Design of H∞ - Controller for a reduced order linearized power electronic cricuit [articol]

Abstract

Most of the systems in our daily life consist of power electronic circuits. They are micro circuits which are difficult to be analyze because the circuit consists of nonlinear elements. This paper deals with one of the power electronic circuit, boost converter. The non-linear elements of the converter circuit are linearized. The obtained linearized converter circuit is a higher order model. Designing a controller for this higher order model is complex and simulation time also increases. So, efficient order reduction techniques have been used to reduce the system order. The reduced order system is now used to design a controller. H-infinity method is used to design a PI and PID controller for load voltage control of the converter circuit. Conventional PID and ZN PID controllers were also been developed for comparison with H-infinity based controllers. H-infinity techniques have the advantage over classical control techniques in that, they are readily applicable to problems involving multivariate systems with cross-coupling between channels. Performances of these controllers were compared in terms of settling time. The models are simulated using MATLAB 13.0 simulink software. Simulation results show that hankel was a better method for order reduction depicting same characteristics for higher and lower order models. H-infinity based PID controller show better results compared to other controllers.