Improvement of power transfer in an existing power system by means of series and shunt compensation

M.Phil.The Motraco transmission system is a classical case illustrating the increase in power transfer of a network considering the possibility of a voltage collapse. This case study was used in the dissertation to find a techno-economical solution for the Motraco system to increase the power transfer to satisfy an additional load. The Motraco power system is operating close to a voltage collapse at present. A voltage collapse will be experienced if additional load is added at the Maputo substation. The possibility of a voltage collapse can be reduced if the power transfer capability of the Motraco power system is increased. Various technologies can be used to increase the power transfer of the Motraco power system. The technologies used in this study to increase the power transfer were limited to the following: • Adding shunt capacitor banks at critical locations in the network • Adding a series capacitor bank on an existing 400 kV transmission line • Adding an additional 400 kV transmission line • Adding a series capacitor bank on the new 400 kV transmission line The correct use of the combination of the shunt capacitor banks, series capacitor bank and the new transmission line contributes to: • support voltages in the network; • reduce the transmission losses; and • increase the fault levels at the receiving end. The principles used in this dissertation can be used to increase the power transfer limit of any power system with the same characteristics