Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)


Electrical and Computer Engineering


YangQuan Chen


This work presents a new control strategy using fractional order operators in threephase grid-connected photovoltaic generation systems with unity power factor for any situation of solar radiation. The modeling of the space vector pulse width modulation inverter and fractional order control strategy using Park’s transformation are proposed. The system is able to compensate harmonic components and reactive power generated by the loads connected to the system. A fractional order extremum seeking control and “Bode’s ideal cut-off extremum seeking control” are proposed to control the power between the grid and photovoltaic system, to achieve the maximum power point operation. Simulation results are presented to validate the proposed methodology for grid-connected photovoltaic generation systems. The simulation results and theoretical analysis indicate that the proposed control strategy improves the efficiency of the system by reducing the total harmonic distortion of the injected current to the grid and increases the robustness of the system against uncertainties. Additionally, the proposed maximum power point tracking algorithms provide more robustness and faster convergence under environmental variations than other maximum power point trackers.