ACTIVE-POWER STABILIZERS FOR MULTIMACHINE POWER-SYSTEMS - CHALLENGES AND PROSPECTS

The problem of stabilizing a bulk power system by modulating controlla ble active loads is investigated. With today's advances in power distr ibution and home automation, fibre optic communications and networking , such a scheme for improving the reliability of bulk power supply is increasingly attractive. After developing a generic model for active l oad-modulation studies, time domain modal analysis is applied to a thr ee-machine-nine-bus system in order to assess quantitatively its respo nsiveness with respect to controller location and observed response si gnals. This structural analysis shows that proportional control is uns atisfactory and may artificially restrict the economic benefits of act ive-load modulation. By contrast, using the bus voltage and frequency as input signals, combined with suitable dynamic compensators, yields a fully decentralized, two loop load stabilizer able to add damping to all grid modes in the sample power system. Finally, placement and siz ing issues are considered and preliminary observations based on transi ent stability studies are made.