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One of the intrinsic properties of Distribution networks, resilience, is the ability to resist, adjust, and recover from extreme, high-impact, low-probability events such as earthquakes, floods, hurricanes, thunderstorms, and cyber and physical attacks. Besides, the uncertainty of the network elements has a significant effect on the operation of the distribution system. Operators require methods a...Show More
The smart and sustainable development of power grids has brought about numerous power quality disturbances (PQD) that threaten the efficiency and reliability of the smart grids. Detecting and classifying these disturbances is crucial to taking appropriate corrective action to mitigate possible impacts. While machine learning (ML) algorithms are at the center of attention for most PQD detection pro...Show More
Due to the increasing trend of electric energy demand every year around the world and the lack of replacement or increase of electricity distribution lines, the probability of congestion in modern networks has increased. Despite the expansion of modern congestion management methods, load shedding is still one of the best options for congestion relief in some networks when necessary. In this articl...Show More
Nowadays, the high penetration of distributed generation resources on the consumers’ side caused changes in the power grid. These resources have evolved the role of consumers in traditional networks and created a new role called prosumers in future power networks. By producing electricity, in addition to meeting their needs, prosumers are trying to sell their excess electricity production in the e...Show More
Reliability is a fundamental factor in distribution network expansion planning. To achieve high reliability, urban distribution networks operate in a meshed and radial manner, where the interrupted load can be restored to adjacent feeders through post-fault connection lines. Due to the integration of new technologies, power distribution systems have become more complex in recent years. In this art...Show More
Due to the increase in the penetration rate of electric vehicles, according to different governments’ emphasis on reducing carbon emissions, the demand for electricity has also increased. An increase in unmanaged electricity demand can cause severe problems in electricity distribution networks, such as increasing line congestion. Therefore, demand management for electric vehicle charging is one of...Show More
The change in the topology and state of active distribution networks (ADNs) is one of the crucial challenges that might affect the protection schemes. The conventional protection schemes based on a static topology result in coordination constraint violations in other topologies due to the outage of upstream substations and distributed generation units. This paper proposes adaptive and combinationa...Show More
This paper proposes obtaining maximum and minimum daily cumulative energy curves and introduces novel hourly and daily energy flexibility indices. Also, it develops a generic methodology that quantifies and formulates energy flexibility as the possible power increase (P_in) or decrease (P_dec) within operational limits. The proposed method can be applied to derive maximum and minimum energy flexib...Show More
Microgrids (MG) that are located near each other may have varying levels of power supply redundancy. Therefore, interconnecting two or more microgrids into one multi-microgrid (MMG) system can lead to improved overall power supply economics and reliability. Multi-microgrid systems are often more complex than single microgrids. Reliability research is of paramount importance for MMG design and oper...Show More
This paper addresses the event-triggered distributed cooperative secure secondary control for islanded cyber-physical inverter-based ac microgrids (MGs) under the energy-limited denial of service (DoS) attacks. The DoS attack refers to the prevention of information exchange among Distributed Energy Resources (DERs) in the secondary control level. In this paper, an event-triggered mechanism (ETM) i...Show More
In this article, we cope with the parameter estimation (PE) of the synchronous generator (SG) and the excitation systems. The field winding signals are not available for accurate measurement in the proposed strategy. To this end, a robust unknown input reconstruction observer is exploited to determine both SG unknown inputs, including the mechanical torque and field voltage, under disturbances inf...Show More
This article presents an enhanced control strategy for renewable energy resources connected to the grid through voltage-sourced converters (VSCs) in microgrids. The proposed scheme contains a voltage control loop with the minimum inverter switching, a power-sharing controller with the minimum inverter switching, a negative-sequence current controller, and a loop to identify the control system oper...Show More
In this study, a structure is presented to manage the energy of the electric vehicle (EV) charger, which will be able to handle the energy of the charger at the same time, predict the production of solar generators located in the charging stations, and manage the EV charger in the workplace busbar. Uncertainty is often considered in the battery capacity of EVs. The objective function is to increas...Show More
This paper presents a distributed fault-tolerant finite-time control scheme for the secondary voltage and frequency restoration of islanded inverter-based Alternating Current (AC) Microgrids (MGs) considering input saturation and faults. Most existing distributed methods commonly design the secondary control layer based on ideal conditions of the control input channels of the MG without any faults...Show More
DC microgrids can be operated under a hierarchical control strategy, and it needs a communication-based layer. The implementation of digital controllers and the communication infrastructure can make a dc microgrid vulnerable to cyber-attacks. This article introduces an approach based on Artificial Intelligence (AI) to detect and mitigate cyber-attacks in a dc microgrid. The proposed method is base...Show More
Over the past decade, the high penetration of renewable-based distributed generation (DG) units has witnessed a considerable rise in electrical networks. In this context, direct current (DC) microgrids based on DGs are being preferred due to having less complexity for the establishment and control. At the same time, they offer higher efficiency and reliability compared to their alternating current...Show More
Accurate locating of the faulty section is desired in dc microgrid due to the presence of power electronic converters and low-impedance cables. Some of the existing schemes consider power sources at only one end of the line; thus, assume that the fault current is injected from only one end of the line. This assumption is not true in the case of meshed dc microgrids, where fault current would be su...Show More
Direct current (DC) microgrids can be considered as cyber-physical systems due to implementation of measurement devices, communication network, and control layers. Consequently, dc microgrids are also vulnerable to cyber-attacks. False-data injection attacks (FDIAs) are a common type of cyber-attacks, which try to inject false data into the system in order to cause the defective behavior. This art...Show More
Inherent nonlinearities and uncertainties are inseparable parts of the real-life engineering systems, which make theoretical analyzes and control system designs more challenging. Usually, most of the physical parts in control systems such as controllers and actuators are subjected to saturation. On the other hand, uncertainties are ubiquitous in the physical systems, which demand some necessities ...Show More
This article presents a high-performance hardware-in-the-loop (HIL) system aimed to assist experts in developing and testing power electronics control board and their logic with real-time (RT) models of both electrical and mechanical components. For demonstrating the effectiveness of this system for HIL testing, a new industrial doubly-fed induction generator (DFIG) control board is tested based o...Show More
Unexpected natural disasters or physical attacks can have various consequences, including extensive and prolonged blackouts on power systems. Energy systems should be resistant to unwanted events, and their performance is not easily affected by such conditions. The power system should also have sufficient flexibility to adapt to severe disturbances without losing its full version; it should restor...Show More
Nowadays, the problem of the proper charging of plug-in hybrid electric vehicles (PHEVs) has become increasingly difficult because there is high uncertainty on both the demand and supply sides of microgrid (MG) systems, which may reduce efficiency and increase the cost of MG systems. Available solutions to these challenges are the application of energy storage systems and energy exchange with the ...Show More
In this article, a unified, robust hierarchical control structure is proposed for operating networked multi distributed generation grid-forming power converters in islanded alternating current (ac) microgrids (MGs). The primary control level stabilizes the frequency and the voltage of an ac MG through a cascaded structure, consisting of a droop controller, a mixed $H_2$/$H_\infty$-based voltage co...Show More
In this article, a novel robust distributed cooperative control (RDCC) scheme is proposed to be used in the secondary layer of off-grid (autonomous) ac microgrids (MG). The MG, including heterogeneous units such as distributed generation and battery energy storage systems. Most of the reported studies have assumed the ideal conditions to communicate among units. They have not considered any uncert...Show More
In this article, a new robust hierarchical control scheme is proposed for off-grid (autonomous) voltage-sourced converter (VSC)-based alternative current (ac) microgrids (MGs). The main focus of this article is devoted to the primary layer, including the cascade structure of inner (current), outer (voltage), the virtual impedance, and droop control loops. In the inner control loop, a robust contro...Show More