Monitoring device and monitoring methods for distributed battery management system

Abstract

The invention discloses a monitoring device and a monitoring method in a distributed-battery management system. The monitoring device comprises a loop structure and an isolation structure, wherein the loop structure comprises a low-voltage loop and a high-voltage loop; the high-voltage loop comprises an operational amplifier circuit which is integrated by use of single chips with high common mode rejection ratio and adopts a differential inputting-amplifying processing structure; and the isolation structure comprises a communication isolation chip adopting a transformer isolation structure. The monitoring method comprises the steps of receiving a signal, judging whether the signal is received or not, performing initialization settings, acquiring high-voltage loop data, performing transformer-type isolated transmission, processing low-voltage loop data, sending data and judging whether an exit condition is met. Through a technical proposal in the invention, the monitoring device and the monitoring method realize high security, reliability and extremely high accuracy in a battery monitoring process, as well as continuous rapid sampling, and have no special requirements on power supply sources.

Description

technical field [0001] The invention relates to the technical field of management of automobile batteries, in particular to a monitoring device and a monitoring method in a distributed battery management system. Background technique [0002] In recent years, with the advancement of automobile technology, hybrid technology has gradually matured from development, and the monitoring and management of battery status in hybrid electric vehicles and electric vehicles is one of the keys to hybrid technology. How to quickly, accurately and reliably Measuring the characteristic parameters of the battery, such as voltage and temperature, is a difficult point in hybrid technology. [0003] Because the distributed battery management system has the advantages of high reliability and good scalability, it is applied to the management system of batteries in hybrid electric vehicles and electric vehicles. like figure 1 As shown, it is a typical distributed battery management system, and th...

AI Technical Summary

Problems solved by technology

[0005] Method 1: Use analog isolation devices (linear optocoupler, analog isolation op amp) for measurement; in this method, the isolation voltage can be made higher and the linearity is good, but the cost is high, and the static current of the optocoupler is large. Control its Static current leads to complex circuits; the inconsistency of the optical conductivity of optocoupler devices leads to low absolute accuracy, and software is required to correct almost every unit to achieve better accuracy. Therefore, this method is very cumbersome and not suitable for Batch use;

[0006] Method 2: Use an operational amplifier with high common-mode voltage, such as INA117 measurement; in this method, the accuracy can be made higher, and the performance better than 1% can be achieved by using a 0.1% precision resistor, but due to the need to use high voltage Power supply, resulting in low efficiency and high device cost. In many cases, it is required to connect the high-voltage ground with the low-voltage ground or have a direct electrical connection, because there is a large leakage current between the high-voltage power and the low-voltage ground, which has a certain potential safety hazards, so the safety of the whole vehicle circuit is low, which limits the application of this method

Images