Fault Current Calculation for DFIGs Under Complete Fault-Ride Through Strategies

The fault current characteristic of doubly fed induction generators (DFIGs) is determined by both the external grid voltage and the internal rotor voltage. However, there are multiple fault-ride through strategies employed by DFIGs. In this paper, a fault current calculation method for DFIGs under complete fault-ride through strategies is proposed. The transient behavior of the DFIG is described by the state space model in which the stator voltage and rotor voltage are selected as input signals. The internal dynamics of the DFIG is modeled by the rotor voltage which is controlled by multiple strategies in sequence. Comparative case studies are carried out to demonstrate the accuracy of the proposed method.