In the following book, you will find general methods for designing FACTS supplementary controllers for power oscillations damping. You will also find some other related publications in my profile as well as the literature.
Haggi, H., Marjani, S. R., & Golkar, M. A. (2017, May). The effect of rescheduling power plants and optimal allocation of STATCOM in order to Improve power system static security using TLBO algorithm. In 2017 Iranian Conference on Electrical Engineering (ICEE) (pp. 1120-1125). IEEE.