GE’s HVDC Technologies

Line Commutated Converters

Line Commutated Converter is a mature cost effective HVDC technology

based on thyristor power semiconductors, which enables the bulk transfer

of power of up to 8 GW with low losses and inherent DC fault protection.

LCC is available as point to point overhead line and submarine/land cable

and is ideally suited for back to back schemes.

Voltage Source Converters

Voltage Source Converter is a newer technology based on power transistors

with a reduced footprint compared to LCC technology. VSC is an ideal

technology for submarine/land cable interconnection, integrating renewables,

offshore and urban infeed applications. VSC is available as point to point,

back to back, submarine/land cable and offshore schemes. VSC has distinct

technical advantages over the traditional LCC schemes because it creates

an AC waveform that allows the scheme to control real and reactive power

independently and transmit real power into a very weak AC network,

which is not possible with LCC.

HVDC Schemes

Back to Back Scheme

Suitable for frequency changing and asynchronous connections. This

scheme provides fast accurate power flow, limiting the spread of cascading

faults and provides increased system flexibility relative to new generation

requirements. Once interconnected, the two systems’ daily and seasonal

cost differences can also be optimized.

Point to Point Scheme

Commonly used for bulk transfer of power applications utilizing overhead

lines over long distances providing low cost, fully functional, reliable and

environmentally friendly way to transmit power.

Submarine/Land Cable  Scheme

Where the power exchange or transmission crosses water, or an

environmentally sensitive region, cables may be the favored method of

interconnection between the HVDC Converter Stations. HVDC transmission

is particularly attractive and may be the only technically feasible method of

transmitting power using cables.