APPLICATIONS OF HIGH VOLTAGE DC TRANSMISSION

1) CONNECTING REMOTE GENERATION

Some energy sources, such as hydro and solar power, are often located hundreds or thousands kilometers away from the load centers. HVDC will reliably deliver electricity generated from mountain tops, deserts and seas across vast distances with low losses.

2) INTERCONNECTING GRIDS

Connecting AC grids is done for stabilization purposes and to allow energy trading. During some specific circumstances, the connection has to be done using HVDC, for example when the grids have different frequencies or when the connection has to go long distances over water and AC cables cannot be used because of the high losses.

3) CONNECTING OFFSHORE WIND

Wind parks are often placed far out at sea, because the wind conditions are more advantageous there. If the distance to the grid on land exceeds a certain stretch, the only possible solution is HVDC - due to the technology’s low losses.

4) POWER FROM SHORE

Traditionally, oil and gas platforms use local generation to supply the electricity needed to run the drilling equipment and for the daily need of often hundreds of persons working on the platform. If the power is instead supplied from shore, via an HVDC link, costs go down, emissions are lower and the working conditions on the platform are improved.

5) DC LINKS IN AC GRIDS

HVDC links within an AC grid can be successfully utilized to strengthen the entire transmission grid, especially under demanding load conditions and during system disturbances. Transmission capacity will improve and bottlenecks be dissolved.

6) CITY-CENTER INFEED

HVDC systems are ideal for feeding electricity into densely populated urban centers. Because it is possible to use land cables, the transmission is invisible, thus avoiding the opposition and uncertain approval of overhead lines.

7) CONNECTING REMOTE LOADS

Islands and remotely located mines often have the disadvantage of a weak surrounding AC grid. Feeding power into the grid with an HVDC link, improves the stability and even prevents black-outs.

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Monday, 04 December, 2017

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