Understanding the Cascading Failures in Indonesian Power Grids with Complex Network Theory

On 18 August 2005, one of the biggest power outages in world history occurred in Java-Bali power grids system in Indonesia which impacts on almost 100 billion people for about 3 hours. A failure in the 500 kV transmission line between Saguling-Cibinong has caused the transmission line to break down resulting in the power grid network to dissolve into two separate networks, which in the end led to cascading failure along the whole grid. Power grid topology plays an important role in determining system behavior when one or more connections failed and impacting the whole network. In the worst case, cascading failure might take place which disturbs the whole networks. The objectives of the paper are to understand how a cascading failure incident takes place in power grids and find the correlation between key parameters using complex network theory to improve power grids robustness. The paper concentrate on an edge-based attack model as it has a resemblance with the Java-Bali power outages incident in 2005. The result indicates characteristics of small-world network from Java-Bali power grid, with different tunable parameters and load ratios, have an impact on network cascading failure likelihood.