Akademik Veri Yönetim Sistemi
Çukurova Uluslararası Multidisipliner Çalışmalar Kongresi, Adana, Türkiye, 13 - 16 Aralık 2018, ss.188-197
DC-DC converters are widely used in today's world with their vairous qualities such as high power density, good response speed, a wide range of output voltage value. Buck type DC-DC converter is a power electronics circuit that converts input voltage level into a voltage level lower than the input voltage level. It is possible to find numerous types of DC-DC converter topologies. Converter types are classified by their circuit functions based on their input-output voltage levels. Basic DC-DC converter structures are buck, boost and buck-boost converters. Unlike linear circuit topologies, modelling of DC-DC converter circuits are very difficult because of their switched structure. The main problems are to model semiconductor switches, to identify various circuit structures and model the converter following an analysis of the states. The stability of a control system designed for a buck DC-DC converter depends on dynamic modeling. State-space model and system modeling are effectively used in converter designs. The required transfer function is obtained thanks to a small signal analysis of the system modeled using state-space model at a certain operating point. In optimal controlling methods, the controller parameters based on the transfer function of the controlled system are minimized using a known error criterion. There are many studies using different types of controllers in the literature for the control of the buck type DC-DC converter. There are many studies in the literature where classical PI and PID controllers are not sufficient for system response. Therefore, Linear Quadratic Regulator (LQR) control technique is proposed for optimal control of the buck type converter. In this study, a control system circuit model was created in Matlab / Simulink program by obtaining the transfer function of the buck type converter with the state space small signal analysis method. Later, reference voltage and output load of the buck type DC-DC converter were varied to compare dynamic performances of classical PI and LQR controllers.