Commonly, a power flow study is done under the assumption that the system is perfectly balance. Therefore the system can be modeled as ordinary single phase system. It is very advantageous considering the computation time and resources that could be saved compared to the complete load flow study for all of the three phase.
Unfortunately, this advantage has its own trade-off. The system unbalance that occurs, especially caused by long unsymmetrical transmission lines, has limitations. If these limitations were violated, the system unbalance could endanger the security of power supplying. In Java-Bali 500 kV interconnection system, there are a lot of long parallel transmission lines which resulting the coupling effects that play a big roll to system unbalance.
Considering its important role in Java-Bali electrical power supplying, the three phase load flow study for Java-Bali 500 kV system is unavoidably needed. In this Final Project, load flow simulation is run on licensed DigSILENT PowerFactory software belongs to ITB. The result of this Final Project can be used to detect, or even to overcome the Java-Bali system unbalance which leads to the improvement of the system performance.