Robust Nonlinear Controller Design for DC–AC Converter in Grid-Connected Fuel Cell System

This article presents a robust nonlinear controller for distributed fuel cell in the three-phase grid-connected system. A partial feedback linearization scheme is applied to linearize the grid-connected fuel cell system. The mismatches between the actual system and the dynamical model are considered uncertainties. The noise decoupling capability of the feedback linearized control scheme is also demonstrated. A loop-shaping-based
$\text{H}_\infty$
mixed-sensitivity controller is designed for the partially linearized plant of the grid-connected fuel cell system. Performance of the designed controller is investigated under power factor changes, three-phase short-circuit fault, parameter variation, and measurement noise in a hardware-in-loop simulation platform with OP 4510.