Countermeasures to Subsynchronous Resonance Problems

Investigation of Subsynchronous Resonance (SSR) problems by several utilities and manufacturers has resulted in proposed and applied methods to mitigate or eliminate SSR damage to turbine-generator sets. This paper presents some of the solutions proposed without regard for their general desirability. Each solution describes the method and/or devices used, theory of operation, strengths and weaknesses, and operating experience. The paper could be used as a starting point for detailed investigation of alternate countermeasures to a particular SSR problem.