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Synchronization systems play a vital role in the day-to-day operation of power systems and their restoration after cascading failures. Hence, their resilience to cyberattacks is imperative. In this paper, we demonstrate that a well-planned false data injection attack against the synchronization system of a generator is capable of causing tripping subsequently leading to instability and blackout. We present an analytical framework behind the design and implementation of the proposed cyberattack. Moreover, we derive and discuss the conditions for which a cyberattack interfering with a synchronizing signal can be successful. Effective physical mitigation strategies are then proposed to improve the cyber-resilience of synchronization systems. The proposed cyberattack model and mitigation strategies are verified for a microgrid test system using an OPAL-RT real-time simulator. [ABSTRACT FROM AUTHOR]

Given the strong cyber-physical coupling that exists in power systems today and of the future, false data injection (FDI) attacks have been shown to be feasible in tampering measurement devices by exploiting cyber vulnerabilities to mislead state estimation and related applications. For example, a corrupt generator owner, motivated by financial gain, may manipulate meter readings associated with short-term load forecasts and subsequently misguide the decisions of security constrained economic dispatch (SCED) in ex-ante real-time markets. In this paper, we analyze the feasibility of financially motivated FDI attacks in bi-level programming settings where multi-solution uncertainty of SCED is considered. To deter such attacks, a robust incentive-reduction strategy is proposed that can prevent financially motivated FDI attacks for all the possible load distributions and solutions of SCED requiring a minimal number of protected meters. Simulations for the IEEE 14-bus and IEEE 30-bus test systems demonstrate attack feasibility and performance of the proposed mitigation strategy for SCED in real-time markets. [ABSTRACT FROM AUTHOR]

This work presents a new class of cyber-physical switching attacks that targets power transmission systems. The proposed approach relies on exciting inter-area oscillation modes in a coordinated manner to drive groups of system generators out of step. Our paradigm targets inter-area oscillations by switching a relatively small part (in the order of 2%) of the system load at a (low) frequency that resonates with one of the inter-area oscillation modes observed in the power system. The switching frequency of the targeted mode is chosen through measurement-based analysis of the frequency deviation at a select bus that is observable by the adversary. The inter-area switching attack is implemented as single-load switching and coordinated multi-load switching and is studied with a variety of switching signals. Numerical results show the potential and characteristics of the proposed switching exploitation when applied to the four-machine two-area power system and the Northeast Power Coordinating Council 68-bus system. [ABSTRACT FROM AUTHOR]

A novel framework for the distributed control is proposed in this paper for transient stability of smart power transmission systems in the face of disturbances. The proposed framework seamlessly integrates the traditional governor-based power control with energy storage system (ESS)-based controls. The design objectives also address practical challenges unaccounted for in former work, including limited ESS capacity and availability, and absent, delayed, or corrupt sensor measurements. The IEEE 68-bus test power system is used to demonstrate the merits of the control strategy in enhancing the transient stability of power systems. The results of this paper suggest that integrating different types of control can lead to an enhanced transient stabilization process in the face of different practical limitations. [ABSTRACT FROM AUTHOR]

Security of smart power systems is a sound concern as more cyber elements are added to the power grid. In this paper, we focus on cyber attacks that target data integrity in smart grid systems. We specifically investigate the impact of false data injection (FDI) attacks on distributed transient stability control schemes. As an example, we focus on the parametric feedback linearization (PFL) controller, and we derive closed-form expressions for the errors in rotors’ speed and angle as a result of cyber attacks on data integrity. Furthermore, we investigate adaptive control strategies to eliminate or minimize the impact of FDI attacks on system dynamics. The IEEE 68-bus test power system is used to numerically evaluate the impact of example attacks and to draw valuable insights. [ABSTRACT FROM PUBLISHER]

We propose a framework for the analysis of cyber switching attacks and control-based mitigation in cyber-enabled power systems. Our model of the switching attack is simple, only requiring knowledge of the sign of the local relative rotor speed, which may be estimated. The controller is modeled to be resource constrained, choosing to act only during select intervals of time. We make use of an iterated game-theoretic formulation to describe the interactions of the parties and its effect on system stability. Analytic results indicate the potential of the constrained controller to achieve transient stabilization over time using zero-determinant strategies. Numerical results of the New England 39-bus power system demonstrate the potential for such a controller to increase system resilience during cyber-attacks. [ABSTRACT FROM PUBLISHER]

We present goal-seeking obstacle and collision evasion, an approach to resilient multicast routing for smart grid applications based on principles from robust flocking theory. We assert that analogies exist between the flocking principles of goal seeking, obstacle evasion, collision avoidance and behavioral transitions, and the routing goals of low latency, buffer overflow management, and adaptability in the presence of changing network conditions. Our multicast routing framework employs an underlying dynamical systems model convenient for integration with representations of power system dynamics to produce an overall cyber-physical smart grid description. Through simulations and comparisons with prior art we demonstrate how our approach provides insight on effective multicast routing principles to promote resilience in faulted power systems in the presence of congestion and denial-of-service attacks on communications infrastructure. [ABSTRACT FROM PUBLISHER]

Distributed generators (DGs) are being widely deployed in today’s power grid. These energy sources are highly variable posing practical challenges for deployment and grid management. In this paper, a novel scalable distributed power dispatch strategy is proposed to effectively manage DGs at the distribution substation level, capitalizing on the recent push to cyber-enable power grid operations. We demonstrate how the inherent separability of the power dispatch problem allows the use of dual decomposition that enables every participating DG to locally compute its dispatch strategy based on simple broadcast data by the utility. Results and comparisons indicate that the DGs are able to rapidly converge to an optimal economical dispatch vector with significantly less concentrated computational effort and communication overhead, promoting security and privacy. [ABSTRACT FROM PUBLISHER]

Power systems are on the cusp of a rapid technological, economic, and environmental evolution. Classical problems considered by the power community must naturally adapt to new requirements. Physical and computational constraints within a new landscape must be revisited. In this paper, we focus on the generator scheduling problem, which is also known as the unit commitment problem, in which we incorporate the new constraints of transmission line capacity limits and policy to give a more comprehensive view for planning in a smart grid. Moreover, we consider implications of our formulation to solution complexity. We introduce the concept of matroid theory to model unit commitment as a combinatorial problem and propose distributed solutions to facilitate optimal and correct generator scheduling. We account for communications and computational complexity and demonstrate how although the constrained generator scheduling problem is NP-hard, simpler versions of the problem lead to polynomial-time solutions. [ABSTRACT FROM PUBLISHER]

Generator coherency identification is establishing itself as an important task to aid in the resistance of cascading failures within wide-area power systems and as a necessary preprocessing stage in real-time control for transient stability. Inspired by flocking behavior in nature, we propose a novel multiflock-based technique to identify generator coherence rapidly within a short observation window. Our measurement-based approach transforms generator data from the observation space to an information space, whereby the generator frequencies and phases characterize the movement and dynamics of boids within multiple flocks. Analysis of the boids’ trajectories enables the discrimination of multiple flocks corresponding to coherent generator clusters. We demonstrate the effectiveness of our technique to identify generator coherency rapidly while exhibiting robustness to environmental noise and cyber attack on the 39-bus New England test system and a modified IEEE 118-Bus test system. [ABSTRACT FROM PUBLISHER]

It is well known that information will play an important role in enhancing emerging smart grid system operation. Therefore, questions naturally arise as to when the increased data-dependence may be considered excessive. Two practical considerations emerge: 1) communications and computational overhead, in which redundant and irrelevant information acquisition and use results in heavy computational burden with limited performance return; and 2) increasing risks of power system disruption due to information delay from communication congestion or cyber attack. One strategy to improve smart grid resilience is to determine the appropriate degree of dependence on cyber information to balance performance with overhead and risk. In this paper, we present a hierarchical cyber-physical multiagent model of smart grid system operation based on flocking theory in the context of the transient stability problem. Through this model, we study strategies that harness a selective degree of cyber technology by leveraging physical couplings. Our formulation enables the identification of large-scale distributed control strategies for robust and resilient power grid operation. We demonstrate the potential performance improvements of our findings on the New England 39-bus power system for case studies involving a variety of system faults and communication delays. [ABSTRACT FROM PUBLISHER]

This paper explores distributed smart grid attack strategies to destabilize power system components using variable structure system theory. Here, an opponent is able to remotely control multiple circuit breakers within a power system, say through data corruption or communication network attack, to destabilize target synchronous generators through application of state-dependent breaker switching. In contrast to attack via a single breaker, the multi-switch case provides additional degrees of freedom that can lead to stealthier and wide-scale cascading failures. We provide a dynamical systems context for formulating distributed multi-switch strategies and execute such attacks on the New England 10-generator 39-bus test system. [ABSTRACT FROM PUBLISHER]