Balancing management system for SOC balancing rapid detection and balancing control

Abstract

The utility model provides an equalization management system used for SOC equalization rapid detection and equalization control, comprising a lithium battery pack, a master control unit MCU and a slave control unit SCU, the master control unit MCU comprises a current acquisition module, a serial port communication module and a CAN1 communication module; the slave control unit SCU comprises a data acquisition control module, a CAN2 communication module and an equalization module, wherein the equalization module is divided into a driving module and an execution module. Setting a starting threshold value and a stopping threshold value, when the SOC of the battery meets the triggering condition of the starting threshold value, the execution module selects a module needing to be equalized for equalization, and when the SOC of the battery pack meets the triggering condition of the stopping threshold value, equalization is stopped, and charging equalization of the lithium battery pack is achieved. The utility model has the advantages that the equalization management system has good charging and discharging effects on the lithium battery pack, the overall performance of the battery pack is improved, and the time for SOC equalization detection and equalization control can be reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery equalization management systems, and more specifically to an equalization management system for rapid detection and equalization control of SOC (State of Charge) equalization. Background Technology

[0002] Since its invention thirty years ago, lithium batteries have been widely used due to their advantages such as high energy density, lightweight, environmental friendliness, and long battery life. They have gradually replaced traditional lead-acid batteries and become the preferred battery for electric vehicles, occupying a mainstream position in the field of low-speed electric vehicles.

[0003] However, in the field of electric vehicles, due to the relatively low nominal voltage of individual lithium battery cells, hundreds or even thousands of lithium batteries are needed to form a battery pack to meet the operating voltage requirements of the electric motor. However, performance differences inevitably exist between individual battery cells. During the charging and discharging process of the battery pack, to prevent overcharging or over-discharging of individual cells, the charging and discharging protection mechanism will stop the charging and discharging behavior of the battery pack when any individual cell in the battery pack reaches the charging cutoff voltage or discharging cutoff voltage. Therefore, it is evident that the inferior quality of individual battery cells determines the upper limit of the battery pack's capacity.

[0004] To keep individual battery cells at roughly the same capacity, a battery equalization management system is typically used to control the battery pack. Currently, most equalization control methods involve individually detecting and adjusting the state of charge (SOC) of each battery cell, which increases the battery equalization time. Summary of the Invention

[0005] The main objective of this invention is to provide a balance management system for rapid detection and control of SOC equalization, which can solve the problem of long battery equalization time.

[0006] The technical solution adopted in this utility model is: a balance management system for SOC equalization fast detection and equalization control, including a lithium battery pack. The equalization management system adopts a dual-layer management system architecture, including a master control unit MCU and a slave control unit SCU.

[0007] The master control unit (MCU) and multiple slave control units (SCUs) form a tree structure. The master control unit (MCU) is used to collect data from the slave control units (SCUs) and control the actions of the slave control units (SCUs).

[0008] Furthermore, the main control unit MCU includes a current acquisition module, a serial communication module, and a CAN1 communication module. The current acquisition module is used to acquire the current of the lithium battery pack. The main control unit MCU communicates with the host computer via the serial communication module. The main control unit MCU also interacts with the vehicle controller and the slave control unit SCU via the CAN1 communication module.

[0009] Furthermore, the slave control unit (SCU) includes a data acquisition and control module, a CAN2 communication module, and an equalization module. The equalization module is divided into a drive module and an execution module. The data acquisition and control module is used to acquire the voltage of each battery cell in the lithium battery pack and use the SOC parameters of each battery as the basis for equalization judgment. It sets a start threshold and a stop threshold. When the difference between the maximum and minimum SOC values ​​of each battery cell is greater than the start threshold, it outputs a start equalization charge and discharge control signal to the drive module. The drive module controls the execution module to perform the equalization function. The execution module sequentially selects the batteries that need to be charged and discharged for equalization until the difference between the maximum and minimum SOC values ​​of each battery cell is less than the stop threshold, thereby realizing the charge and discharge equalization of the lithium battery pack.

[0010] Furthermore, the slave control unit (SCU) and the master control unit (MCU) communicate via a CAN2 communication module.

[0011] Furthermore, the equalization module adopts a conventional discharge equalization circuit structure. The equalization control signal is issued by the control module in the slave control unit (SCU), processed by the digital isolation chip, and then transmitted to the drive module to drive the execution module to perform the equalization function. When a battery needs to be equalized, the corresponding equalization circuit will be turned on, and the individual cell will be discharged through a resistor. The battery monitoring device monitors the voltage of each battery in real time and feeds back the result to determine whether equalization is needed.

[0012] Furthermore, the main control unit MCU uses a Freescale S12XS series microcontroller.

[0013] Furthermore, the slave control unit (SCU) uses a Freescale S12XS series microcontroller.

[0014] Furthermore, the main control unit (MCU) includes a current acquisition module, which acquires the current of the lithium battery pack through a Hall current sensor.

[0015] Furthermore, the slave control unit (SCU) includes a data acquisition and control module, which uses a voltage acquisition chip to acquire the voltage information of each battery in the lithium battery pack.

[0016] Furthermore, the slave control unit (SCU) controls the balanced charging and discharging of each battery through a switching chip based on the balanced charging and discharging control signal.

[0017] Compared with existing technologies, the equalization management system of this invention for rapid SOC equalization detection and control has the following advantages: This equalization management system provides excellent charging and discharging performance for lithium battery packs, improving the overall performance of the battery pack, and especially reducing the time for SOC equalization detection and control. The equalization module of this invention adopts a conventional discharge equalization circuit structure. The equalization control signal is issued by the control module in the slave control unit (SCU), processed by a digital isolation chip, and then transmitted to the drive module to drive the execution module to perform the equalization function.

[0018] When a battery cell needs to be balanced, the corresponding balancing circuit will be activated, and the cell will be discharged through a resistor. The battery monitoring device will monitor the battery voltage in real time and provide feedback to determine whether balancing is necessary.

[0019] The equalization management system of this utility model adopts a two-layer management structure, which is not only flexible and easy to install, but also has a good charging and discharging effect on lithium battery packs, which can improve the overall performance of battery packs and reduce the time for SOC equalization detection and equalization control. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0021] Figure 1 This is a general block diagram of the balanced management system structure of this utility model. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0023] like Figure 1 As shown, a balance management system for rapid detection and control of SOC (System-on-Chips) equalization adopts a two-layer management system architecture, including a master control unit (MCU) and a slave control unit (SCU). The MCU includes a current acquisition module, a serial communication module, and a CAN1 communication module. The current acquisition module uses a Hall current sensor to acquire the lithium battery pack current. The MCU communicates with the host computer via the serial communication module and also interacts with the vehicle controller and the SCU via the CAN1 communication module.

[0024] The slave control unit (SCU) includes a data acquisition and control module, a CAN2 communication module, and an equalization module. The equalization module is divided into a drive module and an execution module. The data acquisition and control module mainly collects the voltage of individual cells in the lithium battery pack and uses the SOC parameters of each cell as the basis for equalization judgment. The slave control unit (SCU) and the master control unit (MCU) also communicate through the CAN2 communication module.

[0025] Furthermore, the slave control unit (SCU) includes a data acquisition and control module, a CAN2 communication module, and an equalization module. The equalization module is divided into a drive module and an execution module. The data acquisition and control module is used to acquire the voltage of each battery cell in the lithium battery pack and use the SOC parameters of each battery as the basis for equalization judgment. It sets a start threshold and a stop threshold. When the difference between the maximum and minimum SOC values ​​of each battery cell is greater than the start threshold, it outputs a start equalization charge and discharge control signal to the drive module. The drive module controls the execution module to perform the equalization function. The execution module sequentially selects the batteries that need to be charged and discharged for equalization until the difference between the maximum and minimum SOC values ​​of each battery cell is less than the stop threshold, thereby realizing the charge and discharge equalization of the lithium battery pack.

[0026] Furthermore, the equalization module adopts a conventional discharge equalization circuit structure. The equalization control signal is issued by the control module in the slave control unit (SCU). The digital isolation chip, such as ADuM140x, ADuM120x, iCoupler, ISO77x, ISO78xx, or ISO76xx series, processes the signal and transmits it to the drive module to drive the execution module to perform the equalization function. When a battery cell needs to be equalized, the corresponding equalization circuit will be turned on, and the cell will be discharged through a resistor. The battery monitoring device monitors the voltage of each battery cell in real time and feeds back the result to determine whether equalization is needed.

[0027] In this invention, preferably, the main control unit (MCU) uses a Freescale S12XS series microcontroller; the slave control unit (SCU) uses a Freescale S12XS series microcontroller; the main control unit (MCU) includes a current acquisition module that acquires the current of the lithium battery pack through a Hall current sensor; the slave control unit (SCU) includes a data acquisition and control module that acquires the voltage of the lithium battery pack through a voltage acquisition chip, such as LN709 or CS12237; the slave control unit (SCU) controls the balanced charging and discharging of each battery through a switching chip, such as CD4051, CD4067, AD7501, or AD7506 series, according to the balanced charging and discharging control signal.

[0028] The working principle and process of this utility model: The SOC of a battery is defined as the ratio of the remaining battery capacity to its fully charged state, and its expression is:

[0029]

[0030] In the formula, C represents the remaining power, D represents the power in the fully charged state, and SOC represents the state of charge.

[0031] Set startup threshold and stopping threshold ,have Let the maximum SOC of each battery be... Minimum value .

[0032] When there is The drive module outputs a start equalization charge / discharge control signal to the drive module, which then controls the execution module to perform the equalization function. The execution module sequentially selects the batteries that need to be charged and discharged for equalization until the equalization is achieved. The equalization control ends at a certain time, achieving equalization of the charging and discharging of the lithium battery pack.

Claims

1. A balance management system for rapid detection and control of SOC (State of Charge) equalization, comprising a lithium battery pack, characterized in that, The balanced management system adopts a two-layer management system architecture, including a master control unit (MCU) and a slave control unit (SCU). The master control unit (MCU) and multiple slave control units (SCUs) form a tree structure. The master control unit (MCU) is used to collect data from the slave control units (SCUs) and control the actions of the slave control units (SCUs).

2. The equalization management system for rapid detection and equalization control of SOC equalization according to claim 1, characterized in that: The main control unit (MCU) includes a current acquisition module, a serial communication module, and a CAN1 communication module. The current acquisition module is used to acquire the current of the lithium battery pack. The MCU communicates with the host computer via the serial communication module. The MCU also interacts with the vehicle controller and the slave control unit (SCU) via the CAN1 communication module.

3. A balance management system for rapid detection and control of SOC balance according to claim 1 or 2, characterized in that: The slave control unit (SCU) includes a data acquisition and control module, a CAN2 communication module, and an equalization module. The equalization module is divided into a drive module and an execution module. The data acquisition and control module is used to collect the voltage of each battery cell in the lithium battery pack and use the SOC parameters of each battery as the basis for equalization judgment. It sets a start threshold and a stop threshold, and makes the start threshold greater than the stop threshold. When the difference between the maximum and minimum SOC values ​​of each battery cell is greater than the start threshold, it outputs a start equalization charge and discharge control signal to the drive module. The drive module controls the execution module to perform the equalization function. The execution module sequentially selects the batteries that need to be charged and discharged for equalization until the difference between the maximum and minimum SOC values ​​of each battery cell is less than the stop threshold, at which point equalization stops, thus realizing the charge and discharge equalization of the lithium battery pack.

4. A balance management system for rapid detection and control of SOC equalization according to claim 3, characterized in that: The slave control unit (SCU) is also connected and communicates with the master control unit (MCU) via a CAN2 communication module.

5. A balance management system for rapid detection and control of SOC equalization according to claim 4, characterized in that: The equalization module adopts a conventional discharge equalization circuit structure. The equalization control signal is issued by the control module in the slave control unit (SCU). After being processed by the digital isolation chip, it is transmitted to the drive module to drive the execution module to perform the equalization function. When a battery needs to be equalized, the corresponding equalization circuit will be turned on, and the individual cell will be discharged through a resistor. The battery monitoring device monitors the voltage of each battery in real time and feeds back the result to determine whether equalization is needed.

6. A balance management system for rapid detection and control of SOC equalization according to claim 2, characterized in that: The main control unit MCU uses a Freescale S12XS series microcontroller.

7. A balance management system for rapid detection and balance control of SOC balance according to claim 3, characterized in that: The slave control unit (SCU) uses a Freescale S12XS series microcontroller.

8. A balance management system for rapid detection and control of SOC equalization according to claim 2, characterized in that: The main control unit (MCU) includes a current acquisition module, which acquires the current of the lithium battery pack through a Hall current sensor.

9. A balance management system for rapid detection and control of SOC equalization according to claim 3, characterized in that: The slave control unit (SCU) includes a data acquisition and control module, which uses a voltage acquisition chip to acquire the voltage information of each battery in the lithium battery pack.

10. A balance management system for rapid detection and control of SOC balance according to claim 3, characterized in that: The slave control unit (SCU) controls the balanced charging and discharging of each battery through a switching chip based on the balanced charging and discharging control signal.

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