CN-122001074-A - Dual-source redundant power supply method and distributed battery management system

CN122001074ACN 122001074 ACN122001074 ACN 122001074ACN-122001074-A

Abstract

The invention provides a double-source redundant power supply method and a distributed battery management system, wherein the system comprises at least one battery management chip, each battery management chip is connected with a single power cell in a one-to-one correspondence manner; the battery management chip comprises a battery core data sampling module, a data processing module, a first communication module, a first power supply module, a second power supply module, a switching and fault awakening module and a battery core fault bypass protection module. By adopting the system provided by the invention, even if faults such as over-discharge, internal short circuit, open circuit and the like occur to the corresponding battery core, the chip can still continuously work through the redundant power supply channel, so that the working such as full-dimension data acquisition, fault diagnosis, protection execution and reporting of the fault battery core are completed, and the monitoring blind area of the battery pack is effectively eliminated.

Inventors

CHEN XIANGRONG
LI TAISHI
XU JIANJUN
LI LINGHUA

Assignees

郴州新能源电池材料研究中心
郴州市尚亿新能源有限公司
郴江实验室

Dates

Publication Date: 20260508
Application Date: 20260409

Claims (10)

1. A distributed battery management system, comprising: Each battery management chip is connected with a single battery cell in a one-to-one correspondence manner; a control module; a battery pack low voltage redundant power bus; wherein, the battery management chip includes: the battery core data sampling module is used for acquiring battery core data of the corresponding battery core; The data processing module is connected with the electric core data sampling module and is used for processing the electric core data; the first communication module is connected with the data processing module and is used for sending the processed electric core data to the control module; the first power module is respectively connected with the corresponding battery cell and the data processing module to form a main power supply path and is used for receiving initial voltage output by the battery cell, boosting the initial voltage and providing main power supply voltage for the data processing module; The input end of the second power supply module is connected with the low-voltage redundant power supply bus of the battery pack to form a redundant power supply path, and the second power supply module is used for performing voltage conversion processing on bus voltage input by the bus and outputting redundant power supply voltage; The switching and fault awakening module is respectively connected with the first power supply module, the second power supply module, the data processing module and the first communication module and is used for presetting a power supply strategy with priority of a main power supply path, monitoring the working state of the main power supply path in real time, executing switching to a redundant power supply path when detecting that the main power supply path is abnormal, and also receiving an awakening instruction of the control module, driving the second power supply module to start and awakening the battery management chip; And the battery cell fault bypass protection module is respectively connected with the data processing module, the corresponding battery cell and the battery cell series circuit of the battery pack, and is used for cutting off the fault battery cell from the battery cell series circuit according to the driving instruction of the data processing module in a redundant power supply mode.
2. The distributed battery management system of claim 1, wherein the second power module comprises: The voltage conversion unit is used for performing buck conversion on the bus voltage input by the low-voltage redundant power supply bus of the battery pack and outputting an intermediate voltage; The overvoltage and overcurrent protection unit is connected in series between the low-voltage redundant power supply bus of the battery pack and the voltage conversion unit and is used for triggering protection when overvoltage or overcurrent is input or output and cutting off power supply; the starting control unit is respectively connected with the voltage conversion unit and the switching and fault awakening module and is used for driving the voltage conversion unit to start or shut off according to an awakening instruction or a switching control signal; And the output filtering unit is connected with the output end of the voltage conversion unit and is used for filtering the intermediate voltage and outputting stable redundant power supply voltage.
3. The distributed battery management system of claim 1, wherein the switch and wake-up-by-failure module comprises: the state monitoring subunit is respectively connected with the input end and the output end of the first power supply module and is used for collecting the input state and the output state of the main power supply channel in real time; The switching control subunit is respectively connected with the state monitoring subunit and the switching switch subunit and is used for presetting a power supply strategy with priority of the main power supply path, and generating a switching control signal when detecting that the main power supply path is abnormal; The switching sub-unit is respectively connected with the output end of the first power supply module, the output end of the second power supply module, the data processing module and the first communication module and is used for responding to the switching control signal to perform seamless switching between the main power supply path and the redundant power supply path so as to provide continuous and stable power supply for the data processing module and the first communication module; And the wake-up logic subunit is respectively connected with the first communication module and the start control unit of the second power module and is used for receiving a wake-up instruction issued by the control module, driving the second power module to start and waking up the battery management chip.
4. The distributed battery management system of claim 3 wherein the wake-up logic subunit is further configured to, when the main power supply path is completely powered off and the output voltage of the battery core is 0V, respond to the wake-up instruction of the control module, drive the second power module to continuously output the redundant power supply voltage, so that the battery management chip enters a fault diagnosis mode, and complete acquisition, diagnosis and reporting of fault data of the battery core.
5. The distributed battery management system of claim 1, wherein the cell fault bypass protection module comprises: The semiconductor bypass switch is connected in series between the corresponding battery cell and a battery cell series circuit of the battery pack; the switch driving subunit is respectively connected with the data processing module and the control end of the semiconductor bypass switch and is used for controlling the on and off of the semiconductor bypass switch according to the driving instruction of the data processing module; and the loop detection subunit is respectively connected with the battery cell serial loop and the data processing module and is used for monitoring the loop state in real time and triggering overcurrent protection.
6. The distributed battery management system of claim 1, wherein the control module comprises: The second communication module is in communication connection with the first communication module of the battery management chip; the microcontroller is used for receiving the battery cell data and the fault information sent by the battery management chip through the second communication module and sending a control instruction and a wake-up instruction to the battery management chip through the second communication module; and the control module power supply unit is respectively connected with the microcontroller and the second communication module and is used for supplying power.
7. The system of claim 6, wherein the second communication module comprises a second wireless communication unit, the second wireless communication unit is matched with the first wireless communication unit in the first communication module to realize wireless data interaction, and the control module is further connected with an auxiliary power conversion module of the low-voltage redundant power supply bus of the battery pack and used for controlling power supply output of the low-voltage redundant power supply bus.
8. A dual source redundant power supply method for use in a distributed battery management system as claimed in any one of claims 1 to 7, comprising the steps of: s1, presetting a power supply strategy with priority of a main power supply path, and providing main power supply after boosting by a first power supply module through a corresponding battery core when a battery management chip works normally; s2, monitoring the input state and the output state of the main power supply channel in real time, and judging whether the main power supply channel is abnormal or not; S3, when the abnormality of the main power supply channel is detected, switching to a redundant power supply channel, and supplying power to the battery management chip through the second power supply module by using the low-voltage redundant power supply bus of the battery pack; S4, under a redundant power supply mode, the battery management chip continuously collects the battery core data of the corresponding battery core and performs fault diagnosis; And S5, when the battery cell is diagnosed to have a fatal fault, driving the battery cell fault bypass protection module to cut off the fault battery cell from the battery cell serial circuit, and reporting fault information to the control module to trigger a whole battery pack protection strategy.
9. The method of claim 8, further comprising step S6, when the main power supply channel is completely powered off and the output voltage of the battery core is 0V, the battery management chip receives the wake-up instruction issued by the control module and enters a fault diagnosis mode to complete data acquisition, diagnosis and reporting of the fault battery core.
10. The method of claim 8, wherein the determining conditions for the fatal faults of the battery cells in step S5 include at least one of internal short circuit of the battery cells, sudden drop of 0V of the battery cell voltage, severe overdischarge of the battery cells, and continuous deterioration of the internal resistance of the battery cells beyond a preset threshold.

Description

Dual-source redundant power supply method and distributed battery management system Technical Field The invention relates to the field of battery management systems, in particular to a dual-source redundant power supply method and a distributed battery management system. Background The Battery management system (Battery MANAGEMENT SYSTEM, BMS) is a core control component of the power Battery of the new energy automobile, and is responsible for collecting, analyzing and protecting state data such as voltage, current, temperature, internal resistance and the like of the Battery pack, and directly determining the use safety, cycle life and whole automobile performance of the power Battery. Currently, the mainstream BMS architecture is divided into two types, centralized and distributed. The centralized BMS monitors multiple strings of series-connected battery cells by adopting a single management chip, and has the defects of high-voltage tolerance requirement, large energy loss, complex wiring harness, loss of data of the whole package caused by chip failure and the like. Aiming at the problems, a distributed BMS architecture is gradually developed in the industry, for example, in a battery management chip and a system, a single battery cell is adopted to correspond to the distributed architecture of the single battery management chip, the chip is powered by the output voltage of the corresponding battery cell through a booster circuit, the high voltage of series connection of multiple battery cells is not required, the production process requirement of the chip is reduced, the use of sampling wiring harnesses and connectors is reduced, and the flexibility of the system is improved. However, the above prior art solutions still have the following fatal drawbacks that cannot be overcome: 1) The battery management chip only depends on the corresponding battery core to supply power, when faults such as over-discharge, internal short circuit, open circuit and the like occur in the battery core, the output voltage of the battery core is lower than the working threshold value of the chip and even is reduced to 0V, the chip is directly powered off, the monitoring, diagnosis and protection capability of the fault battery core is completely lost, a monitoring blind area of a battery pack is formed, and fault expansion and even thermal runaway accidents are extremely easy to occur; 2) The chip is powered by the battery cell booster circuit, when the booster circuit has undervoltage, failure and short circuit faults, the chip is powered off, no power supply redundancy backup exists, the monitoring function of the battery cell is completely lost due to single-point faults, and the functional safety level is insufficient; 3) When the battery core has fatal faults such as internal short circuit, open circuit and the like, a hardware-level bypass isolation mechanism is not provided, and the fault battery core can form open circuit in a series circuit or continuously worsen and collapse the whole string of battery packs, so that the whole battery pack is invalid and the fault tolerance is extremely poor; 4) When the battery core is completely powered off, the chip cannot be awakened remotely, offline diagnosis cannot be carried out on the fault battery core during after-sale maintenance, the whole battery core can be disassembled and inspected, the maintenance cost is extremely high, and early warning and tracing of faults cannot be realized. Therefore, there is a need to develop a distributed battery management system with dual-source redundant power supply, seamless switching, fault bypass protection and remote wake-up functions, which thoroughly solves the above defects of the prior art and meets the highest functional safety level requirement of the vehicle-mounted BMS. Disclosure of Invention Based on the technical problems set forth above, the invention provides a dual-source redundant power supply method and a distributed battery management system, which solve the fatal problems of power failure and complete loss of monitoring and protecting capabilities of a corresponding management chip caused by single-cell faults in the prior art, and improve the safety of a vehicle-mounted BMS. In particular, according to one aspect of the present invention, there is provided a distributed battery management system including: Each battery management chip is connected with a single battery cell in a one-to-one correspondence manner; a control module; a battery pack low voltage redundant power bus; wherein, the battery management chip includes: the battery core data sampling module is used for acquiring battery core data of the corresponding battery core; The data processing module is connected with the electric core data sampling module and is used for processing the electric core data; the first communication module is connected with the data processing module and is used for sending the processed electric core data to the control