Fewer losses: Controls help high-voltage projects in China, Nambia

High-voltage automation technologies are helping projects in China and Nambia, with help from ABB. ABB won orders worth $440 million from the State Grid Corporation of China and other partners to provide new ultrahigh-voltage technology for the world’s longest power transmission link, at more than double the highest power rating at present. In separate, related news, ABB won an order worth $180 million from Namibian national power utility, NamPower, adding to grid stability in that region.

By Control Engineering Staff December 28, 2007

Zurich, Switzerland – High-voltage automation technologies are helping projects in China and Nambia, with help from

ABB

. ABB won orders worth $440 million from the State Grid Corporation of China and other partners to provide new ultrahigh-voltage technology for the world’s longest power transmission link, at more than double the highest power rating at present. In separate, related news, ABB won an order worth $180 million from Namibian national power utility, NamPower, adding to grid stability in that region.

The power superhighway running 2,000 kilometers (1,240 miles) from western China to the industrialized coastal area in the east, will have a capacity of 6,400 MW, enough to meet the needs of approximately 31 million people, based on average consumption per capita. The link from Xiangjiaba hydropower plant to Shanghai is scheduled for completion in 2011.

An ultrahigh-voltage direct current (UHVDC) link comprises two substations and a power transmission system using breakthrough technology to transmit electricity at ultrahigh voltage (800 kV), to minimize the amount of power lost in transmission. Increasing the voltage level of electrical transmission creates considerable advantages for the environment, including lower electricity losses and the use of less land compared to traditional overhead lines. UHVDC is suitable for vast countries like China, where centers that need power may be located far from power sources.

This project represents breakthroughs in electrical power transmission: The 6,400 MW power rating is more than double the most powerful rating in operation. At 2,000 km, the transmission line will be the longest in the world. Transmission losses will be less than 7%, less than the losses from conventional 500 kV high-voltage direct current (HVDC) transmission schemes. Savings from using UHVDC compared with HVDC are equivalent to the annual power consumption of more than 900,000 people in China, ABB noted.

“Ultrahigh voltage transmission is a vital new technology for the efficient use of hydropower generated in remote areas,” said Peter Leupp, head of ABB’s Power Systems division. “ABB technology, which plays an essential role in this project, can support the economic development of some of the world’s most populous regions, while lowering environmental impact.”

In related news, a Namibian national power utility, NamPower, will connect two parts of the country’s power grid and strengthen electricity networks in southern Africa, with help from an ABB $180 million ABB contract. NamPower is building a 350 kV, 300 MW transmission link between the northeastern Caprivi region and the power network in central Namibia. The link will interconnect electricity networks of Namibia, Zambia, Zimbabwe, the Democratic Republic of Congo, Mozambique, and South Africa to create an alternative route for power imports and exports to and from neighboring countries. The design allows for an extension to 600 MW. The link will use ABB’s environmentally friendly HVDC Light system, a transmission technology that will stabilize the two weak networks and increase grid reliability in the region.

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