Designing closed-loop controllers using a MatlabP<sup>®</sup> dynamic model of the Zeta converter in DCM

Abstract

As is well known the Zeta converter is a fourth-order system. Therefore, the selection of the type of feedback controllers and its design, it is not an easy task. Usually many restrictions must be met in closed-loop control systems. For instance, it is necessary ensure system stability, as well as, guarantee that transient and steady-state responses are under preset limits. In order to design a controller (P, I, PD, PI, PID, Lead, Lag, Lead-Lag), is usually necessary to know the system plant. However, unfortunately, the system plant is not always available and even when it is accessible, designers must have good knowledge of control systems theory in order to design properly the controllers. Aiming to make the compensators design a simpler task to everyone this paper presents a computational model of the dynamic behavior of the Zeta converter working in discontinuous conduction mode, as well as, two design examples of feedback controllers. Two compensators were designed using MATLAB® and SIMULINK® specifically by means of the design optimization library, which could be used thanks to the computational model of the Zeta converter. It was performed a set of simulations using the PSIM® software, in order to validate the proposed computational model. The obtained results confirm that the computational model of the dynamic behavior of the Zeta converter in DCM is useful to design feedback controllers and also to reduce the development time of the compensators.