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voltage-recovery
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Investigating the effect of ambient temperature on fault-induced delayed voltage recovery events
, Article IET Generation, Transmission and Distribution ; Volume 14, Issue 9 , 2020 , Pages 1781-1790 ; Karimi, M. R ; Hajipour, E ; Farzin, N ; Hashemi, S. M ; Agheli, A ; Ayoubzadeh, H ; Ehsan, M ; Sharif University of Technology
Institution of Engineering and Technology
2020
Abstract
The high penetration of residential air conditioners (RACs) poses a growing concern in emerging fault-induceddelayed voltage recovery (FIDVR) in power systems. FIDVR is expected to be a significant threat to the stability and reliability offuture power grids. Hence, the system planners should carry out appropriate simulation studies to mitigate the severeconsequences of FIDVR events. A key question to implement these studies is how to determine the worst condition whichresults in FIDVR. Most of the actual FIDVR events have been experienced in the hot hours of the day and this issue makes onecurious to think about the relationship between the FIDVR events and the ambient temperature. In this...
Presenting Practical Solutions to Mitigate the Effects of Fault Induced Delayed Voltage Recovery (FIDVR) Phenomenon on the Special Protection Systems of Power Network
, M.Sc. Thesis Sharif University of Technology ; Vakilian, Mehdi (Supervisor) ; Hajipoor, Ehsan (Co-Supervisor)
Abstract
Fault Induced delayed voltage Recovery (FIDVR) is a phenomenon that occurs due to the behavior of motor loads such as A/C loads during voltage drop due to fault occurrence in the transmission, sub-transmission and distribution network. The electric motors used in air conditioning systems have a constant torque and inertia, and may therefore be stalled due to voltage drops And after the fault clearing, by dragging high reactive power and a current of 5 or 6 times the rated current, it leads to a continued voltage drop and a slowdown in the voltage recovery process. After a while, the thermal protection devices of the motors can cause significant load losses and subsequently increase the...
An Improved aggregated model of residential air conditioners for FIDVR studies
, Article IEEE Transactions on Power Systems ; Volume 35, Issue 2 , 2020 , Pages 909-919 ; Saber, H ; Farzin, N ; Karimi, M. R ; Hashemi, S. M ; Agheli, A ; Ayoubzadeh, H ; Ehsan, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Stalling of residential air conditioners (RACs) following a transient fault can delay the voltage recovery ranging from 3 to 20 seconds. This phenomenon is referred to as fault-induced delayed voltage recovery (FIDVR). Several aggregated RAC models have been presented to replicate the actual FIDVR events. However, they usually have two main drawbacks as: i) considering independent stalling voltage and stalling time for all RACs, ii) resulting in only two ultimate modes; either 100% stalled or 100% normal running. This paper amends the abovementioned shortcomings by proposing a simple and effective performance-based RAC model. The proposed model utilizes a simple explicit relation between the...
Performance assessment of thermophotovoltaic application in steel industry
, Article Solar Energy Materials and Solar Cells ; Volume 157 , 2016 , Pages 55-64 ; 09270248 (ISSN) ; Sharif University of Technology
Elsevier
2016
Abstract
The potential for using Thermophotovoltaic (1TPV) generators as an alternative for recovering energy losses in steel production industry is assessed. A mathematical model for the assessment of the performance of TPV application in the iron and steel industry has been developed. In order to support the mathematical model, a sample TPV apparatus in laboratory scale based on an IR emitter has been designed and assembled. The key modeling parameters of TPV generator include: the open circuit voltage, the short circuit current density and fill factor of the TPV cell. These parameters have been considered in the model as functions of several variables such as: the emitter (hot steel slab)...
Optimal reactive power planning in active distribution systems for steady-state and transient characteristics improvement
, Article 27th Iranian Conference on Electrical Engineering, ICEE 2019, 30 April 2019 through 2 May 2019 ; 2019 , Pages 503-508 ; 9781728115085 (ISBN) ; Mirnezhad, H ; Parniani, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Numerous operational issues including voltage deviation and instability arise in distribution networks with insufficient reactive support. Static issues have been widely studied for years, and some dynamic ones are recently gaining attention due to the proliferation of distributed generation (DG). In this paper, a two-step reactive compensation planning procedure is proposed to address these challenges. In the first step, passive compensators are optimally sited and sized using a metaheuristic algorithm in order to improve steady-state indices including power efficiency, voltage profile, and static voltage stability. In the second step, a static synchronous compensator (Statcom) is located...