Best Input-Location Pair Selection for SSR Damping Controller in DFIG Based Wind Farms

Mitigation of Sub-Synchronous Resonance (SSR) in Doubly-Fed Induction Generator (DFIG) based wind farms by incorporating a Supplementary Damping Controller (SDC) to the existing DFIG converter controllers is more economical than providing additional FACTS devices to the system. The performance of the SDC highly depends on its location and the Input Control Signal (ICS) selected. Hence, a systematic method for selecting the best ICS- location pair for SDC is the need of the hour. Hence in this paper, a technique to identify the best ICS- location pair for SDC based on the right half-plane zero method, relative gain array method, and Henkel singular value is proposed. The performance of the proposed strategy is then compared with that of the generally used residue-based selection method and joint geometric controllability method. A proportional feedback controller based on the root locus method is designed to validate the results of the proposed method. Extensive simulation studies using MATLAB/Simulink are carried out to evaluate the performance of the proposed method.