Design of Mexico's Luz y Fuerza distribution automation system

This paper presents the main design aspects of the Information System for the Distribution Network Automation (Sistema de Informacion para la Automatizacion de Redes de Distributcion-SIARED), of Luz y Fuerza del Centro (LYFC), an electric utility serving a retail customer base of around five million in Mexico City and neighboring areas using more than 26500 GWh with a peak load of over 7000 MW. The LYFC transmission network includes two double circuit rings at 400 kV and 230 kV surrounding the metropolitan area, and subtransmission lines at 85 kV serving parts of the metropolitan areas. At present around 50% of the 126 substations have been automated. The remaining 50% are manned. All voltage regulators of the distribution network are located in these substations. There are no switched capacitor banks out of the feeders. The LYFC distribution network includes 930 23/13.2/6 kV feeders with variable lengths in the range of 4 to 140 km. Most of them have normally-open tie switches connecting feeders from the same or from different substation. At 23 kV almost all feeders are interconnected. 13.2 and 6 kV circuits serve rural areas.