ROBUST DAMPING CONTROL DESIGN FOR UPFC USING MIXED H2/Hinfinite TECHNIQUE

Power systems such as the other industrial plants contain different kinds of uncertainties which should be considered in controller design procedure. For this reason, the idea of robust mixed H2/H? control was used for designing of Unified Power Flow Controller (UPFC) Power Oscillation Damping (POD) controller. This newly developed design strategy combines the advantage of the H2 and H? control synthesizes and gives a powerful multi-objectives design addressed by the Linear Matrix Inequality (LMI) techniques. To achieve decentralization, using the Schauder fixed point theorem the synthesis and analysis of Multi-Input Multi-output (MIMO) control system is translated into set of equivalent Multi-Input Single-Output (MISO) control system. The proposed mixed H2/ H? controller has a decentralized scheme and advantage of a decentralized controller design is reduction in the controller complexity and suitability for practical implementation. The effectiveness of the proposed control strategy was evaluated under operating conditions for damping low frequency oscillations in comparison with the classical controller to demonstrate its robust performance through nonlinear time simulation and some performance indices.