  This article proposes an application of a derisking methodology of
subsynchronous torsional oscillations considering a realistic use case. The
main objective is to summarize and draft a synthetic paper clarifying the
complete methodology highlighting the main information needed step-by-step. For
exemplification, a real model from a decommissioned oil power plant is adopted,
where a fictitious high voltage direct current power link is connected. In this
article, stress is laid on details of the application of the derisking methods:
the unit interaction factor and the complex torque coefficients method. Then,
the different steps to obtain results are explicitly explained. Moreover, the
design and tuning process of supplementary subsynchronous damping controller is
discussed. This mitigation section uses minimal information to correctly damp
the unstable oscillations, as one would expect from industrial projects where
the data sharing may be limited. Finally, the resources needed to perform each
step of the study were summarized.
