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Issues related to stable microgrid (MG) operation often pose challenges for engineers and researchers, including energy management, power quality maintenance, and the effect of perturbations. Therefore, continuous measurement and monitoring of the system's stability level require special attention. Thus, motivated and focused on addressing these issues, this paper presents a novel decision-making methodology for determining the MG stability index (MGSI) to comprehensively measure the MG stability level. The proposed index is based on continuously measuring fundamental MG parameters, including voltage, frequency, battery state of charge (SOC), and total harmonic distortion. The influence of these parameters on system stability is considered using 256 rules in a Mamdani-based fuzzy inference system. The proposed methodology is evaluated through seven case studies considering different modes of MG operation, types of loads, and availability of power sources and simulated using MATLAB Simulink software. The results demonstrate variations in MGSI for different investigated scenarios, such that a grid-connected MG system with high renewable output and high battery SOC, along with critical/noncritical load, exhibits the best MGSI compared to an islanded MG system with low renewable output, low battery SOC, and an inductive load that shows least MGSI. Additionally, to demonstrate the credibility of the fuzzy-based controller in complex decision-making, a comparative analysis is performed with the analytic hierarchy process under the multi-criteria decision-making technique. The paper also includes sensitivity analysis that reflects the system's sensitivity to different input sources and robustness analysis of the controller. [ABSTRACT FROM AUTHOR]

Rural and remote area electrification is of grave concern around the globe. Therefore, well-planned and cost-effective microgrids integrating renewable energy sources are emerging as effective solutions. However, the microgrid's stable operation and its future deployment is affected by the perturbations caused due to uncertainity in renewable sources, dependency on the battery state of charge, and load variation. So, considering the possible concerns affecting the planning and development of a microgrid for any given region, this paper proposes a comprehensive performance assessment of the hybrid residential microgrid based on a load model of Kibber village in Himachal Pradesh, India. The proposed approach is divided into three parts for the best planning of microgrids. Firstly, the MATLAB–Simulink software technically analyzes the system performance under perturbations considering the available renewable sources. Secondly, an economic analysis using HOMER Pro software is done to examine the cost-effectiveness of the proposed microgrid model through the simulation of electrical loads for Kibber village, considering the available renewable sources. Lastly, a real-time analysis of the proposed prototype of programmable logic controller-based hardware test bench has been developed, aiming for future regional microgrid deployment. System voltage, frequency, power shared, percentage of load met, energy cost, available renewable energy resource, etc. have been considered for validating the proposed controller. The proposed comprehensive assessment of the microgrid model is reproducible with necessary modifications for any geographical location. It will be helpful for its future deployment aiming at rural and remote electrification. [ABSTRACT FROM AUTHOR]

In recent times, with the increase in the penetration of various renewable energy sources (RESs) into power systems, the complications related to the stability issues have increased. The main contribution of this paper is an in‐depth analysis of research in microgrid based on small‐signal, transient, and voltage stability. The small‐signal stability has been discussed based on uncertain load, limitation in power generation capacity, and nature of sluggish feedback observed in few microgrid systems. Instability caused by a transient phenomenon in microgrid has been thoroughly analyzed for losses in distributed energy resources (DERs), islanding and transition modes of operation, load shedding, and faults causing instability. The voltage fluctuations are duly considered in the perspective of load shedding, type of loads, power unbalancing, and different types of faults in microgrid systems. The existing controllers have been compared based on steady‐state error, response time, and robustness etc. The voltage, frequency, and active/reactive power control are analyzed based on centralized, decentralized, hierarchal/distributed control schemes aiming stabilization of microgrid systems. Finally, stability improvement features have been explored in detail, finding the implementation of microgrid stabilizers, energy storage devices, FACTS devices, load balancing, resource forecasting including the adaptive controller. Hence, the uniqueness of this paper can be considered as a state‐of‐the‐art review of the abovementioned stability components in the microgrid system which is not available in the published literature with a similar amount of vastness. [ABSTRACT FROM AUTHOR]

Types I, III and IV wind distributed generators show different and wide range of current sharing capacity during the occurrence of faults in the distribution feeders. In a hybrid microgrid consisting of any of the above mentioned types of wind distributed generators and photovoltaic distributed generators, the fault current in a feeder shows different behaviour which changes as per the type of distributed generators, grid/islanded connection of microgrid operation, distance of the fault from the point of common coupling and nature of the loads in the microgrid system. The novel contribution of this paper is the implementation of a fuzzy logic based adaptive protection scheme through analysis of the q0 components of fault current which are used to detect the low X/R ratio of distributed generators, modes of operation, transient reactance during the series and shunt faults in types I, III and IV wind turbines and PV integrated hybrid microgrid. Considering q0 components and transient reactance, a new relation between the relay current settings and modes of operation has been identified for adaptive relaying. The effectiveness of the proposed adaptive protection scheme for the hybrid microgrid is verified through a simulation case study using Matlab -Simulink software. [ABSTRACT FROM AUTHOR]

Apparently, battery energy storage (BES), intelligent protection and power quality are considered as independent issues. These three factors can be interlinked effectively for control of microgrid through automated demand side management (ADSM). In this context, the proposed approach may change the conventional way for microgrid operation and control giving priority to the power quality issues considering protection and BES systems. The control algorithm is implemented through fuzzy inference system based power quality monitoring index and ADSM. As a part of intelligent protection, logic table for circuit breaker (CB) coordination has been developed without/with backup for relay devices to provide ADSM. The model has been simulated using Matlab-software and validated experimentally using OPAL-RT OP4510 real-time simulator through the assessment of power quality-related parameters such as voltage, frequency, total harmonic distortion and power factor. The results are found satisfactory showing the feasibility of the proposed microgrid model. [ABSTRACT FROM AUTHOR]

The power quality issues are challenging in microgrid due to the presence of various types of renewable energy resources unlike conventional power system. So, the main objective of this research is to quantify the power quality considering the fuzziness in variation of voltage, frequency, power factor and total harmonic distortion (THD) due to the occurrence of voltage sag, swell, interruption and unbalancing in three-phase AC microgrid feeding static and rotational loads. Therefore, a novel power quality monitoring index (PQMI) is proposed to determine the status of power quality. Total 256 numbers of rules are formed for fuzzy inference system (FIS) to assess PQMI considering the acceptable limits of above mentioned four input variables as per IEEE/IEC standards. The proposed methodology is verified through Mamdani and Sugeno type FIS using Matlab-Simulink software. It is also found that the proposed PQMI is significant to define the status of microgrid even during transition from grid-connected to islanded mode and vice-versa. [ABSTRACT FROM AUTHOR]

The dynamic behaviour of microgrid system under faulty conditions makes adaptive protection a general necessity for reliable microgrid operation. In design of adaptive protection, the grid-connected and islanded modes have immense importance including grid-connected mode without distributed generators (DGs) in microgrid. In this study, a new adaptive protection scheme is proposed based on the above-mentioned modes of microgrid operation. The proposed method considers nature of DGs connected, fault location detection and fault nature identification based on quadrature and zero sequence components of fault current considering impact of X/R ratio of DGs. The proposed methodologies for adaptive protection schemes are verified in Matlab-Simulink environment and the results are found to be satisfactory while various faults are simulated at different nodes of the microgrid model. At the time of verification of effectiveness of the proposed methodologies, the time derivative of quadrature and zero-axis components of fault current are considered sufficient to instantaneously detect the fault location and fault nature in microgrid system. [ABSTRACT FROM AUTHOR]

To find a sustainable municipal solid waste (MSW) management and renewable electricity generation system is need of the hour. In modern hybrid electricity generation systems, the use of MSW on priority is not evaluated yet. To satisfy this need, a small scale MSW based microgrid is proposed and evaluated in economic and reliability terms. First, the waste of the selected city is characterized considering four seasons summer, spring, autumn and winter for a complete year. Then a microgrid system is designed using MSW processing techniques namely, anaerobic digestion (AD) and gasification that are further integrated with solar photovoltaic (PV) system, battery and the main grid. The size of the microgrid is optimized using an artificial bee colony (ABC) algorithm targeting the configuration that meets the desired system reliability requirements with minimum cost. The proposed system found as a sustainable approach to process the MSW of a small city (0.1 million population) and a reliable mean to fulfill the electricity demand of a village having 225 houses in India. The annualized system cost (ASC) of the proposed hybrid system found to be INR 5760919 with levelized cost of electricity (LCOE) 5.65 INR/kWh (0.0737 USD/kWh). The total MSW landfilling avoided cost is 451898.9 INR/year that is 17% of its processing cost. [Display omitted] • Proposed sustainable utilization of municipal solid waste for electricity generation. • Municipal solid waste based microgrid is conceptualized and optimized. • Proposed system is evaluated in economic and reliability terms. • The system avoids a significant amount of investment for landfilling of waste. [ABSTRACT FROM AUTHOR]

In many countries, the farmers find open burning is the cheapest and easiest way for removing large loads of the produced rice straw causing environmental pollution. So, finding a sustainable rice straw management system is need of the hour. In modern hybrid electricity generation systems, the use of rice straw on priority is not evaluated yet. To satisfy this need, this article proposes conceptualization and techno-economic evaluation of a small-scale rice straw based microgrid that processes the surplus rice straw of a village having 250 houses and 900 acres of cultivated land for power generation. The system is capable to process the 1128 tonne/year of 1surplus rice straw and meet the electrical load demand of the same village. The gasification technique is used to process the rice straw, which is further integrated with solar, battery and the utility grid. The optimum size of the microgrid is found using artificial bee colony algorithm. The economic evaluation of the proposed microgrid is organized on the basis of net present cost, annualized system cost and levelized cost of electricity (LCOE). The LCOE of the proposed system is found to be acceptable which is 6.70 INR/kWh (0.089 $/kWh). [Display omitted] • Proposed sustainable utilization of surplus rice straw for electricity generation. • Rice straw based microgrid is conceptualized and optimized for a rural community. • Proposed system is evaluated in economic and reliability terms. • The proposed system is found economically feasible and reliable. [ABSTRACT FROM AUTHOR]