Restoration of power to large secondary network distribution systems after a blackout

This paper presents a useful technique to simulate accurately the dynamic behavior of a large secondary distribution network during power restoration. The network load is configured as a set of load blocks distributed along a lumped feeder. Each load block consists of a large group of different appliances and equipment. Each of these components, represented by its dynamic impedance, is modeled at startup by its individual terminal voltage/current relationship; by so doing, there is no need to know the nature or the purpose of the load unit itself. The computer code, originally developed years ago, was recently rewritten and updated for Consolidated Edison of New York. New field surveys were conducted to generate a new database, thus incorporating the extensive technological changes of the recent past. The paper compares computer predictions with field results, past and present, and shows a close correspondence between them.