Carnegie Mellon Electricity Industry Center

2004-05 Seminars

Power System Restoration after Failures

Mike Adibi
IRD, Inc.

Abstract
Given, that blackouts are likely to occur, one might ask what are being done to reduce their impact, i.e., their extent, intensity and duration? Immediately after the initial event, the power system frequency rise and decay are arrested automatically by load rejection, load shedding, isolation scheme and controlled islanding. The success rate of these automatic schemes has been over 50%! The challenge has been to coordinate the control and protective systems between the generating plants and the electrical system which have up to two orders of magnitude response differences.

In the subsequent restoration phase, plant operators in coordination with system operators attempt to manually maintain a balance between load and generation by using the available initial sources of power and supplying the critical loads by priority. The duration of these manual procedures has invariably taken much longer than the equipment limitations. In view of the industry's breakup, the concern is that the power plants - power system manual coordination may no longer receive the due attention, resulting in a greater blackout impact.

It is concluded that research and development efforts in the automatic coordination of power plants - power system is more expedient and in near term more advantageous resulting in a reduced blackout impact.

Slides