A Novel Grid Integration scheme for the Hybrid Electric Power generation using Solar and Wind Energy Resources

In this paper is reported a novel grid integration scheme for a hybrid electric power generation scheme using Photovoltaic power generation and induction generator based wind power generation. The proposed scheme adopts Fuzzy Logic Control ( FLC) for the Maximum Power Point Tracking ( MPPT) of the wind turbine driven induction generator and the incremental conductance based MPPT for the solar PV system. The power from the wind source and the photo voltaic source are brought to a common DC link and a DC to AC three phase inverter is used to upload power into the grid and a novel control scheme is adopted for sinusoidal current injection at the point of grid integration. The first novelty of the proposed system is that a variable frequency drive is used to run the induction generator at different synchronous speeds for power generation over a wide wind speed range. The additional novelty of the proposed scheme is that a direct Clark transformation and a set of two PI controllers are used to control the grid integration inverter enabling it to drive grid current with THD levels much less than the allowable limits.