Optimal parameter coordination of power system stabilizers in multi-machine power systems employing Harmony Search

Power system stabilizers (PSSs) play an important role in suppressing low frequency oscillations. In multi-machine power systems, the objective of optimal PSS parameter tuning should not only be to damp electromechanical modes strongly related to the pertained generator, but also to take the damping status of other generators into account. Taking this in mind, a new assessment criterion from the perspective of generators is proposed based on the well-known eigenvalue analysis. An objective function reflecting the overall stability as well as the damp distribution among generators is developed. The Harmony Search (HS), an effective modern heuristic optimization algorithm developed in recent years, is employed for solving this constrained optimization problem. Finally, a software system is designed and implemented for applications to practical power systems. Two power systems, i.e. the New England 10-unit 39-bus system and the 64-unit 305-bus Fujian power system are served for demonstrating the feasibility and efficiency of the developed model and method.