Daisy chain communication fault diagnosis method and device and battery management system

Abstract

The invention discloses a daisy chain communication fault diagnosis method and device and a battery management system. The method comprises the following steps: if an internal loop opening command issent to the n-th unit of a daisy chain, detecting that the communication state of the daisy chain is communication interruption and sending an internal loop opening command to the (n-1)-th unit; if itis detected that the communication state of the daisy chain is normal, determining that the n-th unit or a communication line between the n-th unit and the (n-1)-th unit breaks down; or, if the internal loop opening command is sent to the nth unit, starting the n-th unit; and determining that a communication line between the (n + 1)-th unit or the nth unit and the (n + 1)-th unit breaks down after detecting that the communication state of the daisy chain is normal communication and sending an internal loop opening command to the (n + 1)-th unit and detecting that the communication state of the daisy chain is communication interruption. By adopting the embodiment of the invention, the working state of each node in the daisy chain can be independently detected, and the position where daisychain communication is interrupted can be quickly positioned.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a daisy chain communication fault diagnosis method and device, and a battery management system. Background technique [0002] In the topological architecture of the distributed battery management system, a separate sampling unit performs voltage and temperature detection, equalization management and diagnosis on the module. There are two networking methods for distributed communication: Controller Area Network (CAN) bus and daisy chain communication. In the daisy chain communication, each unit is serially connected by a daisy chain. At the end of the last unit, a loopback line is used to send the signal back to its own receiving interface, so that the communication forms a closed loop. Compared with CAN bus, daisy chain communication has the advantages of low cost and high data synchronization, but any communication failure between units will cause communication interruption o...

AI Technical Summary

Problems solved by technology

After the daisy chain communication fails, the entire network cannot perform data transmission, and cannot obtain sampling and diagnostic information

[0003] At present, after encountering a daisy chain communication failure, you can use the replacement method, that is, replace the sampling units in the battery pack with normal sampling units one by one to find the faulty parts; you can also use test tools to test whether each sampling unit is working normally , but these investigation methods are complex to operate, high-pressure environment has great potential safety hazards and low efficiency

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