多路输出反激式开关电源的设计与仿真

Design and simulation of multi-channel output flyback switching power supply

在多路输出电源系统的研究中,多路的设计一般是通过增加高频变压器绕组来实现,通常只能对主路输出进行反馈调节,辅路往往达不到调节效果,会产生交叉调整率的问题。采用UCC28C43控制芯片设计了一款5 V/2 A、12 V/1 A、15 V/0.5 A的三路输出反激式开关电源,在输出电压发生改变时,通过调节PWM输出保证电源的稳定性。此外,为了改善负载的调整率,还对开关电源设计了零-极点补偿网络和基于加权电压反馈的双闭环反馈回路。在二者的共同作用下,负载调整率有了显著的改善。最后,运用PSpice仿真软件对开关电源的整体电路进行了建模设计,验证了本设计的正确性。

In the research of multi-channel power supply system,the design of multi-channel was generally realized by adding high-frequency transformer windings,but only the output of the main circuit could be adjusted by feedback usually.The auxiliary circuit often fails to achieve the adjustment effect,which will lead to the problem of cross adjustment rate.A three-channel flyback switching power supply with 5 V/2 A,12 V/1 A and 15 V/2 A was designed using UCC28C43 control chip.When the output voltage changes,the stability of the power supply was ensured by adjusting the PWM output.In addition,in order to improve the load regulation rate,a zero-pole compensation network and a double closed-loop feedback loop based on weighted voltage feedback were designed for the switching power supply.Under the joint action of them,the load regulation rate had been significantly improved.Finally,the whole circuit of switching power supply was modeled and designed by using PSpice simulation software to verify the correctness of this design.