3 research outputs found
Physics-Informed Convolutional Autoencoder for Cyber Anomaly Detection in Power Distribution Grids
The growing trend toward the modernization of power distribution systems has
facilitated the installation of advanced measurement units and promotion of the
cyber communication systems. However, these infrastructures are still prone to
stealth cyber attacks. The existing data-driven anomaly detection methods
suffer from a lack of knowledge about the system's physics, lack of
interpretability, and scalability issues hindering their practical applications
in real-world scenarios. To address these concerns, physics-informed neural
networks (PINNs) were introduced. This paper proposes a multivariate
physics-informed convolutional autoencoder (PIConvAE) to detect stealthy
cyber-attacks in power distribution grids. The proposed model integrates the
physical principles into the loss function of the neural network by applying
Kirchhoff's law. Simulations are performed on the modified IEEE 13-bus and
123-bus systems using OpenDSS software to validate the efficacy of the proposed
model for stealth attacks. The numerical results prove the superior performance
of the proposed PIConvAE in three aspects: a) it provides more accurate results
compared to the data-driven ConvAE model, b) it requires less training time to
converge c) the model excels in effectively detecting a wide range of attack
magnitudes making it powerful in detecting stealth attacks
Physics-Informed Machine Learning for Data Anomaly Detection, Classification, Localization, and Mitigation: A Review, Challenges, and Path Forward
Advancements in digital automation for smart grids have led to the
installation of measurement devices like phasor measurement units (PMUs),
micro-PMUs (-PMUs), and smart meters. However, a large amount of data
collected by these devices brings several challenges as control room operators
need to use this data with models to make confident decisions for reliable and
resilient operation of the cyber-power systems. Machine-learning (ML) based
tools can provide a reliable interpretation of the deluge of data obtained from
the field. For the decision-makers to ensure reliable network operation under
all operating conditions, these tools need to identify solutions that are
feasible and satisfy the system constraints, while being efficient,
trustworthy, and interpretable. This resulted in the increasing popularity of
physics-informed machine learning (PIML) approaches, as these methods overcome
challenges that model-based or data-driven ML methods face in silos. This work
aims at the following: a) review existing strategies and techniques for
incorporating underlying physical principles of the power grid into different
types of ML approaches (supervised/semi-supervised learning, unsupervised
learning, and reinforcement learning (RL)); b) explore the existing works on
PIML methods for anomaly detection, classification, localization, and
mitigation in power transmission and distribution systems, c) discuss
improvements in existing methods through consideration of potential challenges
while also addressing the limitations to make them suitable for real-world
applications
Two-Sided Tacit Collusion: Another Step towards the Role of Demand-Side
In the context of agent-based simulation framework of collusion, this paper seeks for two-sided tacit collusion among supply-side and demand-side participants in a constrained network and impacts of this collusion on the market outcomes. Tacit collusion frequently occurs in electricity markets due to strategic behavior of market participants arose from daily repetition of energy auctions. To attain detailed analysis of tacit collusion, state-action-reward-state-action (SARSA) learning algorithm and the standard Boltzmann exploration strategy based on the Q-value are used to model market participants’ behavior. A model is presented that integrates exploration and exploitation into a single framework, with the purpose of tuning exploration in the algorithm. In order to appraise the feasibility of collusion, a theoretical study on a three-node power system with three scenarios is depicted considering three Gencos and two Discos which proves the formation of two-sided tacit collusion between Genco and Disco. Simulation results show different collusive strategies of participants and how parameters of the algorithm impact on simulation outcomes. It is also shown that congestion on transmission line has a significant influence on behavior of market participants