Design of a dual output voltage, constant current SEPIC-boost converter with PID feedback control

In this paper, design of a dual output DC-DC converter based on combination of SEPIC and boost topology is presented. A simple control strategy is achieved by using a single switch to drive both SEPIC and boost circuitry resulting in an economical, simple and practical design. Two different output levels, namely 36 V and 48 V with similar 2 A constant current are successfully generated from a 24 V input supply. Feedback control is applied using Proportional - Integral – Derivative (PID) control where conventional and optimised gain values are integrated in the proposed design. The results show both methods able to produce the desired output levels, but the optimised gain parameters yield better regulation with smaller ripple percentage.