Power
Babak Keshavarz Zahed; Mohammad Hassan Moradi
Abstract
The penetration of double-fed induction generators (DFIG) as renewable energy sources (RES) in power systems leads to fluctuations caused by wind energy. Therefore, based on this challenge, a wide area damping controller (WADC) has been designed to compensate the oscillatory modes by a static synchronous ...
Read More
The penetration of double-fed induction generators (DFIG) as renewable energy sources (RES) in power systems leads to fluctuations caused by wind energy. Therefore, based on this challenge, a wide area damping controller (WADC) has been designed to compensate the oscillatory modes by a static synchronous series compensator (SSSC). In addition to the design of WADC for SSSC, a parallel compensator in the form of a supercapacitor energy storage system (SCESS) has been used in the DC link of the wind unit so that DFIG can be used optimally to supply the power system. The design method for compensating time delays in WADC is based on free weight matrices (FWM). First, based on the theory of robust control based on delay-dependent feedback, a set of constraints related to linear matrix inequality (LMI) are formulated. In the following, the free weight matrix (FWM) has been used to solve the delay-dependent time problem. The purpose of applying FWM is to extract the most optimal gain for the controller in the presence of time delay. The proposed FWM matrix tries to find the most optimal gain in the controller with the help of an iterative algorithm based on the linearization of conical complement. The simulation results have been implemented in the MATLAB software environment after obtaining the critical modes in the nonlinear time domain on the power system of 16 improved machines. Based on the simulation results, the robustness of the proposed controller under various uncertainties is clearly shown in this paper.
Telecommunications
Patikiri Arachchige Don Shehan Nilmantha Wijesekara
Abstract
Network Virtualization (NV) techniques enable high scalability and isolation by abstracting physical resources to provide a logical network representation that can coexist with a physical networking framework. Traditional NV is prone to security attacks and has lower privacy and trustfulness compared ...
Read More
Network Virtualization (NV) techniques enable high scalability and isolation by abstracting physical resources to provide a logical network representation that can coexist with a physical networking framework. Traditional NV is prone to security attacks and has lower privacy and trustfulness compared to blockchain-established NV. We diagnose the BC-established NV construct under 5 segments and closely appraise the literature in reference to NV technique, virtualization technology, BC-related properties, and network properties. We racked up a starting sample of 85 sources by filtering literary work for qualifying conditions searched from article retrieval platforms, engaging a rigorous and prolonged approach. Anchored from this research, in BC-established NV, we demonstrate that BC can act as a broker/manager for NV, act as a secure storage by preventing double-spending attacks, provide secure virtual network embedding with high fault tolerance, engage BC and smart contacts for resource trading in the process of NV, engage dedicated consensus approaches to reach agreement for NV among multiple parties for reducing security attacks, and establish BC-established access control for NV. Complete interpretation disseminates that from interpreted BC-established NV schemes, 45% engage BC and smart contracts for agreements and resource trading for NV, 95% engage regular BC architecture, Proof-of-Work (PoW) and Practical Byzantine Fault Tolerance (PBFT) being the most frequently used consensus, 80% engage the overlay network concept, and it has been engaged abundantly (27.5%) in 5G networks. Finally, we deliberate the possibilities and obstacles of the framework of blockchain-established NV and then provide suggestions to suppress them.
Power
Iman Ali Hassanvand; Javad Ebrahimi; Mahyar Abasi
Abstract
The dominant measures taken in distribution networks to solve the problem of voltage instability include feeder reconfiguration techniques, allocation of capacitor banks, use of tap changers, etc. However, these traditional methods suffer from numerous problems. Many studies have been carried out to ...
Read More
The dominant measures taken in distribution networks to solve the problem of voltage instability include feeder reconfiguration techniques, allocation of capacitor banks, use of tap changers, etc. However, these traditional methods suffer from numerous problems. Many studies have been carried out to solve these problems in recent years. Compared with traditional methods, reactive power control (RPC) of photovoltaic (PV) inverters does not require additional investment, and given that PV inverters often function at a capacity below their rated value, the excess capacity can be utilized to assist in supplying reactive power to the grid. However, achieving voltage regulation in imbalanced distribution networks via RPC is a complex issue. Hence, the primary objective of this work is to utilize the reactive power capacity of photovoltaic inverters to achieve decentralized regulation of effective voltage of the network using a consensus algorithm and PID controller in two stages.
Power
Mohammad Abedini; Mahyar Abasi
Abstract
Maintaining power system stability can be challenging due to low-frequency fluctuations. Traditionally, power system stabilizers (PSS) and unified power flow controllers (UPFC) have been used to address this issue. This paper proposes a novel approach that leverages both PSS and UPFC simultaneously, ...
Read More
Maintaining power system stability can be challenging due to low-frequency fluctuations. Traditionally, power system stabilizers (PSS) and unified power flow controllers (UPFC) have been used to address this issue. This paper proposes a novel approach that leverages both PSS and UPFC simultaneously, controlled by an optimized fuzzy logic system. The proposed fuzzy controller aims to enhance the efficiency of both PSS and UPFC, ultimately boosting system damping. The controller takes two key inputs: changes in angular speed and power angle. To dynamically adjust its response to changing system conditions, a shuffled frog leaping algorithm optimizes the fuzzy controller's gains. To assess the effectiveness of the controller, simulations are conducted across three different loading levels for the studied system. The results are presented for each stage and demonstrate a significant reduction in overshoot and improved overall system damping. Our method achieves a remarkable 43% enhancement in damping compared to PSS, a 45% improvement over UPFC alone, and a staggering 48% advantage over the hybrid PSS-UPFC approach.
Power
Musa Khosravi; Saeed Hasanvand; Mahyar Abasi; Mohammad Esmaeil Hassanzadeh
Abstract
Considering the challenges of using fossil fuels including price and pollution and the increasing development of electric vehicles, the energy supply from other sources should be considered. One of the main challenges of electric vehicles is their impact on the distribution network, especially the time ...
Read More
Considering the challenges of using fossil fuels including price and pollution and the increasing development of electric vehicles, the energy supply from other sources should be considered. One of the main challenges of electric vehicles is their impact on the distribution network, especially the time of charging and its coincidence with the peak load of the network, which causes an increase in power consumption, double pressure on the network, and more and faster depreciation of distribution network equipment. Also, producing more energy during peak times leads to increased costs and air pollution. In this paper, the use of renewable energy to charge electric vehicles is investigated in such a way that the consumers of electric vehicles use solar panels and batteries to store solar energy so that it can be used for charging during peak times. The costs of installing solar panels, the consumption of electric vehicles, the amount of energy generation, as well as the emission of fossil fuel pollutants that fossil power plants produce at peak times have been investigated. Furthermore, a comparison has been made between the use of renewable and non-renewable energy. Consequently, the proposed method is about 112494 dollars more economical than the system without renewable energy. It is also suggested to consider incentives from the government for the consumer to reduce the capital and operating cost of the photovoltaic system to diminish the investment return time.
Power
Arash Rohani; Javad Ebrahimi; Shirin Besati
Abstract
A two-layer combined control method is developed for a four-leg Distribution Static Synchronous Compensator (DSTATCOM). The method aims at harmonics reduction, demand-generation equilibrium, power factor modification, voltage adjustment, and neutral current modification in a 3ph 4-wire distribution system. ...
Read More
A two-layer combined control method is developed for a four-leg Distribution Static Synchronous Compensator (DSTATCOM). The method aims at harmonics reduction, demand-generation equilibrium, power factor modification, voltage adjustment, and neutral current modification in a 3ph 4-wire distribution system. In the first layer, a recursive Least Error Square algorithm (RLES) based on a new fuzzy logic-based variable forgetting factor is used for Real-time estimation of voltage and current signals and their constituting components. The second layer’s duty is to extract the reference currents using the outputs of the first layer. Besides the high accuracy and convergence speed, the suggested algorithm is independent of coordinate transformations and complex computation when attempting to derive the reference currents of DSTATCOM. To enhance the dynamic performance of DSATATCOM, an adaptive hysteresis band current controller was utilized to generate switching signals. The effectiveness of the presented control strategy was verified via simulation studies implemented in MATLAB/Simulink environment.
Control
Behnam Ersi Alambaz; Mohsen Ghalehnoie; Hamid Reza Moazami
Abstract
This paper explores the impact of two types of experiments, known as "long pulse" and "short pulse," experiments, on identifying models for Lithium-ion batteries. The focus is on improving the estimation of the state of charge (SoC) using an extended Kalman filter. The results consistently demonstrate ...
Read More
This paper explores the impact of two types of experiments, known as "long pulse" and "short pulse," experiments, on identifying models for Lithium-ion batteries. The focus is on improving the estimation of the state of charge (SoC) using an extended Kalman filter. The results consistently demonstrate that applying the extended Kalman filter to models identified through long pulse experiments outperforms those identified through short pulse experiments in estimating battery SoC and terminal voltage. The article delves into the reasons for this improvement from both circuit and electrochemical perspectives, providing insights into the obtained results. Thus, the study advocates for the preference of long pulse strategies to enhance the performance of Lithium-ion batteries, offering insights that contribute to the development of innovative and sustainable energy storage solutions.
Power
Yasaman Abbasi Chahardah Cheriki; Hossein Farzin; Elaheh Mashhour
Abstract
In recent decades, the probability of natural disasters has increased due to climate change. As a result, the discussion of resilience in the power system literature was raised. One consequence of these events is the unwanted operation of some power system equipment, which causes unexpected blackouts ...
Read More
In recent decades, the probability of natural disasters has increased due to climate change. As a result, the discussion of resilience in the power system literature was raised. One consequence of these events is the unwanted operation of some power system equipment, which causes unexpected blackouts and increases the value of energy not supplied (ENS) in the system. Insulators are important components of the power system that have a great impact on the continuity of supply. Electrical flashover in insulators causes a decrease in their insulation strength and might lead to short circuit faults in the power system. In this paper, the effect of dust storms and humidity on the probability of transmission network insulators flashover is investigated. The studied insulator is simulated in Electrical AutoCAD software, and after applying pollution and moisture in COMSOL-Multiphysics software, the distribution of potential and electric field on the studied insulator is obtained using the finite element method (FEM). In order to determine the probability of insulation flashover, the candidate points for arc occurrence are selected using the roulette wheel method in MATLAB software, and the insulation flashover probability curve is determined in different amounts of dust pollution and three humidity levels of 65%, 80%, and 95%. The effects of increasing the creepage distance and using silicone rubber materials that have hydrophobic properties are investigated, and various sensitivity analyses are conducted. The results indicate that both solutions can significantly reduce the flashover probability of transmission insulators.