communication and information networks. For example,
results presented in [2] show that an increase in time delay can
cause degradation of frequency control using decentralized
intelligent loads. Furthermore, too much latency can lead to
system instability. As a result, the present state and dynamics
of communication networks can be a critical contingency for
current and future smart grid applications. The objective of
this work is to develop a modeling methodology for analyzing
smart grids, control techniques, and identifying important
contingencies within cyber and physical elements of the
system specifically for wide area control applications. These
contingencies could be malicious, for example a cyber or
physical attack on a network, or non-malicious. A critical
component for modeling smart grids is modeling the
interdependencies and interactions between the cyber and
physical components.
Vulnerability analysis of power systems and information
networks is a continuing field of research [3-5]. The focus of
many research efforts have been placed on large cascading
failures due to impacts of such disruptions. Historically, much
research has focused on either the power grid or information
networks [6, 7]. Recently the interdependencies of the two
infrastructures been studied [3, 8, 9]. The current state-of-theart
techniques rely on qualitative analysis of the systems and
interdependencies [5] and, as a result, develop approximate
results and estimations of the real interdependencies of the two
systems. Some work is moving towards a quantitative
approach more suitable for analyzing smart grid applications
and contingencies [10]. The approach described in this paper
is to develop a unified quantitative methodology of modeling
both the cyber and physical components of the system, and the
interdependencies between the two. More specifically the
focus is on a unified cyber/physical system model suitable for
simulation and analysis of the following:
• Physical contingencies in HV transmission
network/bulk power generation and sensors
• Cyber contingencies in smart grid components
related to HV transmission/bulk Generation
• Decentralized local and wide area control
• Centralized wide area control
Some specific examples of wide area control techniques of
interest are voltage control, frequency control, and small
signal stability control for inter-area modes. Of particular
interest is how advanced wide area control techniques are
susceptible to contingencies of physical and/or cyber
components.