19-21 June 200 Delivering Power in West AfricaOne of the most important infrastructure projects in Africa is currently under way to transfer power from the Manantali Hydro Dam to Mali and Senegal with a branch off to Mauretania in West Africa. ABB, in consortium with Norelec of France, and SOGEM, Société de Gestion de l'Energie de Manantali of Mali, who is responsible for generation and transmission of electrical energy in the three countries - Mali, Senegal and Mauritania, have been awarded a contract to supply an 800 km long series compensated transmission line interconnecting Mali-Senegal. Norelec will provide over 800 km of overhead transmission lines, ABB's scope of supply are seven 225 kV power transformers, HV-equipment for five sub-stations and technically demanding series compensation. ABB Power Systems' part of the total project is to deliver five 225 kV series capacitor banks, 22.3 Mvar each, at substations Dagana and Matam in Senegal, and Kayes in Mali. Lines over 300 km are classified as long lines and they constitute significant series impedance which impedes power flow. Long lines can also cause high system voltages during light load conditions because of the interaction between lines series inductance and charging currents associated with shunt admittance. This in turn can cause system stability problems. The series capacitors in this project compensate for the series impedance of the transmission line. They will optimize power flow, increase power transfer capability and reduce transmission losses. This important electrical link will enter service in April 2002. |
