Nonlinear Control for Three Phase Single Stage Grid Connected PV System

This paper presents a new control methodology for three phase single stage grid connected photovoltaic system. Based on a synchronized nonlinear model of the whole system, backstepping controller was proposed for the three-phase inverter in order to ensure the operation of the PV system at the maximum power point with unity power factor. Grid synchronization has been provided by a three-phase 2
^nd
order Phase-Locked Loop. The stability is demonstrated by means of Lyapunov analysis and evaluated under changing atmospheric conditions using Matlab/Simulink environment, the simulation results clearly demonstrate the performance provided by backstepping controller.