Investigation on doubly fed induction generator wind energy conversion system

Abstract

newline newlineThe use of Renewable Energy Resources (RESs) in modern power systems has become a new trend to address the rising energy generation requirement. Increased power demands and requirements of green and clean energy encourage energy generation via solar and wind-based RESs. Their sustainability attracts increased penetration and is an alternative to decreasing traditional energy resources. High penetration of RES into the existing electricity structure poses significant new challenges. Therefore, it is necessary to explore the opportunities and challenges facing of integration of these RES to the grid. These RESs provide better voltage regulation and reduce losses. The technical challenges come into play due to changes in operational philosophy, like control and protection of the systems. Wind Energy is the most prominent source of intermittent energy resources. Variable-speed wind turbines with Doubly Fed Induction Generators (DFIGs) surge new concerns towards system stability, protection issues and power quality issues in the new generation era. newlineWind Turbines include power electronic converters at the grid interface. With the presence of power electronic devices, the Wind Generators (WGs) have low inertia in comparison to conventional Synchronous Generator (SG). Insufficient inertia in the WT system creates frequency instability in the grid-connected system. Moreover, Doubly Fed Induction Generator-Wind Turbines (DFIG-WTs) are more sensitive to faults. It suffers from the problem of disconnection from the grid during fault conditions. This thesis focuses on stability related issues that mainly appear in transient fault conditions. Transient stability is actually serious concern in grid-connected DFIG-WT. Low Voltage Ride Through (LVRT) is an inevitable feature of Wind Energy Conversion System (WECS) for its successful integration with the interconnected power system. A lot of literature is available to support enhancing the Low Voltage Ride Through of DFIG-WF.