Estimation of Wind Farms Working in Presence of Voltage Dips Using the IEEE Std. 1459-2000.

Connection of wind farms to the electric network is submitted to some grid codes, which establish wind farm working conditions in presence of some transient phenomena, such as voltage dips. In this paper, Spanish grid code is used to evaluate effects of voltage dips on wind farms working. Reactive powers and currents must be watched at wind generators submitted to voltage dips, thus reactive phenomena are analyzed. For the study, Budeanu´s and Emanuel3s approaches, both included in the IEEE Standard 1459-2000, are applied. Results, experimentally tested at actual wind farms, show that Emanuel´s explain reactive phenomena rather than Budeanu´s in unbalanced voltage dips, since first approach leads to decompose reactive power into the reactive powers due to the reactive loads and due to the unbalances. This last reactive power can reach comparable effects to those caused by the reactive loads. Also, these two reactive powers can be added or compensated.