带均衡功能的电压采集模块设计和实现

Design and implementation voltage acquisition board with equalization function

由于单体锂电池之间存在不一致性而影响其使用性能,因此在电池管理系统中须设置均衡模块。基于Freescale单片机设计并实现了20路带均衡功能的动力锂电池电压采集模块。该电压采集模块采用高速光耦进行单路选通;单体电池的电压经差分滤波电路、A/D转换电路以及单片机处理后用CAN总线发送给电池管理系统的主控模块。经实验验证该采集模块的性能稳定,充电完成后的电池一致性提高。

The performance of batteries was influenced because of inconsistencies among the monomer lithium battery. So the equalization module in the Battery Management System was necessary. The 20-channel power lithium battery voltage acquisition module with equalization function was designed and implemented based on Freescale microcontroller. High-speed optocoupler for single channel strobe was used in voltage acquisition module. After the acquisition of the differential filter circuit, conversion of A/D conversion circuit and processing of MCU, the single battery voltage was sent to the BMS main control module by CAN Bus. The acquisition module＇s stably performance was validated, and the battery consistency after being charged was improved.