Mitigation of SSR in Power System through Power Control of Additional DFIG

Abstract

This paper presents a direct power control strategy and its effect on sub-synchronous resonance
(SSR) for doubly fed induction generator (DFIG) - based wind generator. When the synchronous
generator undergoes a SSR, it will exchange power with series capacitor of transmission line. DFIG
has power convertors in its rotor circuit, with the help of fast switching of IGBTs of rotor convertor
circuit, fast control on active and reactive power of DFIG can be possible. The main objective of this
paper is to examine the capability of DFIG to give active power and reactive power during SSR as
per need. Apart from original test system, additional DFIG is included in test system and during subsynchronous resonance its performance is analyzed without and with supplementary control signal
from the synchronous generator. The analysis of SSR has been carried out based on transient
simulation using MATLAB Simulink and eigenvalue analysis using D-Q model test system. The DFIG
rotor convertor control to damp multimodal SSR oscillations comprises independent model control.
The test system created from the system adopted from IEEE first benchmark model