Application of extended participation factors to detect voltage fluctuations in distributed generation systems

The dynamics of distribution systems has been significantly modified by the increasing penetration of distributed generation in distribution grids. Distribution systems, with distributed synchronous generators, may exhibit dynamic characteristics similar to those observed in transmission systems, such as, for example, low-frequency electromechanical oscillations. The impacts related to electromechanical oscillations raise important concerns about the system stability and power quality across the distribution grids. Tools usually employed to analyze such kind of oscillations in transmission systems (such as participation factors, for example), may not be fully appropriate for analyzing this same phenomenon in distribution systems. Due to the aforementioned issues, this work proposes the use of extended participation factors as a tool to detect voltage fluctuations caused by electromechanical oscillations in distributed generation systems. The results of a case study show that, in some cases, the traditional participation factors are not able to detect these fluctuations, while the extended participation factors performed well with respect to this detection.