一种双路输出不间断直流电源的设计

A Design of Double-Output Uninterrupted DC Power Supply

针对不间断中小功率电源的需求,设计了两路输出分别是4.2 V和12 V的不间断直流电源。主要由多路输出正-反激变换器、Buck充电电路、单环稳压控制电路及锂电池放电切换电路组成。具体实现方法是,市电正常供电时,通过UC3845芯片控制正-反激变换器实现三路电压输出,其中两路分别是4.2 V和12 V的稳压输出,另一路输出由ARM控制给锂电池分阶段充电。在市电断电时,通过ARM智能控制继电器使锂电池切换到放电状态,利用同一个变压器再次通过反激变换器方式实现两路稳压输出,并且由ARM控制器采用PID算法实现主路输出的稳定。完成相应的仿真和实验验证,结果表明了电路设计和控制方法的正确性,实现了不间断双路输出直流电源各项技术指标。

In view of the demand of uninterrupted power supply,a new DC power supply with two outputs of 4.2 V and 12 V is designed.It is mainly composed of multiple output forward-flyback converter,Buck charging circuit,single loop stabilized voltage control circuit and lithium battery discharge switching circuit.The specific implementation method is that three roads output are realized by forward-flyback through the UC3845 chip control when the main power supply is on.And two of them respectively is 4.2 V and 12 V voltage output,one output is controlled by the ARM to the lithium battery charging in stages.When the main power is off,the lithium battery discharge through ARM intelligent control relay switch,and using the same transformer again through the voltage output flyback mode to realize two roads output.The PID algorithm is adopted by ARM controller to realize the stability of the output of the main road.The simulation and experimental verification have been completed.The results show the correctness of the circuit design and control methods,and the technical indexes of uninterrupted dual circuit DC power supply are realized.