This paper proposes a distributionally robust optimal operation methodology to coordinate multi-energy interactions and facilitate the emission mitigation for multi-energy systems (MESs) with uncertainty couplings in electricity and carbon markets. A carbon recycling model is proposed to exploit the operational flexibility of multi-energy synergies to enhance economic profits of MES operators under market incentives. Then, a generalized cost model incorporating the lifetime cost of carbon capture and power-to-gas degradation is formulated to provide a quantitative analysis for the coordinated electricity and carbon trading. The co-movements of price fluctuations in electricity and carbon markets are explored through a tailored explainable neural network and uncertainty couplings in the markets are further revealed by a Clayton copula based joint probability distribution (PD) model of price prediction residuals. Moreover, a distributionally robust optimization method is formulated for the optimal coordinated operation of MESs to cope with uncertainties from interrelated fluctuating prices. Numerical studies corroborate the effectiveness and superiority of the proposed methodology in the enhancement of economic and environmental benefits.

In industrial informatics-enabled smart grids, machine learning approaches have exhibited high potential in data-driven electricity theft detection (ETD), whereas none of the existing studies pay sufficient attention to the high costs of manually labeling massive sensing data during learning data preparation. To address this defect, this article develops a cost-effective data-driven ETD approach that significantly reduces the data labeling costs without sacrificing the reliability of ETD. Specifically, the approach is systematically realized via an intelligent deep active learning (DAL) scheme. By seamlessly incorporating convolutional neural network (CNN) learning with Monte Carlo dropout-based Bayesian active query, the DAL scheme efficiently selects the most valuable instances for ETD model training. In this way, the proposed approach is able to derive a reliable CNN-based ETD model with limited labeled learning instances, thus largely reducing the data labeling costs. Experimental test results on an actual ETD dataset provided by the State Grid Corporation of China extensively illustrate the efficacy of the proposed approach.

Eliminating the erroneous state bias from cyberattack is essential to ensure the real-time control and secure operation of the smart grid, especially when cyberattack flourishes in recent years. For this reason, this article,for the first time, proposes a new operating state reconstruction scheme to automatically filter out possible cyberattacks in smart grid. This scheme consists of an attack separation method, a state forecasting algorithm, and a state recovery approach. Based on P-Q decomposition, the attack separation method takes into account the network parameter perturbations and prediction uncertainties to analytically estimate the regular deviation of each state, thereby identifying potential abnormal states. Then, a particle filtering-based state forecasting algorithm is developed to evaluate the original operating level of the detected contaminated states. Finally, we propose a fast bilinear state recovery approach to mitigate the smearing effect of undetected contaminated states due to cyberattacks. The proposed state reconstruction method can not only detect cyberattacks but also realize automatic correction of the erroneous states, thus mitigating the devastating impact of attack on smart grids. The feasibility and effectiveness of our reconstruction scheme are extensively validated on IEEE standard 9-, 14-, 30-, 57- and 118-bus power systems. The obtained results show that the proposed scheme exhibits strong robustness, high stability, and promising performance for automatic attack filtering, indicating a great potential for implementations in deep cyber-penetrated smart grids.

This article proposes a multilateral multienergy trading framework for synergetic hydrogen (H2) and electricity transactions among renewable-dominated hybrid charging stations (HCSs). In this framework, each autonomous HCS with various renewable energy resource (RES) endowment can harvest local renewables for internal green H2and electricity generation to simultaneously meet demands of electric vehicles (EVs) and hydrogen-powered vehicles (HVs) from the transportation network. The surplus electricity/H2production of the HCS is accommodated by external multilateral transactions to increase the additional profit. Besides, each HCS is modeled as a sustainable energy hub, and multiple hubs with multienergy transactions contribute toward a low-carbon energy-transport nexus. A partial differential equation model based on fluid dynamic theory is formed to capture the temporal and spatial dynamics of traffic flows for estimating the EV/HV loads at HCSs. Furthermore, a distributed multilateral pricing algorithm is developed to iteratively derive the optimal prices and quantities for transactive electricity and H2. Comparative studies corroborate the superiority of the proposed methodology on economic merits and RES accommodation.

This article proposes a peer-to-peer transactive multiresource trading framework for multiple multienergy microgrids. In this framework, the interconnected microgrids not only fulfil the multienergy demands of with local hybrid biogas-solar-wind renewables, but also proactively trade their available multienergy and communication resources with each other for delivering secured and high quality of services. The multimicrogrid multienergy and communication trading is an intractable optimization problem because of their inherent strong couplings of multiple resources and independent decision-makings. The original problem is thus formulated as a Nash bargaining problem and further decomposed into the subsequent social multiresource allocation subproblem and payoff allocation subproblem. Furthermore, fully-distributed alternating direction method of multipliers approaches with only limited trading information shared are developed to co-optimize the communication and energy flows while taking into account the local resource-autonomy of heterogeneous microgrids. The proposed methodology is implemented and benchmarked on a three-microgrid system over a 24-h scheduling periods. Numerical results show the superiority of the proposed scheme in system operational economy and resource utilization, and also demonstrate the effectiveness of the proposed distributed approach.

This article proposes an optimal coordinated scheduling of electric vehicles (EVs) for a virtual power plant (VPP) considering communication reliability. Recent advancements on wireless technologies offer flexible communication solutions with wide coverage and low-cost deployment for smart grid. Nevertheless, the imperfect communication may deteriorate the monitoring and controlling performance of distributed energy resources. An interactive approach is presented for combined optimization of dynamic spectrum allocation and EV scheduling in the VPP to coordinate charging/discharging strategies of massive and dispersed EVs. In the proposed approach, a dynamic partitioning model of the multi-user multi-channel cognitive radio is used to cope with the vehicle-to-grid (V2G) communication issue due to variable EV parking behaviors, and a two-stage V2G dispatch scheme is proposed for the wind-solar-EV VPP to maximize its overall daily profit. Furthermore, the effects of packet loss probability on the VPP scheduling performance and battery degradation cost are thoroughly analyzed and investigated. Comparative studies have been implemented to demonstrate the superior performance of the proposed methodology under various imperfect communication conditions.

Understanding potential behaviors of attackers is of paramount importance for improving the cybersecurity of power systems. However, the attack behaviors in existing studies are often modeled statically on a single snapshot, which neglects the reality of a dynamically time-evolving power system. Accordingly, a dynamic cyber-attack model with local network information is proposed to characterize the typical data injection attack with the integration of potential dynamic behaviors of an attacker. The proposed model collaboratively alters the meter measurement in a stealthy way to illegally contaminate the system state, thus posing severe threats to cyber physical power systems. We then develop a novel anomaly detection countermeasure from the perspective of state estimation to effectively recognize the dynamic injection attack. In this countermeasure, an interval state forecasting method is proposed to approximate the possible largest variation bounds of each state variable based on a worst-case analysis considering the forecasting uncertainties of renewable energy sources, electric loads, and network parameter perturbations. In addition, the kernel quantile regression is introduced and implemented to formulate the uncertainties in renewable energy and electric load forecast as a series of confidence intervals. When any state variable falls outside its preforecasted intervals, the proposed countermeasure detects the anomaly and sets an alarm condition indicating the possibility of data contamination. Finally, the results from our extensive studies on several IEEE standard test systems have been presented to demonstrate the feasibility of the dynamic attack and the effectiveness of the detection countermeasure.

This paper proposes a distributed multienergy management framework for the coordinated operation of interconnected biogas-solar-wind microgrids. In this framework, each microgrid not only schedules its local hybrid biogas-solar-wind renewables for coupled multicarrier energy supplies based on the concept of energy hub but also exchanges energy with interconnected microgrids and via the transactive market. The multimicrogrid scheduling is a challenging optimization problem due to its severe constraints and strong couplings. A multimicrogrid multienergy coupling matrix is thus formulated to model and exploit the inherent biogas-solar-wind energy couplings among electricity, gas, and heat flows. Furthermore, a distributed stochastic optimal scheduling scheme with minimum information exchange overhead is proposed to dynamically optimize energy conversion and storage devices in the multimicrogrid system. The proposed method has been fully tested and benchmarked on the different scaled multimicrogrid system over a 24-h scheduling horizon. Comparative results demonstrated that the proposed approach can reduce the system operating cost and enhance the system energy-efficiency, and also confirm its scalability in solving large-scale multimicrogrid problems.

Due to the aging of electric infrastructures, conventional power grid is being modernized toward smart grid that enables two-way communications between consumer and utility, and thus more vulnerable to cyber-attacks. However, due to the attacking cost, the attack strategy may vary a lot from one operation scenario to another from the perspective of adversary, which is not considered in previous studies. Therefore, in this paper, scenario-based two-stage sparse cyber-attack models for smart grid with complete and incomplete network information are proposed. Then, in order to effectively detect the established cyber-attacks, an interval state estimation-based defense mechanism is developed innovatively. In this mechanism, the lower and upper bounds of each state variable are modeled as a dual optimization problem that aims to maximize the variation intervals of the system variable. At last, a typical deep learning, i.e., stacked auto-encoder, is designed to properly extract the nonlinear and nonstationary features in electric load data. These features are then applied to improve the accuracy for electric load forecasting, resulting in a more narrow width of state variables. The uncertainty with respect to forecasting errors is modeled as a parametric Gaussian distribution. The validation of the proposed cyber-attack models and defense mechanism have been demonstrated via comprehensive tests on various IEEE benchmarks.

Multiobjective optimal reactive power dispatch (MORD) is a highly constrained nonlinear nondifferential multimodal Pareto optimization problem with a mixture of continuous and discrete variables. This paper presents a novel strength Pareto multigroup search optimizer (SPMGSO) for solving this challenging problem. In the proposed algorithm, a number of enhancement mechanisms, such as ring-migration synergistic cooperation, crowding entropy constraint treatment, and chaotic logistic dispersion, were developed to effectively strengthen the diversity and distribution of the resulting nondominated front (NDF). The final best compromise solution is then extracted from the NDF using a hierarchical clustering and an equilibria-based multicriteria decision-making scheme. In addition, the multicore processing was introduced to parallelize the multigroup search so as to greatly improve the execution speed of the algorithm. Computational studies on the benchmark IEEE 30-bus and 162-bus power systems have confirmed the superior performance and improvement of the proposed algorithm for solving this Pareto problem, and demonstrated its applicability and capability to cope with the high-dimensional MORD problems with multiple operational objectives.