Coordinated Control of EPT and Generator Excitation System for Multidouble-Circuit Transmission-Lines System

A new optimal coordinated control strategy between an electronic power transformer (EPT) and generator excitation is proposed to improve power system dynamic performance and stability. The studied system is based on a single-machine multidouble-circuit transmission-lines (SMTL) system. In the SMTL system, the generator is connected to an infinite bus through a conventional power transformer with a double-circuit transmission line, and to another infinite bus with an EPT with a double-circuit transmission line. The mathematical model of the SMTL system is established, and the proposed optimal coordinated control strategy is upon linear optimal control theory. Numerical simulations were carried out for the SMTL system, and the simulation results showed that the proposed control strategy has good dynamical performance for a variety of disturbances, and can improve the system damping and voltage performance effectively.