Application of fault current limitation techniques in a transmission system

The paper describes the applications of fault current limiting techniques to Oman electricity transmission system to overcome high short-circuit currents in some parts of the grid. These include splitting busbars at selected grid stations, regrouping generators at power stations, opening transmission lines at critical points, and introducing fault current limiters at strategic places in the network. Computer simulation results, using DIgSILENT software package, are presented to show the effectiveness of these techniques in reducing the short-circuit currents at critical busbars. The results have shown that the calculated short-circuit currents can be reduced to be within the fault level capacity of the existing switchgears. Splitting busbars and regrouping generators are considered as short-term temporary solutions with no cost. Practical implementation of this technique at Rusail power plant is described. Employing fault current limiting reactors is considered as a long-term permanent solution.