Flexible AC Transmission Systems (FACTS) is a generic term for a group of technologies that dramatically increase the capacity of existing transmission networks. One of the latest projects is the East Anglia ONE offshore wind farm, which will feature two STATCOM SVC Light® units.
ABB pioneered FACTS technology in the 1950s and remains the market and technology leader. In the past 50 years ABB has executed well over 750 FACTS projects worldwide and has introduced most technology breakthroughs.
FACTS technologies have a small footprint and minimal impact on the environment. Project implementation times are considerably faster and investment costs substantially lower than the alternative of building more transmission lines or new power generation facilities. Where it can take 15 years to negotiate the rights of way and complete a new power line projects, reinforcing an existing line might take only 15 months.
In addition to their primary role of increasing transmission capacity and improving grid control, FACTS technologies are also used to reduce power losses in long-distance power transfer, relieve transmission bottlenecks quickly, minimise the risk of blackouts, and integrate renewable energy sources like wind power into the grid.
In industrial processes, ABB FACTS innovations are widely used in steelmaking to raise productivity and stabilise the effects of the huge electric arc furnaces on the power network and surrounding grid by improving the power quality.
Traditionally, FACTS technologies have been divided into the two categories of series compensation and shunt compensation. All four technologies that make up the two categories – fixed series compensation and thyristor-controlled series compensation in the former, SVC and STATCOM/SVC Light® in the latter – are ABB innovations. ABB has now added a third technology – dynamic energy storage.
Among the more than 750 FACTS projects that ABB has delivered – which is more than 50 percent of the world total – are the following:
Supporting integration of renewables at East Anglia One
When it begins operating in 2020, East Anglia ONE will be the world’s largest offshore wind farm, and will enable ScottishPower Renewables, part of the Iberdrola group, to supply clean energy to nearly 630,000 households.
To avoid voltage fluctuations that arise from intermittent wind power generation at the 714 MW offshore wind power plant, ABB is delivering a grid reliability solution that enhances voltage stability and power quality.
The two ABB static compensator (STATCOM) SVC Light® installations are based on voltage source converter (VSC) technology. They will support voltage stability by instantly and continuously correcting voltage and power factor fluctuations resulting from the inherent intermittency of wind energy generation. In addition, two ABB TrafoStar™ Autotransformers will be incorporated into the system at
Burstall substation.
”ABB’s advanced STATCOM and transformer technologies will not only help stabilize voltage fluctuations and enhance power capacity but also improve the quality and reliability of renewable wind energy supplies to millions of people,” said Patrick Fragman, head of ABB’s Grid Integration business, a part of the company’s Power Grids business. “Renewables and power quality are both key focus areas of our next level strategy and such technology solutions reinforce our position as a partner of choice for enabling a stronger, smarter and greener grid.”
East Anglia ONE is under construction about 43 km off the Suffolk Coast in the North Sea and is the first of several major offshore wind projects that are planned for the UK’s southeastern coast. It will cover a total area of 300 km2 and when it starts generating power in 2020, will become one of the largest offshore wind power plants in the world.
Powering the London Underground
To take its power from the national grid, the London Underground closed its dedicated 180 megawatt (MW) power plant at Lots Road. Special measures had to be taken to limit or even prevent disturbances, such as voltage fluctuations and harmonics, from reaching the public grid. Extensive system studies were undertaken to map sources of distortion and identify the measures needed in order not to exceed the permitted disturbance limits at the points of common coupling.
In 2009, an SVC supplied and installed by ABB was commissioned for the 11 kV feeding grid to work together with five other existing ABB SVCs. Several standalone harmonic filters also operate at critical points of the London Underground 22 kV and 11 kV grid. Space issues and their proximity to underground stations meant that the SVC installations had to be compact and designed to restrict noise and magnetic fields.
Boosting steel mill productivity
ABB has supplied more than 260 SVC and SVC Light® solutions to steel mills all over the world. One of the most well known, is Outokumpu’s Tornio Works steel mill in Finland, where ABB SVC Light® and SVC solutions create a smooth and stable voltage for the huge melting shop, which has a capacity of around one million tons a year. The solutions also reduce harmonics and flicker to prescribed levels, enabling the plant owner to meet the required grid codes.
