Subsynchronous Control Interaction Study Framework and Applications to Southern California Edison System

The paper proposes a Subsynchronous Control Interaction (SSCI) study framework and applies to Southern California Edison System. Frequency impedance scan screening is performed for a large set of contingencies on the entire power network and the severity of the contingencies is ranked based on the damping coefficients. The outcome of these screening and ranking can identify those short-listed scenarios which need to undergo detailed Electromagnetic Transient (EMT) analysis. Based on the screening and ranking results, an EMT model for both a small power network around the Point of Interconnection (POI) and the detailed Distributed Energy Resources (DER) model using EMT/PSCAD are developed. It concludes that the screening techniques and the EMT type time domain analysis are complementary with respect to the investigation of SSCI issues.