Spare Transformers: Why, how many, and how to compute it all? Purpose of Spare Transformers Spare transformers are kept in stock so that failed units can be replaced relatively quickly.  Absent a spare, most large power transformers have a replacement or repair time of at least 9 – 12 months.  On the transmission system, failure Read more…

The late Rick Gonzalez joined Excel Engineering in 2003 with over 20 years’ experience in electric power system planning and analysis before his passing in 2012. In his previous positions at Northern States Power/Xcel Energy (Minneapolis, MN) and the Western Area Power Administration (Golden, CO), Rick performed short and long-range planning studies for local and regional Read more…

Series Compensation: The Under-Appreciated Transmission Improvement Everyone wants better line and system performance The usefulness of a transmission line is limited by its thermal rating (ampacity), and its series impedance. The ampacity can be increased by installing larger conductor; installing multiple conductors per phase (“bundled conductors”); installing conductor capable of withstanding higher operating temperatures. From this list it Read more…