An Aggregated Model of a Large Wind Farm with Variable-Speed Wind Turbines Equipped with Doubly-Fed Induction Generators

Abstract

One of the main concerns of grid-integration of large wind farms with variable-speed wind turbines equipped with doubly-fed induction generators controlled by back-to-back converters is a possible risk of mutual interaction between the control systems of the converters. This topic is discussed and illustrated by simulations on a large wind farm model consisting of eighty wind turbines, when subjected to a short-circuit fault. At no mutual interaction, the wind turbines show coherent response at the grid fault. In such a case, large wind farms can be represented by one-machine equivalent, e.g. one wind turbine model with re-scaled power capacity. This simplification can be applied for voltage stability investigations carried out on detailed models of large power systems.