Assessment of Flicker Emission in a Grid Connected Wind Farms

Wind farms in Tamil Nadu's Coimbatore district have identified several issues, including flickering emissions, frequent generator tripping, and power evacuation issues caused by a weak grid. Taking into consideration the scarcity of research on flickering emissions, this work focuses on the causes of short-term flicker severity (Pst) in wind farms that export generated power to industrial loads. To identify the scenarios that cause flickering, simulation models of fixed speed wind farm and variable speed wind farm with controllers were developed using DIgSILENT power factory software. The flicker emissions were measured at the wind farm substations using Fluke and Dranetz PX5.8 power quality analyzers in accordance with the IEC 61400-21 standard. To validate the simulation model, the results from the flickermeter during the simulation and the field measurements were compared. According to the results of this research, both fixed and variable speeds produce flicker emissions that exceed the IEC standard limit, that causes the power electronics-based industrial drives to fail to operate. The controllers were developed to improve the performance of wind farms that will benefit the current and future wind energy-efficient conversion systems.