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he microgrid (MG) is a complicated cyber-physical system that operates based on interactions between physical processes and computational components, which make it vulnerable to varied cyber-attacks. In this article, the impact of data integrity attack (DIA) has been considered, as one of the most dangerous cyber threats to MGs, on the steady-state operation of hybrid microgrids (HMGs). Additionally, a novel method based on the sequential hypothesis testing approach is proposed to detect DIA on the renewable energy sources’ metering infrastructure and improve the data security within the HMGs. The proposed method generates a binary sample, which is used to compute a test statistic that is further used against two thresholds to decide among three alternatives. The performance of the suggested method is examined using an IEEE standard test system. The results illustrated the acceptable performance of the proposed methodology in detection of DIAs. In addition, to evaluate the effect of DIA on the operation of the HMGs, DIAs with different severities are launched on the measured power generation of renewable energy resources like wind turbines. The results showed that a successful DIA on renewable units can severely affect the operation of electric grids and cause serious damage. [ABSTRACT FROM AUTHOR]

Iran is one of the most potent energy exporters and fastest‐growing energy consumers in the world. Its large amount of energy exported can directly impact the economy of importer countries. Iran's energy matrix mostly consists of hydrocarbons, while the remaining portion is compounded by a blend of biofuels, hydropower, wind, solar, and other renewable sources. Even though the country has an excellent potential to reach a large amount of renewable power, it is most likely that Iran will deal with a shortage in its electricity segment during the upcoming years. Besides wind and solar energy, bioenergy appears to be a good alternative for enhancing the country's energy matrix and transit Iran's energy consumption pattern from a high‐level usage of hydrocarbons to a more renewable scenario. Therefore, in the present paper, the role of Iran in global energy production is discussed, and its potential for renewable energy generation is described. The review presents a vast set of data related to environmental, infrastructural, economic, and social aspects to clarify the potential and benefits of Iran's transition to a more renewable energy matrix. The investigations revealed the country's extremely favourable conditions to use bioenergy resources as a key solution to avoiding future energy crises, besides improving quality of life. The context can help researchers, power suppliers, and energy consumers know how renewable energies, especially bioenergy, can modify the energy matrix of a country rich in hydrocarbon resources. [ABSTRACT FROM AUTHOR]

Advances in technology and population growth are two factors responsible for increasing electricity consumption, which directly increases the production of electrical energy. Additionally, due to environmental, technical and economic constraints, it is challenging to meet demand at certain hours, such as peak hours. Therefore, it is necessary to manage network consumption to modify the peak load and tackle power system constraints. One way to achieve this goal is to use a demand response program. The home energy management system (HEMS), based on advanced internet of things (IoT) technology, has attracted the special attention of engineers in the smart grid (SG) field and has the tasks of demand-side management (DSM) and helping to control equality between demand and electricity supply. The main performance of the HEMS is based on the optimal scheduling of home appliances because it manages power consumption by automatically controlling loads and transferring them from peak hours to off-peak hours. This paper presents a multi-objective version of a newly introduced metaheuristic called the bald eagle search optimization algorithm (BESOA) to discover the optimal scheduling of home appliances. Furthermore, the HEMS architecture is programmed based on MATLAB and ThingSpeak modules. The HEMS uses the BESOA algorithm to find the optimal schedule pattern to reduce daily electricity costs, reduce the PAR, and increase user comfort. The results show the suggested system's ability to obtain optimal home energy management, decreasing the energy cost, microgrid emission cost, and PAR (peak to average ratio). [ABSTRACT FROM AUTHOR]

The integration of various types of renewable energy sources and storage systems into power system increases the complexity of the conventional power system, necessitating a comprehensive optimal power flow (OPF) analysis with multiple and/or competing objectives. From this viewpoint, the paper proposes optimal utilization of different power system entities, by solving the OPF problem using the heuristic particle swarm optimization technique. The proposed methodology optimizes the power flow of a complex, nonlinear hybrid power system to fulfill several objectives, viz. line loss minimization, cost minimization and profit maximization under varying environmental conditions and system attributes. A modified IEEE system replacing conventional sources with renewables and storage system is considered for study. Results corroborate the effectiveness of the strategy. [ABSTRACT FROM AUTHOR]

Generation of renewable energy sources and their interfacing to the main system has turn out to be most fascinating challenge. Renewable energy generation requires stable and reliable incorporation of energy to the low or medium voltage networks. This paper presents the microgrid modeling as an alternative and feasible power supply for Institute of Technology, Hawassa University, Ethiopia. This microgrid consists of a 60 kW photo voltaic (PV) and a 20 kW wind turbine (WT) system; that is linked to the electrical distribution system of the campus by a 3-phase pulse width modulation scheme based voltage source inverters (VSI) and supplying power to the university buildings. The main challenge in this work is related to the interconnection of microgrid with utility grid, using 3-phase VSI controller. The PV and WT of the microgrid are controlled in active and reactive power (PQ) control mode during grid connected operation and in voltage/frequency (V/F) control mode, when the microgrid is switched to the stand-alone operation. To demonstrate the feasibility of proposed microgrid model, MATLAB/Simulink software has been employed. The performance of fully functioning microgrid is analyzed and simulated for a number of operating conditions. Simulation results supported the usefulness of developed microgrid in both mode of operation. [ABSTRACT FROM AUTHOR]

Reliable electrical distribution system is the primary requirement of smart grid. Further, with the integration of intermittent renewable energy sources (RESs), reliability assessment is very vital. Various deterministic and probabilistic methods are utilized to assess the reliability of distribution system. This review study is about distribution system reliability assessment (DSRA) with and without renewable energy generation technologies such as micro grid, distributed generation, solar and wind. For that purpose, DSRA methods such as Monte Carlo simulation (MCS) and other DSRA methods are discussed. The distribution system reliability is considered by using the renewable energy generation techniques. The stochastic features of the parameters in the designing process defined the type of MCS simulation technique. These techniques are utilized to provide reliability assessment of compact system due to huge computational time associated with them. It can be restricted by restricting number of lumped equipments for a given renewable energy source. Further, numerous states can also be used to describe the arbitrariness in the renewable energy generation, because of the stochastic behavior of the resources and the mechanical degradation of the system. [ABSTRACT FROM AUTHOR]

• New types of equivalent techniques under the penetration of inverter-based resources (IBRs) is reviewed. • A thorough review of power system reduction techniques, with the inclusion of the new emerging components in modern power systems such as reducing the models of generators driven by renewable energy resources, microgrids, and active networks. • The authors are working on new techniques for the size reduction of the power system in the context of high penetration of IBRs to the grid. Examples of data driven techniques for enhancing the power system size reduction techniques are presented. It is well known that dynamic studies of large power systems are essential, and they are even more critical for interconnected systems that host high level of renewable energy systems which are interfaced with the grid through power electronic inverters. As power system stability studies need to be done frequently in large systems to adjust various control parameters, it is required to reduce the computational time of each study while maintaining the accuracy of studies. As such, it is desired that some preliminary studies be performed on simplified reduced size models before conducting final studies with full models. Creating reduced-size dynamic models is usually required for three applications: planning studies, online dynamic security assessment, and real-time simulators. As such, there is a need to review the conventional techniques of reducing the dynamic models of power networks and perform new research in developing techniques of incorporating aggregated dynamic models of renewable energy systems into the network reduction methods. The main contribution of this paper, in addition to a thorough review of power system reduction techniques, is the inclusion of new emerging components in modern power systems such as size reduction of Inverter-Based Generator models. [Display omitted] [ABSTRACT FROM AUTHOR]

• The following are the research highlights of the proposed work. • Analyzed LVRT capability of DFIG based WT during symmetrical grid fault. • Enhanced LVRT capability of DFIG based WT by incorporating of crowbar resistance • Comparative analysis between the existing and developed crowbar protection is presented • Comparative analysis under steady-state and symmetrical fault conditions at RSC and GSC is presented. Doubly-fed induction generators (DFIGs)-based wind turbine (WT) are the major sources of renewable energy generation around the world. The low voltage ride-through (LVRT) capability of such sources must be improved to keep them connected with the grid during faults. Due to its sensitivity to the grid disturbances, sober arrangements should be made to keep DFIG connect to the grid. Therefore, this paper implements the crowbar resistance protection scheme on the practical 153MW ADAMA-II wind farm, situated in Ethiopia, for enhancing the LVRT of WT. The dynamic performance of the DFIG-based WT incorporated with the crowbar resistance is analyzed and compared under steady-state and symmetrical grid disturbances. To show the effectiveness of the proposed scheme, the dynamic performance is analyzed and compared with the existing capacitor bank system by observing various parameters. For modeling and simulation purposes, MATLAB/Simulink software is utilized in this research study. The results verify the superiority of the proposed LVRT capability in practice. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Over the past decade, energy storage in renewable energy-dominated systems has received increasing interest. Effective energy storage has the potential to enhance the global hosting capacity of renewable energy in power systems, accelerate the global energy transition, and reduce our reliance on fossil fuel-based generation. Pumped hydro storage (PHS) is the most common storage technology due to its high maturity, reliability, and effective contribution to the integration of renewables into power systems. Accordingly, it is essential to achieve the optimal operation of energy systems combined with PHS. Therefore, this paper comprehensively reviews recent efforts toward the optimal operation of PHS-based energy systems (PHS-BES), considering the diversified energy sources, configurations, grid connectivity, and research directions. The evaluation criteria for the optimal operation of these systems are mathematically addressed and discussed. Moreover, methods of solving the studied problem are categorized and several improvements are suggested. It is observed that more flexible energy policies are urgently needed to encourage new investments in PHS, and the existing environmental and social criteria require further research. Moreover, the hybridization of PHS with other storage devices should be further investigated, and the development of robust hybrid methods for solving the optimal operation of PHS-BES, especially for real-time applications, is highly promising. Based on an in-depth analysis, this paper provides a compendium of real-world research and industry-oriented challenges, and presents future research and industry trends for the optimal operation of PHS-BES. • The latest studies on the optimal operation of PHS-BES are reviewed. • PHS-BES are categorized based on the number and type of integrated energy sources. • The evaluation criteria and solving methods for the optimal operation of PHS-BES are discussed. • A compendium of real-world research and challenges is presented. • Future research on PHS-BES is concluded. [ABSTRACT FROM AUTHOR]