On the Assessment of Power Qaulity Characteristics of Grids Connected Wind Energy Conversion Systems

Abstract

This paper presents a wind park power quality tool, developed in MATLAB, following the specifications contained in IEC 61400-21 standard, being the flickermeter model constructed according to IEC 61000-4-15 standard. Wind energy dedicated procedures and methodologies, such as the concept of fictitious grid and the two different modes of operation -continuous and commutated -are then applied in accordance with IEC 61400-21 standard. In order to test all the functionalities and proper behaviour of the developed tool, a casestudy from which power quality related data is available, was selected. Some simulation results obtained with the developed software tool are presented with the main objective of illustrating the methodologies that have been followed in its development. Furthermore, the validation of the model implemented in the WECS power quality tool is performed against the results obtained by the certified institution that was involved in the power quality tests of Samos Island, in Greece.

Investigation for Causes of Poor Power Quality in Grid Connected Wind Energy - A Review

“…[8]Simultaneous tripping of many distributed generators due to a voltage quality disturbance (like a voltage dip) is the subject of active discussion. [9] Due to increase in number of grid connected induction generators, there is needed to compensate this effect. There is increase in total harmonics distortion (current) with number of grid connected induction generators.…”

“…Recent analysis and study [8] shows that the impact of the yaw error and horizontal wind shear on the power (torque) and voltage oscillations is more severe than the effects due to the tower shadow and vertical wind shear. [21] A literature survey [9] of the new grid codes adopted for wind power integration has identified the problems of integrating large amounts of wind energy to the electric grid. It suggests that new wind farms must be able to provide voltage and reactive power control, frequency control and fault ridethrough capability in order to maintain the electric systems stability, For the existing wind farms with variable speed, double-fed induction generators (DFIG) and synchronous generators (SG),a frequency response in the turbine control system can be incorporated by a software upgrade.…”