A new simple and high performance digital peak current mode controller for DC-DC converters

Abstract

This paper introduces a novel digital peak current mode controller for dc-dc converters. In the proposed controller, the inductor current is reconstructed using the average value of inductor current, the input voltage, and the output voltage. All measured values for the controller are sampled at low sampling rate (equal to switching frequency), allowing use of low speed and low cost analog to digital converters; consequently high frequency noise cannot enter into the control loop. Also, a compensation slope can easily be added to the current loop to tune the controller and stabilize the system. The theory of controller operation is described in the paper, also the function of control blocks inside the controller are discussed briefly. The proposed controller is implemented in an FPGA, and an isolated full bridge boost converter is built to evaluate the controller performance. The experimental results verify the validity of proposed method.