Enhancing Cyber-Security of Distributed Robust State Estimation: Identification of Data Integrity Attacks in Multi-Operator Power System

State estimation (SE) has a crucial role to play in
the monitoring and control of power grids. Although currently
the SE is typically done in a centralized or hierarchical manner,
distributed SE will become a significant alternative to centralized
and hierarchical approaches in the future smart grids. This
is because the power grids will be increasingly interconnected
in future smart grids and the complexity scale of an interconnection
will render centralized SE computationally formidable.
Performing distributed SE requires leveraging advanced communication
and computation technology. Nevertheless, relying
on communication networks raises its susceptibility to data
integrity attacks, such as false data injection (FDI) attacks. In
this paper, we demonstrate that the attacker who compromises
the communication infrastructure can launch an FDI attack on
distributed SE which could circumvent present robust estimators
and bad data detectors. Afterwards, to effectively defense against
the proposed FDI attack, , two detection methods are proposed
for two different modes of an interconnected power system. A
detector is developed that validates the error of estimates of the
state variables relative to their actual value as an index using a
threshold value for different areas when the network is being run
by an operator. A controlled information dissemination strategy
is utilized to securely notify all areas of each other’s proposed
index when the network is being run by multiple operators.
The proposed algorithms are validated on the IEEE 14-bus test
system.