Representation of variable speed wind turbine generators for short circuit analysis

Type 3 (doubly-fed asynchronous) and Type 4 (full conversion) wind turbine generators provide much more flexible operation and increased efficiency due to power electronic converters employed in their circuit. The short-circuit characteristics of these wind turbines are complex because of these power electronic circuit and the controls of the power conversion system. This paper presents the short-circuit current characteristics of these machines under different operating conditions and provides an approach to represent these characteristics in short-circuit analysis.