HVDC LCC, called HVDC Classic, is primarily used for connecting remote generation over long distances, Grid interconnection and DC links in AC grid, overland or subsea, where conventional AC methods cannot be used.
Today there are more than 170 HVDC LCC installations in all parts of the world. The HVDC Classic transmission typically has a power rating of more than 100 megawatts (MW) and many are in the 1000 – 12000 MW range.
With HVDC Classic from Hitachi ABB Power Grids, it is possible to transmit power in both directions and to support existing AC grids in order to increase robustness, controllability and stability of the grid.
What is HVDC Classic?
Energy systems around the world are becoming increasingly decarbonized, distributed – and demanding. That’s why HVDC Classic steps into the limelight: It provides transmission system operators with an exceptionally economical and efficient opportunity to supply load centers. Such a bulk power transmission system delivers the required amounts of power, stabilizes heavily strained AC grids, and establishes an interconnected power system across regions and countries. The proven technology behind HVDC Classic, which is based on line-commutated current-sourced converters (LCC), has been continuously improved over the years. Today, HVDC Classic systems from Siemens transmit up to 10 GW of power, this way providing the secure, stable, and profitable backbone for today’s increasingly complex transmission systems as well as for grid interconnection and for UHVDC transmission.
Today, many transmission system operators are required to provide additional grid capacity and improve grid performance and resilience. They’re also expected to take an active part in the establishment of interconnected power systems and contribute to CO2 emissions reduction through the integration of power from renewable sources. HVDC Classic provides the opportunity to tackle these challenges successfully.
- Transmission capacity of more than 10 GW per bipolar system at a voltage level of ±800 kV (± 1100 kV)
- Highly efficient converter stations with losses of approximately 0.7% of rated power
- Significantly lower costs for rights of way and overhead lines than with comparable AC solutions
- Possibility to establish a bulk power transmission system bridging more than 2,000 km for infrastructure improvements
- Compensation of dynamic AC system disturbances thanks to high overload ratings
- Grid interconnection capability to support large grids and stabilize parallel AC systems