip 113 is a single battery fuel gauge chip.

In the embodiment of the present invention, since the power metering chip used in the power metering device is a single-cell power metering chip, which has a higher-precision power metering algorithm, the battery pack composed of multiple batteries in series is used as a whole to use the power of a single battery. The metering chip calculates the battery power, so that the calculated battery power has higher accuracy, and then enables the microprocessor to determine the first control signal that is more suitable for battery management according to the battery power, thereby improving the effectiveness of battery management.

Further, FIG. 3 is a schematic structural diagram of a current and voltage sampling module provided in Embodiment 1 of the present invention, wherein the current and voltage sampling module 111 includes: a current detection resistor 111a and a voltage dividing resistor 111b.

The voltage dividing resistor 111b is connected in parallel to both ends of the battery pack 10 for obtaining the sampling voltage.

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

Wherein, the sampling voltage is the ratio of the output voltage of the battery pack 10 to the number of batteries in the battery pack 10, the sampling current is the current flowing through the battery pack 10, and the main circuit is formed by connecting the output positive pole, the battery pack positive pole, the battery pack negative pole and the output negative pole. loop.

Specifically, when the main circuit is working normally, the voltage dividing resistor 111b is connected in parallel to the two ends of the battery pack 10, that is, respectively connected to the battery pack positive pole and the battery pack negative pole of the battery pack 10, and the voltage on the voltage dividing resistor 111b is the same as The voltages at both ends of the battery pack 10 are equal, and the two different pins in the power metering chip 113 are respectively connected to the two ends of the voltage dividing resistor 111b to obtain the sampling voltage collected by the voltage dividing resistor 111b, wherein the sampling voltage is the voltage of the battery pack. 10 The ratio of the voltage at both ends to the number of batteries in the battery pack 10, that is, the average voltage of each battery in the battery pack 10; the current detection resistor 111a is connected in series in the main circuit, if one end of the current detection resistor 111a is connected to the positive pole of the battery pack, then The other end is connected to the positive pole of the output. If one end of the current detection resistor 111a is connected to the negative pole of the battery pack, the other end is connected to the negative pole of the output. Two different pins of the fuel gauge chip 113 are respectively connected to both ends of the current detection resistor 111a to obtain the sampling current collected by the current detection resistor 111a.

Further, the microprocessor 12 is specifically used for:

If the battery power is greater than the preset first power threshold and less than the preset second power threshold, the generated main circuit switch closing signal is determined as the first control signal;

If the battery power is greater than the preset second power threshold and less than the preset third power threshold, the generated pre-discharge signal is determined as the first control signal;

If the battery power is greater than the preset third power threshold, the generated main loop switch disconnection signal is determined as the first control signal.

In this embodiment, the pre-charging signal can be understood as a control signal used to control the battery pack 10 to pre-charge; the main circuit switch closing signal can be understood as a control signal used to control the main circuit switch to be closed, so that the battery pack 10 can be charged and discharged normally. The control signal; the pre-discharge signal can be understood as a control signal for controlling the battery pack 10 to perform pre-discharge; the main circuit switch disconnection signal can be understood as a signal for controlling the main circuit switch to be disconnected so that the battery pack 10 stops charging and discharging control signal.

In this embodiment, the preset first power threshold, the preset second power threshold and the preset third power threshold can be understood as preset power values corresponding to the control signals for controlling the battery pack .

Specifically, if the battery power is less than the preset first power threshold, it can be considered that the current battery pack power is low. Since the battery pack has a relatively high energy ratio, in order to avoid damage to the battery in the battery pack 10, affect the service life or bring potential safety hazard, the microprocessor 12 can generate a first control signal whose content is a pre-charging signal, so that the battery pack 10 enters a pre-charging state; if the battery power is greater than or equal to the preset first power threshold and less than the preset second power threshold, It can be considered that the current battery pack can work directly. At this time, the microprocessor 12 can generate the first control signal with the content of the main loop switch closing signal, so that the battery pack 10 can work normally; if the battery power is greater than or equal to the preset second power Threshold and less than the preset first power threshold, it can be considered that the power in the current battery pack is too high, which is not conducive to battery stability and storage, but it has not reached the level that needs to stop working immediately, and the microprocessor 12 can generate the content as a pre-discharge signal The first control signal, so that the battery pack 10 enters the pre-discharge state, so as to reduce the power of the battery pack 10 and reduce potential safety hazards without affecting the normal operation of the circuit; if the battery power is greater than or equal to the preset third power threshold, it can be considered The power in the current battery pack is too high, which has affected the safety of the circuit work, and the circuit cannot be continued to be connected to work. The microprocessor 12 can generate the first control signal of the main circuit switch disconnection signal, so that the circuit is disconnected, and the battery pack 10 stop working.

Embodiment two

Fig. 4 is a schematic structural diagram of a battery management system provided by Embodiment 2 of the present invention. The technical solution of this embodiment is further refined on the basis of the above-mentioned technical solutions. The battery management system also includes an analog front-end device 13, a battery pack equalizer circuit 14 , reset chip 15 , main circuit switch 16 and pre-charge and discharge module 17 .

The analog front-end device 13 is connected with the battery pack 10 and the microprocessor 12 respectively, and is used to detect the voltage and current of each battery 101 in the battery pack 10 and the highest temperature in the battery pack 10, and generate The second control signal is used for battery management, and transmits each voltage, each current and the highest temperature to the microprocessor 12 .

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

The battery pack equalization circuit 14 is connected to the analog front-end device 13, and is respectively connected to each battery 101 in the battery pack 10, and is used to control each The battery 101 performs voltage equalization.

The reset chip 15 is connected to the reset pin of the microprocessor 12, and is used to send a reset signal to the reset pin when detecting a failure 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 connected with the microprocessor 12 and the analog front-end device 13 respectively, and is used to close when receiving the main circuit switch closing signal, so that the main circuit is connected, and when receiving the main circuit switch Open when the signal is disconnected, so that the main circuit is disconnected.

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

Wherein, the main circuit switch closing signal, the main circuit switch opening signal, the pre-charging signal and the pre-discharging signal are the first control signal and the third control signal from the microprocessor 12, and the first control signal from the analog front-end device 13 Two control signals.

Specifically, the analog front-end device 13 is respectively connected to each battery 101 in the battery pack 10 through wires, and is used to detect the voltage and current corresponding to each battery 101 in the battery pack 10 through the resistance sampling method, as well as the maximum temperature in the battery pack 10, according to Each voltage, each current and the highest temperature determine the operating state of the circuit and the battery pack 10, 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 also connected to the input port of the microprocessor 12 It is used to transmit the acquired voltages, currents and maximum temperature to the microprocessor 12 through wire connection. Correspondingly, the microprocessor 12 can generate a third control signal for battery management according to the received voltages, currents and maximum temperature, and according to preset control conditions therein.

Specifically, the battery pack balancing circuit 14 is respectively connected to each battery 101 in the battery pack 10 and the analog front-end device 13 through different IO ports, for receiving the second control signal sent by the analog front-end device 13, and the second When the control signal is an equalization start signal, the voltage of each connected battery 101 is equalized, so that the battery pack 10 can solve the problem of voltage inconsistency caused by high current flying of each battery 101 when the battery pack 10 is not working. Optionally, the battery pack equalization circuit 14 may be a set of equalization circuits and voltage acquisition circuits, which is not limited in this embodiment of the present invention.

Specifically, reset chip 15 can be a reset IC chip, is connected with the reset pin of microprocessor 12 through IO port, when detecting that microprocessor 12 breaks down, reset chip 15 sends reset signal to reset pin, so that The reset pin is at a low level to reset the microprocessor 12 . By resetting the chip 15, the failure of the microprocessor 12 to crash due to the high and low rotation of the unmanned aerial vehicle when the battery pack 10 is used in the unmanned aerial vehicle can be better solved.

Specifically, the main circuit switch 16 is directly connected in series with the main circuit, one end is connected to the positive pole or the negative pole of the battery pack 10, and one end is connected to the output positive pole or the output negative pole, and the input port of the main circuit switch 16 is connected to the microprocessor 12 and the analog front-end device respectively. The output port of 13 is connected by a wire, and is used to receive the first control signal, the second control signal or the third control signal sent by the microprocessor 12 and the analog front-end device 13, when the received control signal is the closing signal of the main loop switch , the main circuit switch 16 is closed to connect the main circuit, and when the received control signal is the main circuit switch disconnection 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 circuit, one end is connected to the positive pole or negative pole of the battery pack 10, the other end is connected to the output positive pole or the output negative pole, and is connected in parallel with the main circuit switch 16. The input of the pre-charging and discharging module 17 The ports are also respectively connected to the output ports of the microprocessor 12 and the analog front-end device 13 by wires, and are used to receive the first control signal, the second control signal or the third control signal sent by the microprocessor 12 and the analog front-end device 13, when When the received control signal is a pre-charge signal, the pre-charge and discharge module 17 controls the pre-charge switch to be closed to pre-charge the battery pack 10; when the received control signal is a pre-discharge signal, the pre-charge and discharge module 17 controls the pre-discharge The switch is closed, and the battery pack 10 is pre-discharged.

It needs to be clear that the power communication output shown in Figure 4 is the content output between the output positive pole and the output negative pole. Any module in the charging and discharging module 17 is provided.

Further, FIG. 5 is a schematic structural diagram of an analog front-end device provided by Embodiment 2 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 set at the theoretical maximum temperature in the battery pack 10, and the output terminal of the second temperature sensor 131 is connected to the pin of the analog front-end chip 132 for collecting the highest temperature in the battery pack 10. temperature, and send the highest temperature to the analog front-end chip 132 .

In this 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 used to obtain the maximum temperature according to the received maximum temperature. The voltage and current of each battery 101 in the battery pack 10 generates a second control signal for battery management, and transmits each voltage, each current and the highest temperature to the microprocessor 12 .

Specifically, the second temperature sensor 131 is set at the 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 As the warning temperature of the battery pack 10, the output end of the second temperature sensor 131 is connected with the pin of the analog front-end chip 132, and the highest temperature can be sent to the analog front-end chip 132 through this connection; Connect with the positive terminal of each battery 101 in the second temperature sensor 131, the microprocessor 12 and the battery pack 10, obtain the corresponding voltage and current of each battery by the connection with each battery 101 with the resistance sampling method, pass through the connection with the second temperature sensor The connection of 131 directly obtains the highest temperature collected by the second temperature sensor 131, and generates the second control signal for battery management according to each voltage, each current, the highest temperature and the circuit protection evaluation standard preset in the analog front-end chip 132 ; The output pin of the analog front-end chip 132 is connected to the input port of the microprocessor 12 through wires, and is used to transfer the acquired voltages, currents and maximum temperature to the microprocessor 12 .

Further, the analog front-end chip 132 is specifically used for:

Specifically, if each current is less than the preset first current threshold and the highest temperature is lower than the preset first temperature threshold, it can be considered that some batteries in the current battery pack 10 have low power and are within the safe operating temperature range, and the analog front-end chip 132 can Generate a second control signal whose content is a pre-charge signal, so that the battery pack 10 enters a pre-charge state; 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 A temperature threshold, it can be considered that the current battery capacity can support normal operation and is within the safe operating temperature range. At this time, the analog front-end chip 132 can generate a second control signal with the content of the main circuit switch closing signal, so that the battery pack 10 is normal. Work; 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 lower than the preset first temperature threshold, it can be considered that the power of some batteries in the current battery pack 10 is too high, It may affect the safety of the circuit work, but it has not yet reached the level of needing to stop working immediately, and the temperature of the current battery pack 10 is within the safe operating temperature range. At this time, the analog front-end chip 132 can generate a second signal whose content is a pre-discharge signal. control signal, so that the battery pack 10 enters the pre-discharge state, so as to reduce the power of the battery pack 10 and reduce potential safety hazards without affecting the normal operation of the circuit; 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 battery pack 10 is too large, there is a possibility of overcurrent or short circuit fault, or the temperature of the current battery pack 10 has exceeded the safe operating temperature range , has affected the safety of the loop operation, and the loop cannot be continued to be connected to work. At this time, the analog front-end chip 132 can generate a second control signal with the content of the main loop switch disconnection signal, so that the loop is disconnected, and the battery pack 10 stops working; if If the voltage difference between any two batteries 101 in the battery pack 10 is greater than the preset voltage difference, it can be considered that the voltages of the batteries 101 in the battery pack 10 are unbalanced. At this time, the analog front-end chip 132 can generate a second signal whose content is a balanced start signal. control signal, and send the second control signal to the battery pack balancing circuit 14 through the corresponding pin, so that the battery pack balancing circuit 14 performs voltage balancing on each battery 101 in the battery pack 10 .

Correspondingly, the microprocessor 12 is also used for:

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, the generated main circuit switch disconnection signal is determined as the first Three control signals;

Specifically, if each voltage is lower than the preset first voltage threshold, each current is lower than the preset fourth current threshold, and the highest temperature is lower than the preset second temperature threshold, it can be considered that some batteries in the current battery pack 10 have low power and Within the safe operating temperature range, the microprocessor 12 can generate a third control signal whose content is a pre-charging signal, so that the battery pack 10 enters the charging state; if each voltage is greater than or equal to the preset first voltage threshold and less than Preset the 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, it can be considered that each battery 101 in the current battery pack 10 Both the voltage and current can support the normal operation of the circuit, and the temperature of the entire battery pack 10 is within the safe operating temperature range. At this time, the microprocessor 12 can generate a third control signal with the content of the main circuit switch closing signal, so that the battery pack 10 is normal. Work; 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 Presetting the second temperature threshold, it can be considered that the power of some batteries in the current battery pack 10 is too high, or the voltage and current of some batteries are too high, which may affect the safety of the circuit operation, but it has not yet reached the level where the work needs to be stopped immediately. And the current 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 the pre-discharge state, so as not to affect the normal operation of the circuit. In this case, reduce the power of the high-voltage, high-current battery 101 in the battery pack 10 to 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 If the 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 battery pack 10 is too large, there is a possibility of overcurrent or short circuit fault, or the temperature of the current battery pack 10 has exceeded the safe working temperature. The temperature range has affected the safety of the loop, and the loop cannot be continued to work. At this time, the microprocessor 12 can generate a third control signal with the content of the disconnection signal of the main loop switch, 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 The threshold is less than the preset first temperature threshold, indicating that the condition for the microprocessor 12 to generate the same control signal 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, while the microprocessor 12 is based on actual needs. Control signal generation is performed to realize flexible management of charging and discharging of the battery pack.

Exemplarily, FIG. 6 is a schematic circuit diagram of a battery management system provided in Embodiment 2 of the present invention. The circuit shown in FIG. Some components are omitted, and the pin sequence is not exactly the same as the actual device. Among them, BAT+, BAT-, PACK+, PACK-, RX/TX are the positive pole of the battery pack, the negative pole of the battery pack, the positive pole of the output, the negative pole of the output and the communication port; Q1 and Q2 are the main circuit switches for battery management N MOS, Q3 and Q4 are the P MOS switches in the pre-charge and discharge module used for battery management, which are used to control the pre-charge and pre-discharge of the battery pack; CELL1, CELL2... are the batteries connected in series in the battery pack.

Continuing from the above example, U1 is a power metering chip, which is used to calculate the battery power of the battery pack. This application uses the single-cell power metering chip BQ27Z561 as an example for illustration. U1 is connected to the battery pack through the first pin to receive power from the battery pack; R1 and R2 are the voltage dividing resistors of the battery pack, which are respectively connected to the third pin and the seventh pin of U1 to collect the voltage of the battery pack and calculate the battery pack as a whole; SENSE is connected in series to the main circuit The two ends of the current detection resistor in the battery pack are respectively connected to the fourth pin and the fifth pin of U1 to collect the current of each battery in the battery pack; RT1 is a temperature sensor set at the theoretical average temperature in the battery pack, It is connected with the fifth pin of U1 to transmit the collected average temperature of the battery pack to U1; the second pin of U1 is connected with the second pin of the microprocessor U2 to realize the communication between U1 and U2 communicate with each other.

Following the above example, U2 is a microprocessor, which is mainly used to generate control signals based on received battery voltage, current, power and temperature information to control battery functions and internal and external communications. Among them, the first pin of U2 is connected with the ninth pin of the analog front-end chip U3 to realize mutual communication with U3; the second pin of U2 is connected with the second pin of U1 to realize the communication between U1 and Mutual communication between U2; the third pin of U2 is connected to the input ports of devices such as Q1, Q2, Q3, and Q4 to transmit other logic control information to the corresponding device; the fourth pin of U2 is connected to the external communication port RX /TX connection for external communication; the fifth pin of U2 is the ground terminal; the sixth pin of U2 is connected to the battery pack to receive the power supply of the battery pack; the seventh pin of U2 is the reset pin, and The reset chip U4 is connected to receive the reset signal of U4 in case of failure.

Following the above example, U3 is an analog front-end chip, which is used to detect the voltage and current of each battery in the battery pack, realize the overcurrent and short circuit protection of the battery pack, and control the pre-charge and pre-discharge MOS switches according to preset conditions, etc. In this application, the BQ76952 chip is taken as an example for illustration. U3 is respectively connected to the input ports of Q1, Q2, Q3 and Q4 through the first pin, the second pin, the fourteenth pin and the thirteenth pin, so as to send the generated control signal to the corresponding device; The third pin, the fourth pin and the fifth pin of U3 are respectively connected to the sixth pin, the fifth pin and the fourth pin of the equalizing circuit U5 to receive voltage information of different batteries in the battery pack, And when needed, send the generated equalization open signal to U5 through the corresponding pin; the sixth pin and the seventh pin of U3 are respectively connected to the two ends of SENSE to collect the current of each battery in the battery pack; The eighth pin is the ground terminal; the ninth pin of U3 is connected to the first pin of U2 to realize mutual communication between U2 and U3; the tenth pin of U3 is connected to the battery pack to receive the battery pack power supply; the eleventh pin of U3 is connected to the sixth pin of U4 to realize mutual communication between U3 and U4; the twelfth pin of U3 is connected to the temperature sensor set at the theoretical maximum temperature in the battery pack RT2 connection to obtain the maximum temperature of the battery pack.

Continuing from the above example, U4 is a reset chip, which is used to reset U2 when the motor rotates up and down when the drone is flying, which causes the microprocessor U2 to crash. The first pin of U4 is connected to the seventh pin of U2 to send a reset signal to U2 when it fails; the second pin of U4 is used to receive the reset input signal of U2; the fifth pin of U4 is grounded terminal; the sixth pin of U4 is connected to the eleventh pin of U3 for mutual communication between U3 and U4.

Continuing from the above example, U5 is an equalization circuit, which is used to collect the voltage of each battery in the battery pack. At the same time, when the battery pack is not working, according to the received equalization open signal, it solves the problem of unmanned aerial vehicles flying with high current. The problem of the inconsistent voltage of each battery. Among them, the first pin, the second pin and the third pin of U5 are respectively connected to the positive electrodes of different batteries in the battery pack; the fourth pin, the fifth pin and the sixth pin of U5 are connected to the first pin of U3 respectively. The five pins, the fourth pin and the third pin are connected.

The battery management system provided in this embodiment, on the basis of the existing management method for a battery pack composed of multiple batteries, introduces a single-battery power metering chip, and combines the high-precision power metering algorithm of the single-cell power metering chip to manage the battery pack as a whole. Battery power calculation, so that the microprocessor can generate a higher-precision control signal according to the high-precision battery power, and introduce a reset chip, so that the microprocessor can reset and start in time when a fault occurs, and realize the high-precision control of the multi-battery battery pack. Accurate, high-safety management improves the flexibility of battery management and reduces the complexity of microprocessor information processing.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims

A battery management system, characterized in that it includes: a battery pack, a power meter and a microprocessor;

The power metering device is connected to the battery pack and the microprocessor respectively, and is used to detect the voltage, current and temperature information of the battery pack, determine the battery power of the battery pack, and calculate the battery power passed to said microprocessor;

The microprocessor is configured to generate a first control signal for battery management according to the battery level;

The battery pack includes at least two batteries connected in series, and is also connected to the microprocessor for supplying power to the electricity metering device and the microprocessor.
The system according to claim 1, wherein the power metering device comprises: a current and voltage sampling module, a first temperature sensor and a power metering chip;

The current and voltage sampling module is connected to the pins of the power metering chip, and is used to obtain the sampling voltage and sampling current of the battery pack, and send the sampling voltage and the sampling current to the power metering chip ;

The first temperature sensor is set at the theoretical average temperature in the battery pack, and the output terminal of the first temperature sensor is connected to the pin of the power metering chip for collecting the average temperature in the battery pack , and sending the average temperature to the power metering chip;

The electricity metering chip is connected to the current and voltage sampling module, the first temperature sensor and the microprocessor respectively through different pins, and is used for receiving the sampling voltage, the sampling current and the received determining the battery charge of the battery pack at the average temperature, and communicating the battery charge to the microprocessor;

Wherein, the power metering chip is a single battery power metering chip.
The system according to claim 2, wherein the current and voltage sampling module comprises:

current sense resistors and voltage divider resistors, where:

The voltage dividing resistor is connected in parallel to both ends of the battery pack for obtaining 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 resistor is directly connected in series with the main circuit, and is connected in series with one end of the battery pack to obtain the sampling current, the sampling current is the current flowing through the battery pack, and the main circuit is the output positive pole , The positive pole of the battery pack, the negative pole of the battery pack and the output negative pole are connected to form a loop.
The system according to claim 1, wherein the microprocessor is specifically used for:

If the battery power is less than a preset first power threshold, determining the generated pre-charge signal as the first control signal;

If the battery power is greater than or equal to the preset first power threshold and less than the preset second power threshold, the generated main circuit switch closing signal is determined as the first control signal;

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

If the battery power is greater than or equal to the preset third power threshold, the generated main loop switch disconnection signal is determined as the first control signal.
The system according to claim 1, further comprising: an analog front-end device;

The analog front-end device is connected to the battery pack and the microprocessor respectively, and is used to detect the voltage and current of each battery in the battery pack and the highest temperature in the battery pack, and according to each of the voltages, generating a second control signal for battery management for each of the currents and the maximum temperature, and communicating each of the voltages, each of the currents and the maximum temperature to the microprocessor;

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 highest temperatures.
The system according to claim 5, wherein the analog front-end device comprises: a second temperature sensor and an analog front-end chip;

The second temperature sensor is set at the theoretical maximum temperature in the battery pack, and the output terminal of the second temperature sensor is connected to the pin of the analog front-end chip 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 to the second temperature sensor, the microprocessor, and the positive terminals of the batteries in the battery pack through different pins, and is used to receive the highest temperature according to the received maximum temperature and the acquired The voltage and current of each battery in the battery pack generate a second control signal for battery management, and transmit each of the voltages, each of the currents and the maximum temperature to the microprocessor.
The system according to claim 6, wherein the analog front-end chip is specifically used for:

If each of the currents is less than a preset first current threshold and the highest temperature is less than a preset first temperature threshold, determining the generated pre-charge signal as the second control signal;

If each of the currents is greater than or equal to the preset first current threshold and less than the preset second current threshold, and the highest temperature is lower than the preset first temperature threshold, determine the generated main loop switch closing signal is the second control signal;

If each of the currents is greater than or equal to the preset second current threshold and less than the preset third current threshold, and the highest temperature is lower than the preset first temperature threshold, determine the generated pre-discharge signal as the preset the second control signal;

If any of the currents 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, the generated main loop switch disconnection signal is determined as the second control signal;

If the difference between any two voltages is greater than the preset voltage difference, the generated equalization enable signal is determined as the second control signal.
The system according to claim 7, wherein the microprocessor is also used for:

If each of the voltages is less than a preset first voltage threshold, each of the currents is less than a preset fourth current threshold, and the highest temperature is less than a preset second temperature threshold, the generated pre-charge signal is determined as the third control signal;

If each of the voltages is greater than or equal to the preset first voltage threshold and less than the preset second voltage threshold, each of the currents 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 a preset second temperature threshold, determining the generated main loop switch closure signal as the third control signal;

If each of the voltages is greater than or equal to the preset second voltage threshold and less than the preset third voltage threshold, each of the currents 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 a preset second temperature threshold, determining the generated pre-discharge signal as the third control signal;

If any of the voltages is greater than or equal to the preset third voltage threshold, any of the currents is greater than or equal to the preset sixth current threshold, or the highest temperature is greater than the preset second temperature threshold, a The main loop switch disconnection signal is determined as the third control signal;

Wherein, 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, and the preset sixth current threshold is smaller than the preset A third current threshold is set, and the preset second temperature threshold is smaller than the preset first temperature threshold.
The system according to claim 5, further comprising: a battery pack balancing circuit;

The battery pack equalization circuit is connected to the analog front-end device, and is respectively connected to each battery in the battery pack, for receiving the second control signal sent by the analog front-end device, which is an equalization start signal. When the signal is activated, voltage equalization is performed on each of the batteries.
The system according to claim 1, further comprising: a reset chip;

The reset chip is connected to the reset pin of the microprocessor, and is used to send a reset signal to the reset pin when a failure of the microprocessor is detected, so that the reset pin is at a low level, and the The microprocessor is reset.
The system according to any one of claims 1-10, further comprising: a main circuit switch and a pre-charging and discharging module;

The main circuit switch is directly connected in series with the main circuit, and is respectively connected with the microprocessor and the analog front-end device, and is used to close when receiving the closing signal of the main circuit switch, so that the main circuit is connected, and when receiving The main circuit switch is disconnected when the signal is disconnected, so that the main circuit is disconnected;

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

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