Short circuit analysis for integration of 10MW Windfarm in Nigeria at the PCC

A short circuit in a power system can cause very high currents to flow to the fault location. The magnitude of the short circuit current depends on the impedance of system under short circuit conditions. However, to study the effect of windfarm integrated into Power Holding Company of Nigeria (PHCN) which is power bureau of the country, a short circuit calculation was performed studies conducted. The analysis was carried out in two stages, one was using Thevenin equivalent to roughly check unbalance short current from PHCN external source from Kaduna substation at 132/33kV, although this was actually not part of the current studies. The second part was to performed short circuit analysis at network where the windfarm will be connected through 33/11kV level (PCC), which is for this current studies by using computer software tool (DigSILENT powerfactory). This was done to verify the withstands of capacity for the main substation equipment and the new OHLs in comparison with the 3-phase and 1-phase to ground short circuit calculated values of grid studies for the windfarm project. In the network calculation, consideration was made for both maximum and minimum short circuit conditions and it is performed according the IEC 60909 (2001) standards. However, the aim of the analysis was the assessment of the electrical parameters of the WindFarm during and after a three phase short circuit event at the 33 kV Kastina substation because this is the point where the windfarm have to be connected and also the location of the wind generators.