Bus Split Sensitivity Analysis for Enhanced Security in Power System Operations

Substation circuit breakers play an important role in determining the power grid topology. Misoperations and malicious compromises of circuit breakers can vary the grid topology, and even lead to bus split contingencies. This paper presents a sensitivity analysis framework for modeling the grid-wide impact of bus split events in order to enhance the security of power system operations. Using the popular bus-branch representation, we perform the post-split system analysis via efficiently updating the changes in the system, which turns out to be equivalent to a line outage event followed by an additional pair of power transfer. This equivalent model allows to conveniently incorporate the bus split contingencies into the security-constrained economic dispatch problem to obtain more secure generation dispatch solutions. Numerical studies on a 3-bus system and the IEEE 118-bus case demonstrate the necessity of modeling bus split contingencies and provide the trade-off analysis between generation costs and security enhancement.