Power system transient stability analysis with integration of DFIGs based on center of inertia

As power systems experience increased wind penetration, an effective analysis and assessment of the influence of wind energy on power system transient stability is required. This paper presents a novel center of inertia (COT) approach to understand how integrated doubly fed induction generators (DFTGs) affect the transient dynamics of a power system. Under the COT coordinate, the influence of integrated DFTGs is separated into the COT related and individual synchronous generator related parts. Key factors that affect the COT's dynamic motion as well as the rotor dynamics of each individual synchronous generator with respect to the DFTG integration are investigated. To further validate the analysis, comparative simulations of three different scenarios with varying DFTG capacities, access locations, and the replacement of synchronous generators are conducted. The results show that the dynamics of the COT and the individual generators are affected by the integrated DFTGs via different mechanisms, and are sensitive to different variables in the DFTG's integration condition.