Robust Positive Position Feedback Controller for Voltage Control of Islanded Microgrid

This paper presents the design of robust positive position feedback (PPF) controller to control the grid voltage for an islanded microgrid. The microgrid consists of several distributed generators (DG) and local loads which is partially unknown and uncertain. The controller is designed in a way that it shows the robustness against unmodeled loads, dynamic loads and harmonic loads. The dynamics of the plant is identified using differential equations. The design of the controller is presented based on negative imaginary approach. The simulation results presented in the paper show that the controller provides extensive improvement in the voltage control of islanded microgrid under different uncertainties.