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 ...
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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, ...
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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 ...
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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
Ali Morsagh Dezfuli; Mahyar Abasi; Mohammad Esmaeil Hasanzadeh; Mahmood Joorabian
Abstract
The utilization of distributed generation (DG) in today's power systems has led to the emergence of the concept of microgrids, in addition to changing the mode of generating and supplying the energy required for network electrical loads. When a microgrid operates in the island mode, energy generation ...
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The utilization of distributed generation (DG) in today's power systems has led to the emergence of the concept of microgrids, in addition to changing the mode of generating and supplying the energy required for network electrical loads. When a microgrid operates in the island mode, energy generation sources are responsible for controlling the microgrid’s voltage and frequency. As the microgrid frequency is proportional to the amount of power generated by the DG, the microgrid requires a precise power-sharing strategy. Considering that DGs do not usually have stable output power despite the importance of power stability, the present paper addresses the voltage and frequency control of an islanded microgrid by considering the power generation uncertainties caused by disturbances and the varying power output of DGs. Given that the disturbance on the first DG's input current is 0.2 A, which is approximately 2.2% of the steady-state value, a simulation was performed, and it was observed that the maximum voltage variation of each bus in the worst case was 0.59% for the first bus and 0.53% for the second bus, which means that the controller could control the voltage and frequency values within the permissible range. If the controller is not used, the change in the frequency of each bus will be 10 times, and the voltage change will be 5 times as great as that of the case the controller is used.
Power
Narges Yousefi; Mahmood Joorabian; Mahyar Abasi
Abstract
An obstacle in managing economic dispatch is the integration of diverse factors such as pollution and heat. By introducing the price penalty coefficient, this class of two-objective problems is transformable to a single-objective form. The formulation considers various practical constraints of the system, ...
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An obstacle in managing economic dispatch is the integration of diverse factors such as pollution and heat. By introducing the price penalty coefficient, this class of two-objective problems is transformable to a single-objective form. The formulation considers various practical constraints of the system, including non-smooth cost functions, the balance of production, demand, and losses, and the limitation of power generation by active generators. One of the fundamental difficulties in tackling these types of complex problems lies in the algorithms and solvers employed to identify optimal solutions for a range of operation problems. The rain optimization algorithm (ROA) has been utilized in this paper. ROA is derived from the inherent tendency of raindrops to seek out the lowest areas on the earth's surface. This algorithm possesses exceptional efficacy in resolving problems characterized by stringent constraints and is adept at circumventing local optima. To validate the proposed method for cost and emission reduction, the scheme under consideration has been developed using software on standard systems. The implementation of the scenarios has revealed that the limits of the power system have led to a decrease in the overall generation cost of fossil fuel generation units. In this article, the ROA algorithm managed to plan the production with an optimal cost of 38481.54 dollars in case 1, which obtained a more optimal value than all the compared algorithms. This reduction in cost is considered one of the triumphs of the optimization problems. The results showcased and juxtaposed in the software simulation verify the effective performance of the suggested approach in comparison to prior research.
Power
Mahyar Abasi; Nima Heydarzadeh; Arash Rohani
Abstract
The phenomenon of broken conductor faults (BCFs) in power transmission lines and, consequently, the suspension of the hot-line with no connection to ground, tower, or other conductive/non-conductive bodies is amongst special faults in terms of fault detection and location in the protection industry. ...
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The phenomenon of broken conductor faults (BCFs) in power transmission lines and, consequently, the suspension of the hot-line with no connection to ground, tower, or other conductive/non-conductive bodies is amongst special faults in terms of fault detection and location in the protection industry. Once such a failure occurs, the current of the faulty phase does not increase, which leads to the inability of standard fault detection functions in detecting the event. On the other hand, the variable nature of transmission line parameters due to weather conditions leads to misoperation and malfunction of fault detection and protection schemes of industrial relays in some cases. This paper, for the first time, presents a BCF location scheme without requiring line parameters data and only using magnitudes of current and voltage phasors of a single terminal based on Group Method of Data Handling (GMDH). In this method, a function is interpolated, the inputs of which are the current and voltage of the faulty phase, and its output are the accurate location of the fault. The function can be developed for all topologies of transmission lines. The proposed method is implemented in the MATLAB software and the obtained results verify the solidity and perfect performance of the method for different fault conditions.