一种反激式开关电源的设计与仿真

Design and Simulation of a Flyback Switching Power Supply

为实现小功率开关电源的小型化、高效化和低成本,提出了一种基于电流型PWM芯片UC3842控制下双路输出的反激式开关电源。研究了电源的拓扑结构和工作原理,详细分析了EMI滤波器和整流滤波电路、功率变换电路、PWM控制电路、反馈检测电路的关键参数和设计过程。利用Saber软件的仿真工具箱搭建了电路闭环仿真模型,模拟反激式电路的环路控制,实现两路直流输出5V/1A和15V/1A,效率高达90%。仿真结果证明了设计的正确性和可行性。

For the realization of small switching power supply miniaturization, high efficiency, and low cost, a flyback switching power supply controlled dual output was designed based on the current-mode PWM chip UC3842. The topological structure and working principle of the power supply were studied. The key parameters and the design process of EMI filters and rectifier filter circuit, power conversion circuit, PWM control circuit, feedback detection circuit were analyzed in detail. Using the simulation toolbox of Saber software to build the closed-loop simulation model, simulating the loop control of the flyback circuit and achieving the two-channel DC output of 5 V/1 A and 15 V/1 A,the efficiency can reach 90%. The simulation results prove the correctness and feasibility of the design.