July 3, 2012 – ABB says it has successfully developed and tested an 1100-kV ultrahigh-voltage direct current (UHVDC) converter transformer, claiming this breaks the record for the highest DC voltage levels, and facilitating more power to be transmitted efficiently over longer distances.

“This new 1100-kV transformer technology will make it possible to transmit even more electricity efficiently and reliably, at higher voltage levels, across greater distances with minimum losses,” said Bernhard Jucker, head of ABB’s Power Products division.

The Xiangjiaba-Shanghai link, commissioned by ABB, was the world’s first commercial 800-kV UHVDC connection. It has a capacity of 6400 MW and covers a distance of just over 2000 km, making it the longest of its kind in operation. The new 1100-kV converter transformer technology will make it possible to transmit more than 10,000 MW of power across distances as long as 3000 km, claims the company.

Higher voltage levels allow larger amounts of electricity to be transported across very long distances with minimal losses using HVDC technology. Converter transformers play a critical role in HVDC transmission, says ABB, serving as the interface between the DC link and the AC network. Development of the 1100-kV transformer addressed several technology challenges such as the size and scale, electrical insulation (including bushings) and thermal performance parameters.