Karavia
Customer Story | 2 min read
SVC for dynamic voltage control of a 220 kV transmission system fed by HVDC link
A Static Var Compensator (SVC) rated at 75 Mvar inductive to 75 Mvar capacitive (-75/+75 Mvar) at 220 kV supplied by Hitachi Energy has come on line at the end of 2013 as a Turn-key installation at the Karavia substation of the state utility SNEL (Société Nationale d’Electricité) of the Democratic Republic of Congo. Three MSC (Mechanically Switched Capacitors), each rated at 30 Mvar at 220 kV are part of the installation, as well.
The SVC is part of the rehabilitation of the 220 kV HVAC corridor for power export into the mineral rich Katanga province in the south, holding among other things some of the largest deposits of copper and cobalt in the world. The 220 kV corridor receives large amounts of environmentally friendly hydro power from the Inga Falls on the Congo river over the 1.700 km long Inga-Kolwezi HVDC link. The Karavia 220 kV substation is located approximately 290 km from the Kolwezi converter station at the receiving end of the HVDC link.
The SVC has the following tasks:
- Improve the voltage and angular stability of the 220 kV AC network of Katanga
- Compensate the deficit of reactive power of the grid, otherwise to be imported from neighboring Zambia
- Enhance the first swing stability by maintaining system voltage during large disturbances.
| Main data | |
|---|---|
| System | SVC |
| Commissioning year: | 2013 |
| Controlled voltage | 220 kV |
| SVC rating: | 75 Mvar inductive to 75 Mvar capacitive, continuously variable (-75/+75 Mvar) |
| Control system | Three-phase symmetrical voltage control by means of closed loop voltage regulator |
| Thyristor valve | PCT (Phase Control Thyristor) type, water cooled, indirect light firing |
