基于电流馈电拓扑的车载直流变换装置研制

分析了电压馈电推挽全桥电路和电流馈电推挽全桥电路的特点,设计了一种基于电流馈电拓扑的车载高频隔离开关稳压电源。该电源以电流型控制芯片KA3846为控制核心,采用双闭环的控制方法,设计了PWM发生电路、驱动电路、保护电路以及双闭环控制电路,而且系统具有软启动、封锁输出脉冲、过流等保护功能。系统测试结果表明,该电源结构简单、工作可靠、成本低。

Development of DC Conversion Devices Based on Current-fed Topology

The characteristics of the voltage-fed push-pull full-bridge circuit and the current-fed push-pull full-bridge circuit were analyzed,a high frequency isolation switching power supply was designed based on the current feed topology.The current-mode control chip KA3846 was used as control core of the power and the dual closed-loop control method was used,a PWM generating circuit,drive circuit,the protection circuit and double-loop control circuit were designed.The power has a soft-start,block output pulse,overcurrent protection and other functions.System test results show that the power structure is simple,reliable,and with low cost.