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In the realm of power systems, load redistribution attacks (LRAs) involve the manipulation of measurements by attackers, leading operators to make decisions based on falsified estimated loads. Detecting LRAs is a well-explored area, but the critical post-detection phase, which requires operators to understand the attack's nature, remains under-addressed. Our paper introduces a novel probabilistic mechanism based on the Bayesian network model. It excels at not only detecting affected areas but also pinpointing the buses with manipulated loads under LRAs. Our work prioritizes simplicity by offering a straightforward calculation method that doesn't rely on complex tools or extensive system parameters. It also exhibits robustness against measurement noise. Acknowledging the paramount importance of data recovery, we highlight that post-detection measures are essential for minimizing errors in optimal power flow calculations. However, this data recovery is challenging due to the complexity of understanding the attacker's behavior. Our methodology employs kernel density estimation for precise probability density calculations and integrates the Bayesian Markov model to reduce computational complexity. Rigorous testing on the IEEE 118 bus system demonstrates its strong performance in producing consistently satisfactory results.

The fluctuated power output of renewable energy sources brings new challenges to frequency control, especially for islanded microgrids with small spinning reserves. However, energy storage systems and widespread flexible loads can be employed to the frequency regulation thanks to their flexibility of power outputs. This paper investigates the frequency regulation problem for islanded microgrids with distributed heterogeneous energy storage systems (HESS) composed of battery energy storage systems (BESS) and building thermal energy storage systems (BTESS). A distributed event-triggered balanced power sharing strategy considering denial of service (DoS) attacks is designed for frequency regulation by allocating HESS power according to BESS state of charge (SoC), BTESS state of temperature (SoT) and their capacities. The range of control parameters for a stable controller are all provided by Lyapunov analysis. Moreover, the frequency feedback control gain for HESS is derived by using linear quadratic regulator. Simulation results show that the proposed frequency regulation strategy can guarantee the recovery of microgrids frequency and the proportional sharing of HESS power. Besides, SoC and SoT balancing with fewer communications are achieved, even with considering various parameters of HESS, such as capacity, efficiency and with communication link failures as well as DoS attacks.

Parallel virtual synchronous generator (VSG) systems are emerging as an attractive solution for inertia support and frequency stability enhancement of the power grid. However, the dynamic frequency characteristic is more complicated due to the coupled interaction of line impedance, virtual inertia, and damping coefficient in parallel VSG systems. The problems for frequency stability, dynamic performance, and frequency/power oscillation have raised much more attention. In this article, a systematic analysis of the influence of virtual inertia and damping coefficient on the dynamic frequency characteristic among parallel VSG systems was presented, and a quantitative assessment for dynamic frequency performance based on the 2-norm $\boldsymbol {\mathcal{ H}}_{2}$ was proposed. Furthermore, a coordinated control for virtual inertia and damping was proposed to improve frequency stability and achieve a better dynamic performance of parallel VSG systems. The effectiveness and superiority of the proposed method were verified by simulation and experimental results.

In this letter, a novel control scheme is proposed by combining the fractional-order control and the virtual synchronous generator, whereby more degrees of freedom are involved in the controller design. A well-damped power control without oscillations is achieved. At the same time, a significant improvement in the inertial effect is attained. Both theoretical and experimental results have validated the feasibility.

Frequency regulation is important for obtaining higher power supply quality. To our best knowledge, there is no decentralized frequency restoration method for cascaded-type microgrid. This paper proposes a decentralized second frequency control for the cascaded-type microgrid. It only relies on local information to achieve frequency restoration and average power sharing. In addition, the proposed control is suitable for loads with different characteristics. Based on the singularity theory, we provide the control algorithm convergence analysis and control coefficient selection. Finally, the real-time simulation results conducted by RTLAB verify the feasibility of the proposed method.

•Cars and Ships are the main contributors of emissions in the transportation sector.•Electric ships are categorized into hybrid, plug-in hybrid, and all-electric types.•Lack of charging infrastructure is major obstacle in the vast use of electric vehicles.•The major difference between charging station for cars and ships is the power level.•Conductive, wireless, and swapping are the possible ways to charge oboard batteries.•Possible configurations of charging stations based on locality and condition of the grid.

•An economic scheduling model that combines the capital cost of energy storage with the daily operating cost is presented.•A 15 mins scale stochastic power prediction model is presented and based on it, an SMPC strategy is implemented.•An optimal power allocation strategy is presented based on Pontryagin's minimum principle.