A MOHBMO Based SSSC Compensator for Power System Stability Enhancement

In this paper, the modified linearized Phillips-Heffron model is utilized to theoretically analyse a singlemachine infinite-bus (SMIB) installed with SSSC. Then, theresults of this analysis is used for assessing the potential of an SSSC supplementary controller to improve the dynamic stabilityof a power system. This is carried out by measuring theelectromechanical controllability through singular value decomposition (SVD) analysis. This controller is tuned forsimultaneously shifting the undamped electromechanical modes to a prescribed area in the s-plane. The issue of designing arobustly SSSC-based controller is considered and formulated as an optimization problem according to the eigenvalue-based multi-objective function consisting of the damping ratio of the undamped electromechanical modes and the damping factor. Next, considering its high capability to find the most optimisticresults, the Honey Bee Mating Optimization (HBMO) algorithm is used to solve this optimization problem. A wide range ofoperating conditions are considered in design process of the proposed damping controller in order to guarantee the its robustness. The effectiveness of the proposed controller isdemonstrated through eigenvalue analysis, controllability measure, nonlinear time-domain simulation and someperformance indices studies. The results show that the tuned HMBO based SSSC controller which is designed by using the proposed multi-objective function has an outstanding capabilityin damping power system low frequency oscillations, also it significantly improves the power systems dynamic stability.