Damping Enhancement of a Multi-machine System Using a Generalized Unified Power Flow Controller (GUPFC)

Tóm tắt

This paper presents the design procedures of two proportional-integral-derivative (PID) damping controllers for a generalized unified power flow controller (GUPFC) to achieve damping improvement of a four-machine system. Two PID damping controllers of the proposed GUPFC are designed to contribute adequate damping characteristics to the dominant modes of the system under various operating conditions. A frequency-domain approach based on a linear system using eigenvalue analysis and a time-domain method based on nonlinear-model simulations subject to a three-phase short-circuit fault at the transmission line is systematically performed to examine the effectiveness of the proposed control schemes. It can be concluded from the comparative simulated results that the proposed GUPFC joined with the designed PIDs can improve the stability of the system subject to a severe disturbance.