On the Extraction of Input and Output Impedance of PWM DC-DC Converters

Abstract

The buck, buck-boost and boost converter, are the most popular types of DC-DC converters. The input/output characteristics of these converters operating in Continuous Current Mode (CCM) is the object of considerations in this paper. The input impedance of converter helps the designer to select a suitable energy source for the converter. The internal impedance of selected input energy source must be quite lower than the input impedance of converter in order to avoid any voltage drop. The output impedance of DC-DC converters must be quite small in order to supply the load with high current demand. So, extraction of input/output characteristics of DC-DC converters is an important task and helps the designer to decide about the performance of system. Extraction of input/output characteristics is using pencil-and-paper analysis is quite tedious and error prone. This paper show how input/output impedance of DC-DC converters can extracted with the aid of MATLAB® programming. This paper can be used as a tutorial on the extraction of input/output impedance of DC-DC converters.