Characterization and assessment of voltage and power constraints of DFIG WT connected to a weak network

This article thoroughly investigates the challenges and constraints raised by the integration of a Doubly-fed Induction generator wind turbine, DFIG WT, into an ac network of extensively varying parameters and very weak conditions. The objective is to mitigate the voltage variations at the point of common coupling, PCC, and maximize the wind power penetration into weak networks. As a basis of investigation, a simplified system model is utilized and the respective PCC voltage, active and reactive power stability issues are identified. Besides, a steady-state study for DFIG WT connected to a weak grid is presented and qualitative conclusions about the system inherent interactions and typical restraints are presented and discussed. The impact of the wind power feed-in and the reactive power flow on the PCC voltage is assessed under widely varying system parameters. Results verification is performed via MATLAB/SIMULINK platform to assure the obtained steady-state study conclusions.