Measurement-based system identification and multi-input PSS design for damping electromechanical oscillations

This paper presents a methodology to identify the state-space model of power system from measured input-output data and then to design a robust controller for damping electromechanical oscillations in power systems. The designed controller is a power system stabilizer (PSS) that stabilizes one key subsynchronous (SSR) mode and a local mode contributing to critical electromechanical oscillations involving turbine-generators and electrical network. The IEEE First Benchmark Model (FBM) for the analysis of SSR phenomena has been considered in this study. Stability of the system is discussed through eigenvalue analysis. The controller designed has ensured good damping to subsynchronous modes which were otherwise very poorly damped