A high-precision current monitoring circuit for power battery management

Abstract

The invention discloses a high-precision current monitoring circuit for power battery management. The existing technology cannot solve the problem of zero drift of the circuit caused by the residual magnetism of the current sensor and the temperature drift of the operational amplifier. The zero drift phenomenon reduces the monitoring current. accuracy, the present invention includes a linear Hall current sensor, a micro relay, an MCU, a first operational amplifier U1, a second operational amplifier U2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a Five resistors R5, sixth resistor R6, seventh resistor R7, eighth resistor R8, and ninth resistor R9; the present invention performs an automatic zero-adjustment operation after each circuit is powered on and in a static state of the battery to ensure that the current monitoring circuit The output offset voltage is close to zero during operation, thus improving the accuracy of monitoring current.

Description

technical field [0001] The invention relates to the technical field of power battery management, in particular to a high-precision current monitoring circuit. Background technique [0002] Current is an important parameter in the management process of power batteries, and the accuracy of current directly affects the accuracy of battery state of charge estimation. With the change of the battery working environment and the extension of the working time, the residual magnetism of the Hall-type current sensor becomes more and more obvious, and the ambient temperature is also changing all the time, so the circuit will have zero drift and temperature drift, etc., which will affect the accuracy of the current. Although the existing current sensors have good linearity and high sensitivity, they cannot solve the problems of zero drift and temperature drift in the circuit. Contents of the invention [0003] The purpose of the present invention is to overcome the deficiencies of the...

AI Technical Summary

Problems solved by technology

With the change of the working environment of the battery and the extension of the working time, the residual magnetism of the Hall-type current sensor becomes more and more obvious, and the ambient temperature is also changing all the time, so the circuit will have zero drift and temperature drift, etc., which will affect the accuracy of the current.

Although the existing current sensors have good linearity and high sensitivity, they cannot solve the problems of zero drift and temperature drift in the circuit

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