PNNL

Abstract

This project, Wide-area Oscillation Analysis and Trending Study, is sponsored by the Office of Electricity (OE) of the Department of Energy (DOE) who tasked Northwest National Laboratory (PNNL) to conduct this research. Staff of Federal Energy Regulatory Commission (FERC) have been involved in the project as observers and have provided advisory comments and suggestions. The primary objective of this study is to assess whether there are significant trends in the wide-area oscillatory behavior with respect to the significant generation-mix changes brought by the increased penetration of RES in the WECC system. The work performed in this project is considered to be complimentary to previous work by NERC/industry and covers the aspects that have not been studied or trended before. The trending analysis presented in this report can serve as reference for future grid planning and operation of the WECC system. In this report, how the changes in the generation mix can impact the frequency and damping ratio (DR) of WECC wide-area oscillation modes has been studied. Thorough data-based and model-based analyses have been carried out to analyze the current trends and then extended to evaluate the oscillation behaviors of the future WECC system.