Robust Control of Inter-area Oscillations in a Multimachine Network Employing LMI Based Wide Area TCSC Controller

This paper proposes a Linear Matrix Inequality (LMI) based robust controller design method for enhancement of damping of inter-area oscillations in a multimachine power system network. A Four-input, Single-output (FISO) controller is designed for a Thyristor Controlled Series compensator (TCSC) employing Wide Area Measurement (WAM) based stabilizing signals as generator speed. The major concern of signal transmission delay in wide area measurement is overcome here using the novel concept of Synchronized Speed Phasor Measurement (SSPM) with Global Position Satellite System (GPS) technology. The controller design has been carried out based on the mixed-sensitivity formulation in a LMI framework with pole-placement constraint. The small signal stability performance of the controller has been examined employing eigenvalue as well as time domain analysis for different operating scenarios of a 14-area real power system comprising of 24 numbers of generators, 203 buses and 266 lines. The designed controller has been found to be robust against varying generation and load power demand as well as for transmission line outage.