Time Domain Study of a Type-3 DFIG Wind Turbine's Dynamics: Q Drop Function Effect and Attraction VS Control Limits Analysis

In this paper, a type-3 Doubly Fed Asynchronous/Induction Generator (DFAG/DFIG) wind turbine is considered for a dynamical study. The main blocks of the model taken from the literature are described and translated into a system of differential equations. By proving the possibility of eliminating the algebraic constraint, we are provided with good numerical possibilities to study wind turbine's dynamics. The paper provides a time domain analysis to emphasize and analyze the effect of adding a Q Drop function to the reactive power control dynamics. Our results, supported by simulations, suggest the important impact of the Q Drop function on the integrators blocks. The paper also provides an investigation of the system's attraction limits versus the control limits proposed by General Electric and others. The results, supported by simulations, questions the current models' validity, at least the proposed control limits.