OPTIMIZING LQR TO CONTROL BUCK CONVERTER BY MESH ADAPTIVE SEARCH ALGORITHM

Abstract

In this study, control method to control Buck converters by Linear Quadratic Regulator (LQR) controllers is employed. Systems with conventional LQR controllers present good stability properties and are optimal with respect to a certain performance index. However, LQR control does not assure robust stability when the system is highly uncertain. In this paper, a convex model of converter dynamics is obtained taking into account uncertainty of parameters. In order to apply the LQR control in the uncertain converter case, the performance index is optimized by using Mesh Adaptive Search (MADS). As a consequence, a new robust control method for dc–dc converters is derived. This LQR-MADS control is compared with normal LQR design. All the analysis and simulations on the above converter is by MATLAB software. The simulation results show the improvement in voltage output response.