Modeling of Dual Excited Synchronous Generator with slip frequency excitation

Abstract

Wind power generation is considered to be the significant dispatchable source in the integrated grid. Integration of wind firms impose serious frequency fluctuations in the grid due to intermittent wind speed variations. Doubly-fed induction generator (DFIG) and permanent magnet synchronous generator (PMSG) based wind power generation with suitable control strategy has become popular for solving frequency related issues in the grid. In this paper, constructional features of dual excited synchronous generator (DESG) are investigated for regulating the frequency fluctuations in the grid. DESG has two field windings one is on the d-axis and the other is on q-axis. Since, the construction of field windings on both the axes abide lot of efforts, two different ways of constructing field windings (DESG-1 and DESG-2) are suggested in this paper. In DESG-1, the two field windings are arranged with some angular deflection and in DESG-2, the two field windings are separated by 90°. The two windings in both DESG-1 and DESG-2 must be excited as per their arrangement to get the synchronous frequency at the stator terminals. The performance of aforementioned DESGs with different speeds is investigated in MAXWELL software.