Caprivi Link HVDC Interconnector: Site selection, geophysical investigations, interference impacts and design of the earth electrodes
The Caprivi Link HVDC Scheme in Namibia, connecting the Zambezi 330 kV substation close to Katima Mulilo in the Caprivi Strip to the Gerus 400 kV substation in the centre of Namibia has been designed for both metallic return and earth return when operating in monopolar mode. A future bipole extension is planned. The paper gives an overview of the scheme, the various operating configurations and the advantages of using earth return in monopolar mode. The paper outlines the approach followed and methodology utilised to select suitable sites for earth electrodes. The criteria considered important for the selection of earth electrode sites are described. An overview is provided of the geophysical investigations and studies undertaken to select suitable sites for earth electrodes. Interference investigations carried out to determine the possible effects of earth electrode operation are described. The design criteria and the preliminary design of the earth electrodes are described. Keywords: Earth electrodes, Site selection, Geophysical investigations, Interference investigations, Design criteria.
|Caprivi Link HVDC Interconnector_2010.pdf