Linear Quadratic Integral Voltage Control of Islanded AC Microgrid Under Large Load Changes

This paper proposes a new secondary voltage controller for an islanded, inverter-based microgrid having unequal line impedances. The controller is designed based on linear quadratic integral (LQI) control. The objective of the controller is to regulate voltage following extreme disturbances such as very large load changes which might cause the system's voltage to fall below accepted voltage deviations. The proposed controller shows superior performance when compared to a PI controller tuned using the Ziegler-Nicholas method.

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