This paper presents a robust stabilization scheme for a three-phase grid-connected photovoltaic system to control the current injected into the grid and dc-link voltage to extract maximum power from photovoltaic (PV) units. The scheme is mainly based on the design of a robust controller using a partial feedback linearizing approach of feedback linearization, where the robustness of the proposed scheme is ensured by considering uncertainties within the PV system model. In this paper, the uncertainties are modeled as structured uncertainties based on the satisfaction of matching conditions. The performance of the proposed stabilization scheme is evaluated on a three-phase grid-connected PV system in terms of delivering maximum power under changes in atmospheric conditions.
- Grid-connected photovoltaic (PV) system
- matching conditions
- nonlinear controller
- partial feedback linearizing scheme
- structured uncertainty