17-11-2012, 02:52 PM
HVDC TRANSMISSION
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INTRODUCTION
The conversion of electrical current from AC to DC (rectifier) at the transmitting end, and from DC to AC (inverter) at the receiving end.
Back to back convertors
Back-to-back converters are mainly used
for power transmission between adjacent AC grids which can not be synchronized
Monopolar transmission
For very long distances and in particular
for very long sea cable transmissions, a return path with ground/sea electrodes is the most feasible solution.
Bipolar transmission
A bipolar is a combination of two poles in such a way that a common low voltage return path, if available, will only carry a small unbalance current during normal operation.
Dc Transmission lines
DC transmission lines are part of overall HVDC transmission contract either within a turnkey package or as separately contracted stand-alone item.