Dynamic Phasor Finite Element Modeling of Grid-Connected DFIG Considering Winding Space Harmonics

Abstract

This paper presents a new technique for quantifying the winding MMF space harmonics of wind-driven Doubly-Fed Induction Generator (DFIG) for power quality assessments. Instead of following the commercial electromagnetic transient programs in modeling electric machines using lumped-parameters models, the paper uses a combined Dynamic Phase modeling and Finite Element Method (FEM) to model the generator accurately while reducing the computational burden and simulation time associated with the conventional time-stepped finite element analysis. The technique has the ability to efficiently model core nonlinearity and stator/rotor MMF space harmonics. The results of a C++ code written by the authors of the new dynamic phasors FEM technique are compared to the conventional time-stepping FEM to show the capability of the method to produce comparable results in shorter simulation time.