Improving power quality of wind energy conversion system with unconventional power electronic interface

The increasing interest to utilize wind energy as a power source prompted more researches to be dedicated to the unconventional integration of this power source into the current grid. In this paper, one avenue to achieve this efficient utilization, through the use of integrated wind energy conversion system (WECS) using doubly fed induction generator (DFIG) is presented. Wind grid integration brings the problems of voltage fluctuation and harmonic distortion. This paper presents an Unconventional Power Electronic Interface (UPEI) to reduce the total harmonic distortion (THD) and enhance power quality during disturbances. The models used in the paper includes a pitch-angled controlled wind turbine model, a DFIG model, power system model and an UPEI having controlled converters. A phase to phase fault is simulated on 132 kV bus and the measured results obtained from grid connection of the wind generation system are presented. The results have demonstrated the ability of UPEI to regulate pitch angle, VAR and to reduce THD. The proposed system increases the effectiveness of the utilization of wind energy.

► We model DFIG wind turbine, power grid and unconventional power electronic interface. ► The control system is modeled to regulate pitch angle, generator speed and reactive power. ► Three cases are considered to analyse impact of adding wind turbines and UPEI in grid. ► Simulations are conducted using Matlab/Simulink and results of three cases are presented. ► Finally all the three cases are compared.