基于单片机的磷酸铁锂电池组充放电电路设计

Design of charging and discharging circuit for lithium iron phosphate battery pack based on single chip microcomputer

设计了磷酸铁锂电池组的充放电电路,主电路为双向直流-直流变换电路,控制电路是以单片机STC12C5A60S2为核心的.为了实现对磷酸铁锂电池组的充、放电的控制,输入、输出电压和电池组电流信号经过调理电路后,送入单片机,利用单片机片内10位模数转换器转变为数字信号,在单片机中利用数字PI算法,输出47 kHz的脉冲调制信号去控制主电路中的开关管实现电压、电流的闭环控制.通过电路实验验证了所设计充放电电路具有功能齐全、调节方便、效率高、稳流精度高等优点.

The charging and discharging circuit of the lithium iron phosphate battery pack is designed.The main circuit is a bidirectional DC-DC conversion circuit,and the control circuit is based on the STC12C5A60S2.In order to control the charging and discharging of the lithium iron phosphate battery pack,the input and output voltage and battery pack current signals are sent to the single-chip microcomputer after the conditioning circuit.The on-chip 10-bit analog-to-digital converter of the single-chip microcomputer is used to convert into digital signals.Using digital PI algorithm,output 47kHz pulse width modulation signal to control the switch tube in the main circuit to achieve closed-loop control of voltage and current.The experimental results show that the designed charging and discharging circuit has the advantages of complete functions,convenient adjustment,high efficiency and high precision of current stabilization.