Extended State Observer-Backstepping Control for Grid-Tied PV System

As a distributed energy source, the photovoltaic system will affect the stability of the power grid in the grid connected operation mode. To meliorate the control effect of the inverter and the power quality of the grid connected photovoltaic microgrid, a control strategy based on the backstepping method is designed for the grid connected inverter of the photovoltaic system. Firstly, the dynamic model of the photovoltaic system is given, and the unmodeled parts are appended. Secondly, on the basis of backstepping method, the unmodeled amount is compensated by extended state observer, and an arbitrary-order fixed-time differentiator is employed to solve the "computational complexity" problem. Finally, the stability of the system is proved by the Lyapunov theory. The simulation results verify the advanced property of the proposed controller.