Investigations on Strong Resonance in Multimachine Power Systems With STATCOM Supplementary Modulation Controller

Abstract

The phenomenon of strong resonance that is noticed in systems with mode coupling is characterized by coincidence both of eigenvalues and eigenvectors. It is necessary to consider the effect of strong resonance on the coupled modes while designing a damping controller for a system. The work presented in this paper aims at investigating the behavior of two oscillatory modes in the neighborhood of strong resonance in power systems in the presence of a STATCOM damping controller. The modes that interact near the point of strong resonance are identified. The concept of multi-modal decomposition is applied to isolate the swing mode (SM) of interest. The relevant exciter mode (EM) is identified from the knowledge of participation factors. The method of perturbations suggested by Seiranyan to study the interaction of the eigenvalues near the point of strong resonance is modified suitably to make it applicable to systems with feedback controller. The illustrative examples include three-and four-machine systems.

Proposed mechanism for performance of power system stabilizers in the condition of strong resonance

“…Therefore, it is important to investigate the effect of stabilizers parameters on the above mentioned variations while trying to stabilize system oscillations in the condition of strong resonance. Reference [7] presents a similar investigation in power system examples.…”

“…Padiyar and Saikumar [7] have investigated the strong resonance in power systems with STATCOM supplementary damping controller. Examples of 3-and 4-machine show that variations of the controller parameters cause two modes to pass near a strong resonance.…”

Effects of strong resonance in multimachine power systems with SSSC supplementary modulation controller

“…Equations (2) and (3) with subscript f for the matrices represents the full system. Equations (2) and (3) with subscript f for the matrices represents the full system.…”

“…The relevant hyperbolae are constructed by making suitable modifications based on the theory suggested by Seiranyan [5] and the work presented by Padiyar [2], and then the asymptotic movement of the two oscillatory system modes is then studied as one of the parameters varies. The effect of strong resonance on these oscillatory modes can sometimes be a concern for the system stability.…”

H∞ Loop Shaping Based Robust Power System Stabilizer for Three Machine Power System

“…For the system considered this procedure yields three stabilizers one at each machine. Using participation factor technique [16] …”