Robust Control of Isolated Microgrid based on Decentralized Fixed Structure H${\infty}$ Loop Shaping

Abstract

The use of isolated microgrids to provide electric energy to remote areas has recently increased; isolated microgrids allow making use of local energy resources, especially the renewable ones. Frequency fluctuations remain one of the main problems in isolated microgrids, this fluctuation is accentuated as the percentage of renewable energies increase in the microgrid which can affect stability and performance. This research presents a control technique for reducing frequency deviation in an isolated microgrid composed of Renewable Energy Sources (RES).In the presence of high degrees of uncertainty, Decentralized Fixed structure robust H infinity loop shaping controllers are presented to maintain frequency deviation to a minimal and provide effective disturbance rejection. Particle Swarm Optimization is utilized to acquire controller parameters for decentralized Fixed structure H infinity loop shaping controllers, and the obtained results are compared to the traditional H infinity controller to show the high performance and stability of the proposed control technique.