The Analysis, Modeling, and Control of the Forward DC/DC Converter

This article deals with the analysis and control of the DC/DC converters. The objective is to summarize a simple procedure to express the power converter’s control transfer function and to show its usability possibilities. The process of obtaining this transfer function includes the creation of a state space description of the given system. As an example of the use of the transfer function of the control, the design of the feedback controller constants can be mentioned, since it is a transfer function that has a non-negligible effect on the closed loop system, or there is also the possibility of the stability verification. The state space model, as well as the transfer function, are derived for both ideal and non-ideal cases of topology. For the nonideal topology, at least some parasitic parameters are considered. For the design of the constants of the controller, an application “Control System Designer” in Matlab was used, enabling their design based on various criteria. Additionally, a comparison of the transfer functions based on frequency characteristics is presented. The Forward type topology is given as an example providing the benefit of output galvanic isolation.