Austin February 2016 Luncheon

"SSR for Dummies"

Recent expansion of the ERCOT 345kV transmission system included the addition of dozens of new double-circuit transmission lines with series compensation. This expansion introduced concerns that subsynchronous resonance (SSR) interactions between the series capacitors and the torsional systems of existing generator units could lead to events that cause damage to those units. This presentation will describe, at a high level, what SSR is and discuss the differences between electrical stability, torsional stability, and transient torque amplification issues that may arise from SSR interactions. It will also discuss the methods being employed by the industry today to assess the risks associated with SSR, and when necessary the technologies used to mitigate those risks.

Our speaker Bruce English is Technical Director for GE Energy Consulting. He has spent 16 years with GE designing and applying series capacitor banks, performing system studies associated with all aspects of series compensation (including SSR studies) and other EHV transmission system equipment application and planning studies. He has designed, applied, and invented several products that mitigate the risks of SSR interaction. Mr. English has been active in IEEE and CIGRE and was Vice Chair of the IEEE working group that recently published IEEE Standard 1726-2013, IEEE Guide for the Functional Specification of Fixed-Series Capacitor Banks for Transmission System Applications.