Simultaneous Operation of a PSS and a Series Power Electronics-Based Controller with Minimum Interaction

Simultaneous use of power system stabilizers (PSSs), and series power electronics-based controllers such as static series synchronous compensators (SSSC) have recently found applications in power oscillation damping improvement. However, the potential interaction among the PSS and the SSSC damping controllers can result in poor damping control of both devices. In this paper a multivariable model for simultaneous operation of an SSSC and a PSS is developed. Based on this model, and by using the concept of the minimization of the column dominance measure, a multi-input multi-output (MIMO) controller is designed to minimize the interaction among the control variables of the two devices. The feasibility of the proposed modeling and control in decoupling the control schemes of the two devices are validated by simulation. Furthermore, simulation results from the proposed control technique are compared to those from the traditional control approaches, and the superiority of the proposed scheme in improving the power oscillation damping as well as the dc-link voltage regulation is illustrated