An Analytical Model for Detailed Transient Fault Analysis of Doubly-Fed Induction Machines

Abstract

This paper presents an exact analytical solution to the two-phase and three-phase short-circuit events of the doubly-fed induction machine (DFIM). The contribution is intended to strengthen the predictability of DFIMs under the design stage or for control tuning purposes and reduce the computational costs of large-scale transient stability studies of the interconnected power system. In general, the approach enables to simplify and improve the analysis DFIMs. The original analytical equations are derived from first principles. A case study of a doubly-fed induction generator (DFIG) is considered, where the "large machine approximation" is shown to be valid as well. The analytical equations are used to predict the torque transients in different handpicked transient scenarios and assessed against numerical simulations. Finally, the proposed analytical model shows excellent agreement with the numerical results in the SIMSEN environment.