(Photo courtesy ABB)
ABB has won a large order to supply converter transformers and high-voltage equipment for an 800 kilovolt, ultrahigh-voltage direct current transmission link, owned by the State Grid Corporation of China, in China’s Shaanxi and Hubei provinces, in the North West and Central regions of the country.
The 1,100-kilometer-long power transmission link will transport up to 8,000 MW of electricity, enough to meet the needs of around eight million people in China. The orders were booked in the first and second quarters of 2019.
Converter transformers receive electricity from nearby power stations and increase their voltage to extremely high levels, to transport it over long distances and with minimal losses.
Near to the end consumer, similar transformers will decrease the voltage in order to ensure distribution to the local grid. High-voltage equipment includes breakers, which protect the grid from disruptive faults, and capacitor banks which improve the quality of the electricity supply, thus increasing the product lifespan and helping to reduce losses.
UHVDC uses direct current electricity at extremely high voltages that can have as much as 40 percent lower losses than an equivalent conventional alternating current system. This means far less energy is wasted, more power reaches end users and carbon dioxide (CO2) emissions come down. In this case, savings of up to 1.2 million tons of CO2 emissions per year can be expected.