The Future of High Power Electronics in Transmission and Distribution Power Systems

Although the term "Power Electronics" covers a very wide spectrum of power ratings and applications (from Watts to Gigawatts), Power Electronics applications for the Transmission and Distribution (T&D) market tend to be amongst the very highest in terms of voltage and power rating. Moreover, these applications are part of a very rapidly growing market and one that is closely linked with the emerging field of "Smart Grids". Some T&D applications of Power Electronics, such as High Voltage Direct Current (HVDC) have been available for many decades, yet are currently enjoying an unprecedented period of market growth and rapid technical development. Voltage-Sourced Converter technologies (VSC) now sit alongside conventional Current-Sourced (Line Commutated) HVDC solutions and are opening up new market segments. Other "Flexible AC Transmission" (FACTS) systems, such as the STATCOM, are also available in the Transmission (HV) market and are starting to penetrate the Distribution (MV and LV) markets. AREVA T&D was a pioneer in the design of transmission STATCOMs, and built the world's first commercial STATCOM project using its "chain link" technology. MV applications of power electronics are driven mainly by the challenges imposed by distributed generation such as wind energy. The STATCOM can be equipped with battery energy storage to smooth out short-term variability of power generation, or even to connect to other STATCOMs via a DC cable network, creating an "MVDC" grid. With a new generation of MV or HV DC-DC converters, it is even possible that one day DC will once again become the preferred medium for power transmission, just as it was promoted by Thomas Edison in the 1880s.