CN-122017621-A - Battery management system and method for redundant collection

CN122017621ACN 122017621 ACN122017621 ACN 122017621ACN-122017621-A

Abstract

The application relates to a redundant acquisition battery management system and method. The system comprises a first voltage acquisition unit, a second voltage acquisition unit and a control unit, wherein the first voltage acquisition unit is used for acquiring a first voltage of a target battery cell, and the second voltage acquisition unit is used for acquiring a second voltage of the target battery cell. The control unit is used for receiving the first voltage and the second voltage, and carrying out weighted fusion calculation based on the deviation between the first voltage and the second voltage to obtain a final voltage value of the target battery cell. By adopting the system, when the single-channel voltage acquisition fails due to interference or faults, the other channel of redundant acquisition and fusion algorithm is adopted to output accurate battery voltage, so that the fault tolerance of the voltage acquisition link and the reliability of the battery management system are effectively improved.

Inventors

FAN JICHAO
CHU JUNTAO
Zhou Dinghao
ZHANG XIANGWU

Assignees

双一力(宁波)电池有限公司

Dates

Publication Date: 20260512
Application Date: 20251231

Claims (10)

1. The battery management system for redundant collection is characterized by comprising a first voltage collection unit, a second voltage collection unit and a control unit, wherein the first voltage collection unit and the second voltage collection unit are respectively connected with a battery pack, and the battery pack comprises a plurality of electric cores; the first voltage acquisition unit is used for acquiring a first voltage of the target battery cell; the second voltage acquisition unit is used for acquiring a second voltage of the target battery cell; And the control unit is used for receiving the first voltage and the second voltage, and carrying out weighted fusion calculation based on the deviation between the first voltage and the second voltage to obtain a final voltage value of the target battery cell.
2. The system of claim 1, wherein the second voltage acquisition unit comprises a resistor divider network and a multi-path gating circuit, wherein the multi-path gating circuit is connected with the resistor divider network; The resistor voltage division network is connected with the battery pack and used for dividing the voltage of the battery pack and forming a plurality of voltage division nodes; The first voltage acquisition unit sends a gating command to the multi-path gating circuit, controls the multi-path gating circuit to gate the voltage division node corresponding to the target battery cell, and acquires the voltage value of the conducted circuit to obtain the second voltage.
3. The system of claim 2, wherein the control unit is configured to: and obtaining the second voltage of the target battery cell according to the difference value between the first total voltage corresponding to the first voltage dividing node gated at the current moment and the second total voltage corresponding to the adjacent voltage dividing node gated at the last acquisition moment.
4. The system of claim 1, wherein the first voltage acquisition unit comprises a first analog front end chip and the second voltage acquisition unit comprises a second analog front end chip, and wherein the first analog front end chip and the second analog front end chip perform voltage acquisition on the same power core through different voltage acquisition channels.
5. The system of any one of claims 1 to 4, wherein when the battery pack is in a charged or discharged state, the control unit is configured to: When any one of the first voltage and the second voltage is in jump opposite to the voltage change trend of other battery cells, and the other one of the first voltage and the second voltage is the same as the voltage change trend of other battery cells, the acquired voltage with the same change trend is taken as the final voltage.
6. The system of claim 5, wherein the control unit is further configured to: When the first voltage and the second voltage are in the same-direction jump, calculating moving average values of all cell voltage variation amounts of the battery pack at the current moment, respectively calculating deviation of jump values of the first voltage and the second voltage relative to the moving average values, distributing weights to the first voltage and the second voltage based on a comparison result of the deviation and a first preset threshold value, and carrying out weighted calculation to obtain the final voltage.
7. The system of claim 6, wherein the formula for weighted fusion calculation of the first voltage and the second voltage is: ; Wherein, the For the said final voltage to be applied, For the first voltage to be present in the first voltage, For the second voltage to be the same, For the jump value corresponding to the first voltage, For the jump value corresponding to the second voltage, And a threshold value is preset for the first.
8. The system of any one of claims 1 to 4, wherein when the battery pack is in a static state, the control unit is further configured to: Judging whether the first voltage and the second voltage generate jump with the amplitude exceeding a second preset threshold value relative to the historical value of the first voltage and the second voltage, and taking the acquired voltage with the amplitude not exceeding the second preset threshold value as the final voltage.
9. A method of redundant collection battery management for a system as recited in any one of claims 1-8, the method comprising: acquiring a first voltage and a second voltage of a target battery cell in a battery pack; Calculating a deviation between the first voltage and the second voltage; And carrying out weighted fusion calculation based on the deviation to obtain the final voltage of the target battery cell.
10. The method of claim 9, wherein the performing a weighted fusion calculation based on the deviation to obtain a final voltage of the target cell comprises: when the first voltage and the second voltage are in the same-direction jump, calculating a moving average value of all cell voltage variation amounts of the battery pack at the current moment; calculating deviation of the jump values of the first voltage and the second voltage relative to the moving average value respectively; assigning weights to the first voltage and the second voltage based on a comparison result of the deviation and a first preset threshold; and carrying out weighted calculation on the first voltage and the second voltage according to the assigned weights so as to obtain the final voltage.

Description

Battery management system and method for redundant collection Technical Field The application relates to the technical field of battery management, in particular to a redundant acquisition battery management system and method. Background The Battery management system (Battery MANAGEMENT SYSTEM, BMS) is a core component for ensuring safe, stable and efficient operation of the Battery pack, and one of the core functions is to collect the voltages of the individual cells in the Battery pack. The accuracy of the voltage data is directly related to the reliability of the functions of state evaluation, balanced management, overcharge and overdischarge protection and the like of the battery. Currently, when the battery management system collects the battery voltage, a solution is generally adopted, which is implemented by using a single Analog Front End (AFE) chip and a sampling channel thereof. The scheme sequentially or synchronously measures the voltage of each cell through an analog-to-Digital Conversion (ADC) inside the AFE chip. However, in a practical application scenario, when the acquisition channel of the AFE chip is broken, electromagnetic interference occurs, and a single acquisition path may not obtain effective voltage data. And further influences the accurate judgment of the BMS on the battery state, and even causes risks such as misoperation of charge and discharge control, cell damage and the like. Therefore, how to improve the robustness and reliability of the voltage acquisition circuit under the interference and partial fault conditions and ensure to obtain accurate and usable cell voltage data becomes a technical problem to be solved in the field. Disclosure of Invention Accordingly, it is desirable to provide a redundant collection battery management system and method capable of improving the reliability of cell voltage collection. In a first aspect, the application provides a redundant collection battery management system, which comprises a first voltage collection unit, a second voltage collection unit and a control unit, wherein the first voltage collection unit and the second voltage collection unit are respectively connected with a battery pack, and the battery pack comprises a plurality of electric cores; the first voltage acquisition unit is used for acquiring a first voltage of the target battery cell; the second voltage acquisition unit is used for acquiring a second voltage of the target battery cell; And the control unit is used for receiving the first voltage and the second voltage, and carrying out weighted fusion calculation based on the deviation between the first voltage and the second voltage to obtain a final voltage value of the target battery cell. In one embodiment, the second voltage acquisition unit comprises a resistor voltage division network and a multi-path gating circuit, wherein the multi-path gating circuit is connected with the resistor voltage division network; The resistor voltage division network is connected with the battery pack and used for dividing the voltage of the battery pack and forming a plurality of voltage division nodes; The first voltage acquisition unit sends a gating command to the multi-path gating circuit, controls the multi-path gating circuit to gate the voltage division node corresponding to the target battery cell, and acquires the voltage value of the conducted circuit to obtain the second voltage. In one embodiment, the control unit is configured to: and obtaining the second voltage of the target battery cell according to the difference value between the first total voltage corresponding to the first voltage dividing node gated at the current moment and the second total voltage corresponding to the adjacent voltage dividing node gated at the last acquisition moment. In one embodiment, the first voltage acquisition unit comprises a first analog front end chip, the second voltage acquisition unit comprises a second analog front end chip, and the first analog front end chip and the second analog front end chip acquire voltages of the same power core through different voltage acquisition channels. In one embodiment, when the battery pack is in a charged or discharged state, the control unit is configured to: When any one of the first voltage and the second voltage is in jump opposite to the voltage change trend of other battery cells, and the other one of the first voltage and the second voltage is the same as the voltage change trend of other battery cells, the acquired voltage with the same change trend is taken as the final voltage. In one embodiment, the control unit is further configured to: When the first voltage and the second voltage are in the same-direction jump, calculating moving average values of all cell voltage variation amounts of the battery pack at the current moment, respectively calculating deviation of jump values of the first voltage and the second voltage relative to the moving average values, distributing weights to