Active equalization channel control circuit and battery

Abstract

The invention discloses an active equalization channel control circuit and a battery, which are applied to the field of energy storage control, and two functions of sampling and execution control are integrated on an AFE module, so that the active equalization control circuit does not need an MCU to participate in the control process of a switch matrix module. The function of executing control on the switch matrix module can be completed on the same side of the isolation communication loop, signal isolation processing needed when an MCU is used for sending control signals to the switch matrix module is avoided, the working steps and processes of the active equalization control circuit are reduced, the circuit is simplified, energy consumption generated by isolation processing is avoided, and the service life of the active equalization control circuit is prolonged. And the reliability and the environmental protection property of the active equalization control circuit are improved. The control of the switch matrix module is executed by the AFE module, the following module and the AFE module can be expanded conveniently, in addition, the AFE module is high in cost, and the flexibility and reliability of the active equalization control circuit are greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of energy storage control, and in particular to an active balancing channel control circuit and a battery. Background Art

[0002] The current energy storage system is developing towards a direction of increasing cell capacity. The currently widely used passive balancing solution can no longer meet the balancing needs, and the application of active balancing will become more and more common. For cost considerations, an active balancing loop is usually set in one or several modules, and the selection of different balancing cells is achieved by switching the switch matrix. The current switching solutions of several switch matrices can be found in the prior art section.

[0003] like Figure 1 As shown, the prior art uses EMB1428 to switch the switch matrix, which needs to be used with EMB1499. The usage is inflexible, the circuit connection is relatively complex, the overall circuit cost is high, and the reliability is low. In addition, it only supports a 12-channel switch matrix, which is not easy to expand the battery module.

[0004] It can be seen that there is an urgent need for an active balancing control circuit with high reliability that can easily control the switch matrix, is easy to expand the battery module, and has lower cost and energy consumption. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide an active balancing channel control circuit and a battery, which solves the problems of complex connection, high circuit cost, low reliability and difficulty in expansion of the active balancing channel control circuit. The specific scheme is as follows:

[0006] In a first aspect, the present application provides an active equalization channel control circuit, including: an equalization loop and an MCU, and also including: an AFE module, a switch matrix module and a drive loop;

[0007] The cell sampling input channel of the AFE module is connected to the battery module to collect the data signal of the battery module;

[0008] The information transmission channel of the AFE module is connected to the MCU, and is used to transmit the collected data signal and obtain a first control signal output by the MCU after processing the data signal;

[0009] The passive equalization control output channel of the AFE module is connected to the driving circuit, and is used to send a second control signal to the driving circuit based on the first control signal;

[0010] The output end of the driving circuit is connected to the switch matrix module, and is used to send a third control signal to the switch matrix module based on the second control signal;

[0011] The switch matrix module is disposed between the balancing circuit and the battery module, and is used to control the battery module to charge and discharge to the balancing circuit based on the third control signal.

[0012] Optionally, the AFE module includes multiple groups of acquisition units, the battery module includes multiple groups of battery cells, one group of acquisition units corresponds to one battery cell, and the acquisition unit includes a first switch tube and a second switch tube;

[0013] The first end of the battery unit is connected to the first end of the first switch tube;

[0014] The second end of the battery unit is connected to the second end of the second switch tube;

[0015] The second end of the first switch tube is connected to the first end of the second switch tube.

[0016] Optionally, the acquisition unit further includes: a temperature sensor;

[0017] The input end of the temperature sensor is arranged between the battery cells connected in series.

[0018] Optionally, the driving circuit includes a plurality of control units, and the control unit includes: a third switch tube;

[0019] The first end of the third switch tube is connected to the first end of the corresponding battery cell in the battery module;

[0020] The first end of the third switch tube is used as the output end of the control unit, and is used to send a third control signal to the corresponding switch matrix unit in the switch matrix module;

[0021] The control end of the third switch tube is connected to the second end of the first switch tube and the first end of the second switch tube.

[0022] Optionally, the driving circuit further includes: a driving chip;

[0023] The power supply terminal of the driving chip is connected to the stable voltage terminal of the AFE module;

[0024] The input terminal of the driving chip is connected to the driving enable signal terminal of the AFE module;

[0025] The high-side output terminal of the driving chip is connected to the first receiving terminal of the corresponding switch matrix unit in the switch matrix module;

[0026] The driving chip output terminal of the driving chip is connected to the second receiving terminal of the corresponding switch matrix unit in the switch matrix module.

[0027] Optionally, the switch matrix unit in the switch matrix module includes: a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, a first resistor, a second resistor and a third resistor;

[0028] The first end of the fourth switch tube is connected to the negative electrode of the balancing loop;

[0029] The second end of the fifth switch tube is connected to the second end of the battery unit;

[0030] The second end of the fourth switch tube is connected to the second end of the first resistor and the first end of the fifth switch tube;

[0031] The control end of the fourth switch tube, the control end of the fifth switch tube, the control end of the sixth switch tube, the control end of the seventh switch tube, the first end of the first resistor, the second end of the third resistor and the first end of the second resistor are connected;

[0032] The second end of the sixth switch tube is connected to the first end of the third resistor and the first end of the seventh switch tube;

[0033] The second end of the seventh switch tube is connected to the first end of the battery unit;

[0034] The first end of the sixth switch tube is connected to the positive electrode of the balancing loop.

[0035] Optionally, the switch tubes in the switch matrix module are all NMOS tubes.

[0036] Optionally, the highest node and the second highest node unit of the switch matrix unit are output by the AFE module through the driver chip of the drive circuit to realize balanced matrix switch control; the remaining switch matrix units are output by the AFE module through the control unit of the drive circuit to realize balanced matrix switch control, including:

[0037] The Nth acquisition unit of the AFE module is connected to the Nth battery cell of the battery module, and is used to acquire the data signal of the Nth battery cell of the battery module;

[0038] The N+2th passive balancing control output channel of the AFE module is connected to the Nth control unit of the drive circuit, and is used to send a second control signal to the Nth control unit of the drive circuit based on the collected data signal of the Nth battery cell of the battery module;

[0039] The Nth control unit of the driving circuit is connected to the Nth switch matrix unit of the switch matrix module, and is used to send a third control signal to the switch matrix module based on the second control signal;

[0040] The Nth switch matrix unit of the switch matrix module is connected to the Nth battery unit of the battery module, and is used to control the Nth battery unit of the battery module to charge and discharge to the balancing loop.

[0041] Optionally, the AFE modules are connected via a daisy chain, and the AFE module and the MCU are connected via a communication bridge chip.

[0042] In a second aspect, the present application provides a battery, comprising the above-mentioned active balancing channel control circuit.

[0043] It can be seen that in this application, by integrating the two functions of sampling and execution control on the AFE module, the active balancing control circuit does not need the MCU to participate in the control process of the switch matrix module, and the function of executing the control of the switch matrix module can be completed on the same side of the isolated communication loop, thereby avoiding the signal isolation processing required when using the MCU to send control signals to the switch matrix module, and thus reducing the working steps of the active balancing control circuit, simplifying the circuit, avoiding the energy consumption caused by the isolation processing, and improving the reliability and environmental protection of the active balancing control circuit. In addition, due to the high cost performance of the AFE module, when the system needs to expand the battery cells, compared with transmitting the added battery cell signals to the only MCU, the present application only needs to increase the number of AFE modules corresponding to the number of battery cells to complete the expansion, which greatly improves the flexibility and reliability of the active balancing control circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0045] Figure 1 An EMB1428+EMB1499 active equalization circuit diagram provided for related technologies;

[0046] Figure 2 A block diagram of an active balanced channel control system provided in an embodiment of the present application;

[0047] Figure 3 A block diagram of an ADBMS1818 application circuit provided in an embodiment of the present application;

[0048] Figure 4 An active equalization channel control circuit diagram provided in an embodiment of the present application;

[0049] Figure 5An active equalization channel control circuit diagram provided in an embodiment of the present application;

[0050] Figure 6 An active equalization channel control circuit diagram provided in an embodiment of the present application;

[0051] Figure 7 An active equalization channel control circuit diagram provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] The core of this application is to provide an active balanced channel control circuit.

[0054] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0055] The current energy storage system is developing towards a direction of increasing cell capacity. The currently widely used passive balancing solution can no longer meet the balancing needs, and the application of active balancing will become more and more common. For cost considerations, an active balancing loop is usually set in one or several modules, and the selection of different balancing cells is achieved by switching the switch matrix. The current switching solutions of several switch matrices can be found in the prior art section.

[0056] like Figure 1 As shown, the prior art performs switch matrix switching through EMB1428. The EMB1499 chip usually works in conjunction with the EMB1428 chip, and it is mainly responsible for some key links in the energy conversion process. Figure 1The switch matrix is ​​connected to the 7-cell Half-Stack structure composed of 7 battery cells on the left. The specific control process is: the EMB1428 chip first monitors the voltage and status of the battery cell through its pins connected to the battery cell. When a voltage difference is detected between the battery cells, the MCU or CPU sends a control decision to the EMB1428 chip according to the preset balancing strategy to determine which battery cells need energy balancing. The EMB1428 chip that receives the control decision switches the switch matrix by controlling the "SOURCE" and "GATE" pins so that the high-voltage battery cell can transfer energy to the low-voltage battery cell through the power switch controlled by the EMB1499 chip. This process needs to be used with the EMB1499, which is inflexible, the circuit connection is complex, and the reliability is low. And it only supports a 12-channel switch matrix, which is not easy to expand the battery module.

[0057] It can be seen that there is an urgent need for an active balancing control circuit with high reliability that can easily control the switch matrix, is easy to expand the battery module, and has lower cost and energy consumption.

[0058] See also Figure 2 As shown, in order to solve the above problems, this embodiment discloses an active equalization channel control circuit, including: an equalization loop and an MCU, and also including: an AFE module, a switch matrix module and a drive loop;

[0059] The cell sampling input channel of the AFE module is connected to the battery module to collect the data signal of the battery module;

[0060] The information transmission channel of the AFE module is connected to the MCU, and is used to transmit the collected data signal and obtain the first control signal output by the MCU after processing the data signal;

[0061] The passive equalization control output channel of the AFE module is connected to the driving circuit, and is used to send a second control signal Sn to the driving circuit based on the first control signal;

[0062] The output end of the driving loop is connected to the switch matrix module, and is used to send a third control signal SWn-2 to the switch matrix module based on the second control signal Sn;

[0063] The switch matrix module is disposed between the balancing loop and the battery module, and is used to control the battery module to charge and discharge the balancing loop based on the third control signal SWn.

[0064] like Figure 2As shown, the cell sampling input channel of the AFE module is connected to the battery module, and is used to collect the voltage signal of each battery cell in the battery module and the temperature signal of the branch where it is located, monitor the voltage and temperature status of each battery cell in real time, and transmit the voltage signal and temperature signal to the MCU through the information transmission channel, so that the MCU can evaluate the status of the battery cells in the battery module, calculate the capacity difference of different battery cells, and calculate the balancing channel, balancing method and balancing time according to the capacity difference of different battery cells, and generate a corresponding first control signal and transmit it to the AFE module. The AFE module converts based on the first control signal, thereby generating a second control signal Sn and transmitting it to the drive circuit through the passive balancing control output channel. The drive circuit is directly connected to the switch matrix module. The drive circuit transmits the third control signal SWn-2 to the switch matrix module based on the second control signal Sn to control the on and off of the switch matrix module. From the entire logic flow, it can be seen that the entire control process is carried out by the AFE module to exchange information with the MCU through the isolated communication loop. After receiving the balancing instruction, the AFE executes the opening and closing actions of the balancing loop. Compared with the existing technology where the MCU directly drives the switch matrix, there is no need to isolate the driving signal, and at the same time, the resource requirements of the MCU's IO port are reduced. At the same time, Figure 2 As shown, the SWn_EN and SWn-1_EN signals transmitted by the AFE module are used to control the third control signals SWn and SWn-1 of the highest section and the second highest section equalization channel output by the drive circuit. The implementation method is as follows Figure 5 The switch matrix module is directly connected to the battery module, wherein the switch matrix units in the switch matrix module correspond one-to-one to the battery units in the battery module.

[0065] The AFE module has a signal acquisition unit. In a specific implementation, it mainly collects the battery voltage and realizes the passive balancing function of the battery cell. Figure 3 Taking the ADBMS1818 chip as an example, in the system application circuit, pins C0~C18 are the cell voltage sampling input channels, pins S1~S18 are the passive balancing control output channels, and each battery unit is connected to two cell voltage sampling input channels and one passive balancing control output channel. The IPB, IMB, IPA, and IMA in the chip are information transmission channels for information interaction with the MCU.

[0066] It can be understood that the switch matrix module control in this embodiment is performed by the AFE module. Figure 2 The AFE modules and the balancing circuits correspond one to one. When the system needs to expand the battery units, this embodiment only needs to increase the number of AFE modules and the corresponding balancing circuits corresponding to the number of battery units to complete the expansion.

[0067] It can be seen that in the embodiment of the present application, by integrating the two functions of sampling and execution control on the AFE module, the active balancing control circuit does not need the MCU to directly control the switch matrix module, and the function of executing the control of the switch matrix module can be completed on the same side of the isolated communication loop, thereby avoiding the signal isolation processing required when using the MCU to send control signals to the switch matrix module, and thus reducing the working steps of the active balancing control circuit, simplifying the circuit, avoiding the energy consumption caused by the isolation processing, and improving the reliability and environmental protection of the active balancing control circuit. In addition, due to the high cost performance of the AFE module, when the system needs to expand the battery cells, compared with transmitting the added battery cell signals to the only MCU, the present application only needs to increase the number of AFE modules corresponding to the number of battery cells to complete the expansion, which greatly improves the flexibility and reliability of the active balancing control circuit.

[0068] According to the above embodiments, this embodiment provides a specific solution and further describes the control process. When the AFE module transmits the control signal to the energy storage unit in the corresponding energy storage module, there are different control methods.

[0069] In a specific embodiment, the AFE module includes multiple groups of acquisition units, the battery module includes multiple groups of battery cells, one group of acquisition units corresponds to one battery cell, the acquisition unit includes a first switch tube and a second switch tube; the first end of the battery cell is connected to the first end of the first switch tube; the second end of the battery cell is connected to the second end of the second switch tube; the second end of the first switch tube is connected to the first end of the second switch tube.

[0070] like Figure 4 As shown, the left box is an internal diagram of the acquisition unit in the AFE module. When the AFE module receives the first control signal indicating that the battery cell CELLn needs to be actively balanced, the second switch tube Q2 is turned on. Since the first switch tube Q1 is a PMOS tube and the second switch tube Q2 is an NMOS tube, the first switch tube Q1 remains in the off state. At this time, the potential of the second control signal Sn is equal to Cn-1, and the low potential is output. It should be noted that CELLn here refers to a non-highest or second-highest battery cell. According to the above embodiment, this embodiment also provides a specific solution, the drive circuit includes a plurality of control units, and the control unit includes: a third switch tube Q3; the first end of the third switch tube Q3 is connected to the first end of the corresponding battery cell in the battery module; the first end of the third switch tube Q3 is used as the output end of the control unit, and is used to send a third control signal SWn-2 to the corresponding switch matrix unit in the switch matrix module; the control end of the third switch tube Q3 is connected to the second end of the first switch tube Q1 and the first end of the second switch tube Q2.

[0071] When the second control signal Sn connected to the control end of the third switch tube Q3 is output, the third switch tube Q3 is turned on accordingly, and the output signal of the third control signal SWn-2 is equal to Cn. It can be seen that the acquisition unit of the AFE module includes the first switch tube Q1 and the second switch tube Q2, and the driving circuit includes the third switch tube Q3. By controlling the conduction of the switch tube, the first control signal is reasonably converted into the second control signal Sn, and then converted into the third control signal SWn-2 to be output to the switch matrix module.

[0072] In another specific embodiment, the driving circuit also includes: a driving chip; the power supply end of the driving chip is connected to the stable voltage end of the AFE module; the input end of the driving chip is connected to the driving enable signal end of the AFE module; the high-side output end of the driving chip is connected to the first receiving end of the corresponding switch matrix unit in the switch matrix module; the driving chip output end of the driving chip is connected to the second receiving end of the corresponding switch matrix unit in the switch matrix module.

[0073] The driver chip needs the AFE module to transmit SWn_EN and SWn-1_EN as the control signal for the driver module to drive the highest section and the second highest section equalization loop. When the AFE module transmits SWn_EN and SWn-1_EN to the driver chip in the driver module, the driver module starts working. Figure 5 As shown, taking the driver chip IRS25752LPBF as an example, for the battery cell CELLn, U2 is the high-side driver chip, VS is the output terminal of the driver chip, and is connected to the second receiving terminal of the switch matrix unit corresponding to the battery cell CELLn. VCC is the power supply voltage of the driver chip, and the LDO output power supply in the AFE module can be used. SWn_EN is the drive enable signal, which is controlled through the IO port of the AFE module. SWn is the balancing switch drive signal, which is led out from the high-side output terminal and connected to the first receiving terminal of the corresponding switch matrix unit in the switch matrix module. When the AFE module receives the first control signal representing the active balancing control battery cell CELLn, the AFE module sends the second control signal drive enable signal SWn_EN to the signal input terminal of the driver chip of the drive circuit. After being processed by the driver chip, the third control signal SWn is transmitted to the second receiving terminal of the corresponding switch matrix unit in the switch matrix module through the output terminal of the driver chip to control the on and off of the switch matrix unit.

[0074] It can be seen that in the embodiment of the present application, after receiving the first control signal, the AFE module converts the signal into the second control signal Sn or SWn_EN / SWn-1_EN and transmits it to the control loop. The control loop further transmits the third control signal SWn to the switch matrix module according to the second control signal Sn or SWn_EN / SWn-1_EN, thereby forming a control signal transmission. Transmitting control signals through switches has the advantages of simplicity and reliability, and driving through driver chips has the advantage of high flexibility. Both methods can also be performed simultaneously. For the same AFE chip, these two control methods can be used to control different battery cells at the same time.

[0075] According to the above embodiment, this embodiment provides a specific solution, the acquisition unit further includes: a temperature sensor;

[0076] The input terminal of the temperature sensor is arranged between the battery cells connected in series.

[0077] The battery generates heat during the charging and discharging process. If the heat cannot be dissipated in time, the high battery temperature may cause thermal runaway, resulting in serious safety accidents such as combustion and explosion. The temperature sensor can monitor the battery temperature in real time. When the temperature approaches or exceeds the set safety threshold, it will promptly notify the MCU to take measures, such as reducing the charging current, stopping charging and discharging, or starting the cooling system, to ensure that the battery operates within the safe temperature range. The temperature sensor can timely measure the temperature of the branch where the battery unit is located to prevent excessive current and branch temperature increase caused by battery short circuit.

[0078] like Figure 6 As shown, according to the above embodiment, this embodiment provides a specific solution, the switch matrix unit in the switch matrix module includes: a fourth switch tube Q4, a fifth switch tube Q5, a sixth switch tube Q6, a seventh switch tube Q7, a first resistor R1, a second resistor R2 and a third resistor R3;

[0079] A first end of the fourth switch tube Q4 is connected to the negative electrode of the balancing loop;

[0080] The second end of the fifth switch tube Q5 is connected to the second end of the battery unit;

[0081] The second end of the fourth switch tube Q4 is connected to the second end of the first resistor R1 and the first end of the fifth switch tube Q5;

[0082] The control end of the fourth switch tube Q4, the control end of the fifth switch tube Q5, the control end of the sixth switch tube Q6, the control end of the seventh switch tube Q7, the first end of the first resistor R1, the second end of the third resistor R3 and the first end of the second resistor R2 are connected;

[0083] The second end of the sixth switch tube Q6 is connected to the first end of the third resistor R3 and the first end of the seventh switch tube Q7;

[0084] The second end of the seventh switch tube Q7 is connected to the first end of the battery unit;

[0085] A first end of the sixth switch tube Q6 is connected to the positive electrode of the balancing loop.

[0086] like Figure 6 As shown, in a specific implementation, the switch matrix unit is connected to the battery unit and the balancing circuit respectively. When the first receiving end of the switch matrix unit receives the third control signal SWn, the electrical signal flows through the first resistor R1, the second resistor R2 and the third resistor R3 in the corresponding switch matrix unit and then is divided, so that the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6 and the seventh switch tube Q in the corresponding switch matrix unit are turned on, wherein the balancing path where the fourth switch tube Q4 and the fifth switch tube Q5 are located is connected to the negative electrode of the balancing loop, and the balancing path where the sixth switch tube Q6 and the seventh switch tube Q are located is connected to the positive electrode of the balancing loop.

[0087] In a specific implementation, the switch tubes in the switch matrix module are all NMOS tubes, and the highest node and the second highest node units of the switch matrix unit are output by the AFE module through the driver chip of the drive circuit to realize balanced matrix switch control; the remaining switch matrix units are output by the AFE module through the control unit of the drive circuit to realize balanced matrix switch control, so that the Nth acquisition unit of the AFE module is connected to the Nth battery unit of the battery module, so as to collect the data signal of the Nth battery unit of the battery module;

[0088] The N+2th passive balancing control output channel of the AFE module is connected to the Nth control unit of the driving circuit, and is used to send a second control signal Sn+2 to the Nth control unit of the driving circuit based on the collected data signal of the Nth battery cell of the battery module;

[0089] The Nth control unit of the driving loop is connected to the Nth switch matrix unit of the switch matrix module, and is used to send a third control signal SWn to the switch matrix module based on the second control signal Sn+2;

[0090] The Nth switch matrix unit of the switch matrix module is connected to the Nth battery unit of the battery module, and is used to control the Nth battery unit of the battery module to charge and discharge to the balancing loop.

[0091] It can be understood that the conduction condition of the NMOS tube requires that the positive voltage difference between the gate voltage and the source voltage is greater than the threshold voltage. In order to ensure that the requirements for the MOS tube turn-on voltage are met, except for the highest and second highest cells, the switch matrix unit of the balancing circuit of the nth cell CELLn is controlled by the third control signal SWn output by the control unit of the drive circuit. As in the above embodiment, the balancing circuit switches of the highest two cells CELLn and CELLn-1 can be controlled by the driver chip in the drive circuit.

[0092] In a specific embodiment, Figure 7 As shown, multiple Figure 6 The switch matrix unit is connected in series with the functional modules of the battery unit and the balancing circuit. Taking the control of the switch matrix unit of the CELL1 channel as an example, Figure 6 and Figure 7 Electronic components in the same position have the same functions and are controlled by the MCU. Figure 4 The AFE module in the middle makes S3 output a low level, corresponding to the third switch tube Q3 being turned on, and then Figure 7 The potential of SW1 is equal to that of C3, which is the sum of the voltage of CELL1, the voltage of CELL2 and the voltage of CELL3. The corresponding switch matrix unit in the figure is controlled by the resistor divider to conduct the switch tube, and then the charging and discharging of the balancing circuit is controlled to achieve balanced charging or discharging of the battery cells.

[0093] It can be seen that in the embodiment of the present application, by collecting the data signal of the Nth battery cell, the second control signal Sn+2 is sent to the Nth control unit of the drive circuit, so that the Nth control unit of the drive circuit is connected to the Nth switch matrix unit of the switch matrix module, and the third control signal SWn can be sent to the switch matrix module based on the second control signal Sn+2. The third control signal SWn is equal to the sum of the voltages of the N+2 battery cells and the battery cells with the following order names. The third control signal SWn is turned on by the switch tube in the switch matrix unit after the resistor voltage division in the switch matrix unit, thereby controlling the charging and discharging of the balancing circuit, and thus realizing the charging or discharging balance of the battery cells. The balancing circuit switches of up to 2 battery cells CELLn and CELLn-1 can be controlled by the driver chip in the drive circuit. In this way, each battery cell can achieve the purpose of charging and discharging, the circuit structure is simple, flexible and reliable, and the reliability of the active balancing channel control circuit is improved.

[0094] According to the above embodiments, this embodiment provides a specific solution, in which the AFE modules are connected through a daisy chain, and the AFE modules and the MCU are connected through a communication bridge chip.

[0095] It is known that the battery module is composed of several battery cells connected in series to form a complex battery array. Each AFE module corresponds to a fixed number of battery cells and is responsible for collecting key parameters such as voltage, current and temperature of the corresponding battery cells in real time. Due to the large scale of the battery module, the AFE modules are connected in a daisy chain to build an efficient communication link.

[0096] Taking one group of battery cells in series as an example, the first AFE module is adjacent to the monomer at the starting end of the battery pack. It accurately collects the voltage signal of the first battery cell, converts it into digital quantity with the help of the built-in ADC, and can simultaneously measure the temperature at the connection point. These data are packaged and wait for transmission. On the one hand, the second AFE module collects the corresponding battery cell information, and on the other hand, receives the data from the first AFE module through the daisy chain dedicated interface, integrates it and transmits it downstream until the last AFE module completes the data aggregation of the entire link. This daisy chain connection has significant advantages. It not only reduces the complexity of wiring, but also ensures that data flows in an orderly and fast manner between the AFE modules. Even if an AFE module fails temporarily, the remaining modules can still maintain partial data transmission, but just avoid the faulty node to maximize the system integrity.

[0097] It is understandable that after the data is gathered at the last AFE module, it needs to be efficiently transmitted to the MCU responsible for overall control. Due to the differences in electrical characteristics and communication protocols between the AFE module and the MCU, a special communication bridge chip is used as part of the isolated communication loop to establish a stable connection between the two. Figure 2 As shown in the figure, the communication bridge chip, as an isolated communication circuit, adapts the specific format data output by the AFE module, converts it into a signal form that the MCU can accurately identify and process, and then sends the parameter information of the battery module to the MCU via the high-speed SPI or UART bus. After receiving the data, the MCU quickly analyzes it based on the built-in complex algorithm to determine the charging status and health status of the battery. Once it detects that the temperature of a battery cell is abnormally high or the voltage deviation is too large, it immediately issues instructions to adjust the charging current, start the cooling fan and other corresponding measures to ensure that the battery pack is always in a safe and efficient operation state.

[0098] It can be seen that in this embodiment, the daisy chain between AFE modules greatly reduces the number of connecting wires compared to other complex network topologies, such as star connection or mesh connection. At the same time, the daisy chain connection has a certain fault tolerance. On the link, if an AFE module fails, as long as it is not the AFE module at the beginning of the chain, the remaining modules can still continue to communicate. The communication bridge chip can provide electrical isolation function to prevent interference signals such as high voltage and high current in the battery management system from affecting the normal operation of the MCU. At the same time, it can also ensure the quality of the data signal transmitted from the AFE module, improving the stability and security of the system.

[0099] Finally, this embodiment provides a battery, including the above-mentioned active balancing channel control circuit.

[0100] The above is a detailed introduction to an active balancing channel control circuit and a battery provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can refer to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can refer to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0101] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. An active equalization channel control circuit, comprising: The balancing circuit and MCU are characterized by further comprising: an AFE module, a switch matrix module and a driving circuit; The cell sampling input channel of the AFE module is connected to the battery module to collect the data signal of the battery module; The information transmission channel of the AFE module is connected to the MCU, and is used to transmit the collected data signal and obtain a first control signal output by the MCU after processing the data signal; The passive equalization control output channel of the AFE module is connected to the driving circuit, and is used to send a second control signal to the driving circuit based on the first control signal; The output end of the driving circuit is connected to the switch matrix module, and is used to send a third control signal to the switch matrix module based on the second control signal; The switch matrix module is disposed between the balancing circuit and the battery module, and is used to control the battery module to charge and discharge to the balancing circuit based on the third control signal.

2. The active equalization channel control circuit according to claim 1, characterized in that: The AFE module includes multiple groups of acquisition units, the battery module includes multiple groups of battery cells, one group of acquisition units corresponds to one battery cell, and the acquisition unit includes a first switch tube and a second switch tube; The first end of the battery unit is connected to the first end of the first switch tube; The second end of the battery unit is connected to the second end of the second switch tube; The second end of the first switch tube is connected to the first end of the second switch tube.

3. The active equalization channel control circuit according to claim 2, characterized in that: The acquisition unit also includes: a temperature sensor; The input end of the temperature sensor is arranged between the battery cells connected in series.

4. The active equalization channel control circuit according to claim 1, characterized in that: The driving circuit includes a plurality of control units, and the control unit includes: a third switch tube; The first end of the third switch tube is connected to the first end of the corresponding battery cell in the battery module; The first end of the third switch tube is used as the output end of the control unit, and is used to send a third control signal to the corresponding switch matrix unit in the switch matrix module; The control end of the third switch tube is connected to the second end of the first switch tube and the first end of the second switch tube.

5. The active equalization channel control circuit according to claim 4, characterized in that: The driving circuit further includes: a driving chip; The power supply terminal of the driving chip is connected to the stable voltage terminal of the AFE module; The input terminal of the driving chip is connected to the driving enable signal terminal of the AFE module; The high-side output terminal of the driving chip is connected to the first receiving terminal of the corresponding switch matrix unit in the switch matrix module; The driving chip output terminal of the driving chip is connected to the second receiving terminal of the corresponding switch matrix unit in the switch matrix module.

6. The active equalization channel control circuit according to claim 1, characterized in that: The switch matrix unit in the switch matrix module includes: a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, a first resistor, a second resistor and a third resistor; The first end of the fourth switch tube is connected to the negative electrode of the balancing loop; The second end of the fifth switch tube is connected to the second end of the battery unit; The second end of the fourth switch tube is connected to the second end of the first resistor and the first end of the fifth switch tube; The control end of the fourth switch tube, the control end of the fifth switch tube, the control end of the sixth switch tube, the control end of the seventh switch tube, the first end of the first resistor, the second end of the third resistor and the first end of the second resistor are connected; The second end of the sixth switch tube is connected to the first end of the third resistor and the first end of the seventh switch tube; The second end of the seventh switch tube is connected to the first end of the battery unit; The first end of the sixth switch tube is connected to the positive electrode of the balancing loop.

7. The active equalization channel control circuit according to claim 6, characterized in that: The switch tubes in the switch matrix module are all NMOS tubes.

8. The active equalization channel control circuit according to any one of claims 1 to 7, characterized in that: The highest node and the second highest node unit of the switch matrix unit are outputted by the AFE module through the driving chip of the driving circuit to realize balanced matrix switch control; The remaining switch matrix units, the AFE module outputs the third control signal after passing through the control unit of the drive circuit to implement balanced matrix switch control, including: The Nth acquisition unit of the AFE module is connected to the Nth battery cell of the battery module, and is used to acquire the data signal of the Nth battery cell of the battery module; The N+2th passive balancing control output channel of the AFE module is connected to the Nth control unit of the drive circuit, and is used to send a second control signal to the Nth control unit of the drive circuit based on the collected data signal of the Nth battery cell of the battery module; The Nth control unit of the driving circuit is connected to the Nth switch matrix unit of the switch matrix module, and is used to send a third control signal to the switch matrix module based on the second control signal; The Nth switch matrix unit of the switch matrix module is connected to the Nth battery unit of the battery module, and is used to control the Nth battery unit of the battery module to charge and discharge to the balancing loop.

9. The active equalization channel control circuit according to any one of claims 1 to 7, characterized in that: The AFE modules are connected via a daisy chain, and the AFE module and the MCU are connected via a communication bridge chip.

10. A battery, characterized in that: The active equalization channel control circuit comprises the active equalization channel control circuit as claimed in any one of claims 1 to 9.

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