高精度锂离子电池电压采集系统设计

Design of high precision battery voltage acquisition system

针对锂离子电池组单体电池电压采集精度问题,设计了优化的串联电压采集系统。该系统首先通过光耦电路将电池动态加载到母线上,然后利用74HC595移位控制寄存器采集单体电池电压,再经信号转换、隔离电路处理,最后由S TM32F103ZET6 AD模块处理。与一般的电压采集系统相比,设计的电压采集系统硬件电路更为简化,软件操作简单,所测电压误差均值、方差更小,单体电压测量精度在4 mV以内。系统稳定性更好,采集精度更高,有广泛的工程适用价值。

In order to improve the voltage measurement accuracy of lithium-ion cells,an optimized serial bus voltage acquisition system was designed.In the system,the photoelectric relay circuit was adopted to load a cell on the measurement bus dynamically;the voltage was measured by means of the logic control of shift register 74HC595,followed by the processing of signal conversion and isolating circuit,and finally,the processing of STM32F103ZET6 analogue-to-digital conversion module.Compared with the common voltage acquisition systems,the proposed voltage acquisition system has the advantages of simple hardware circuit,convenient software operation,and smaller mean error and variance of measured voltage,and the voltage measurement accuracy of cell is within 4 mV.The system has better stability and higher accuracy,and is easy to expand,meeting the demand of practical application.