Analysis and UTDQ Control Design for Alleviation of Subsynchronous Resonance Using STATCOM

Subsynchronous resonance (SSR) is a drastic phenomenon in electrical power generation that is disastrous to both electrical and mechanical systems as the exchange of energy between the two systems take place. This paper proposes a novel control design based on unit templates and d-q (UTDQ) transformations for static synchronous compensator (STATCOM) to alleviate SSR oscillations. The efficacy of the proposed control design is validated through time domain analysis of IEEE second benchmark model taken as test system. State space analysis of the the mechanical system is formed for eigenvalue analysis, that provide the different torsional modes and their corresponding frequencies. Frequency scan of electrical network is carried out at different compensation levels for obtaining the corresponding resonant frequencies. The level alleviation of SSR achieved with the proposed control design is 97.27 % which is highly compelling as compared to other studies in the literature.