新型开关稳压电源的优化设计与实现研究  

Research of Optimal Design and Implementation for a New Switching Power Supply

作　　者：陈富军[1] 衡耀付[1] 季钢 

机构地区：[1]黄淮学院电子科学与工程系,河南驻马店463000 [2]驻马店供电公司,河南驻马店463000

出　　处：《河南大学学报（自然科学版）》2010年第4期357-360,共4页Journal of Henan University:Natural Science

基　　金：河南省科技发展计划项目(092102210305)

摘　　要：针对小功率开关电源所普遍存在的问题,实现了一种新型小功率高频开关稳压电源的优化设计.电路中的输入回路EMI滤波器设计,有效解决了电网谐波问题以及电源本身对电网污染的问题;控制部分利用电流式PWM控制器UC3842芯片直接控制大功率开关MOSFET管,并通过电压反馈和电流反馈双环控制功能,实现了占空比的精确调节,提高了转换速率,降低了导通损耗;电路采用线性光耦PC817来改变误差放大器的增益,而且在电压采样反馈电路中采用了集成运放PJ324CD芯片以及三端可调稳压管TL431,使得输出电压在负载发生较大的变化时,输出电压基本保持稳定.For the common problem of low-power switching power supply,this paper introduces an optimal design for a new low-power high-frequency switching power supply.The input loop circuit EMI filter design effectively to solve the problem of power harmonics and pollution of the switching power itself to the grid;Control section using current-mode PWM controller UC3842 chip directly to control the MOSFET power switch tube,through the double-loop control of voltage feedback and current feedback,which achieves precise adjustment of the duty cycle,and then improves the conversion rate and reduces conduction losses.Not only using a linear optocoupler PC817 changes the gain of the error amplifier,but also an integrated op-amp PJ324CD chips and three-terminal adjustable voltage regulator tube TL431 are used in the voltage feedback circuit samples.The design makes the output voltage basically stable even when the load has a greater change.

关 键 词：EMI滤波器 电流式PWM控制器 UC3842 电磁兼容性 

分 类 号：TN86[电子电信—信息与通信工程]