Design of Double Closed Loop in Boost Aerospace DC-DC Power Supply

A boost dc-dc space power supply is implemented using single-phase active PFC dedicated control chip L4981B, and the converter utilizes the traditional PFC control principle and reserves the advantages of L4981B. It includes power stage and control stage, and the latter consists of the peripheral circuit of L4981B, output voltage closed loop and input current closed loop. In the paper, the main task is to modify and optimize the design of double closed loop to meet the special requirements of space environment and other several different loads. Consequently, a prototype is realized with continuous current mode, high output voltage stability, good load regulation factor and excellent EMI characteristics. It also features that the switching frequency is 50 kHz, the input voltage range is 50 V_DC to 90 V_DC the rated output DC voltage is 128 V_DC with a low ripple and the output power capability is 1.5 kW