Protection strategies against cascading failure for Singapore transmission grid

The vulnerability of power grid is a key issue with large blackouts, causing power supply to be halted for millions. With a special touch on power grid of Singapore, this study aims to provide practical and effective protection schemes to enhance grid robustness against cascading failure caused by intentional or unintentional attack. Power grid distinguishes itself from other networks like traffic and Internet with hierarchic structure and power flow restriction. To generate realistic results, we adopted real-world power flow convention to Wang´s cascading model in modeling power network. The simulation results led to the discovery of intrinsic vulnerability introduced by grid structure and the correlation between grid robustness and power demand. We proposed and verified 3 protection schemes, namely Cascaded Load Cut-off (CLC), Cascaded Load Overflow (CLO) and Cascaded Load Spread (CLS), among which CLS was proven the most effective to enhance the grid robustness against various attacks on 230kV and 66kV grid.