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electric-power-system-protection
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Strategic bidding of generating units in competitive electricity market with considering their reliability
, Article International Journal of Electrical Power and Energy Systems ; Volume 30, Issue 3 , 2008 , Pages 193-201 ; 01420615 (ISSN) ; Ranjbar, A. M ; Shirani, A. R ; Sharif University of Technology
2008
Abstract
In the restructured power systems, they are typically scheduled based on the offers and bids to buy and sell energy and ancillary services (AS) subject to operational and security constraints. Generally, no account is taken of unit reliability when scheduling it. Therefore generating units have no incentive to improve their reliability. This paper proposes a new method to obtain the equilibrium points for reliability and price bidding strategy of units when the unit reliability is considered in the scheduling problem. The proposed methodology employs the supply function equilibrium (SFE) for modeling a unit's bidding strategy. Units change their bidding strategies and improve their...
Application of synchronised phasor measurements to wide-area fault diagnosis and location
, Article IET Generation, Transmission and Distribution ; Vol. 8, issue. 4 , 2014 , pp. 716-729 ; ISSN: 17518687 ; Ranjbar, A. M ; Sharif University of Technology
Abstract
This study introduces a novel approach to power system fault diagnosis by synchronised phasor measurements. Conventionally, faults are diagnosed through the status of protective relays and circuit breakers which are activated following a fault. However, the hidden failures of the protection system has itself often been among the main suspects of partial or widespread blackouts. This study proposes an alternative fault diagnosis approach independent of the function of the protection system. An analytical method is introduced for power system fault diagnosis using dispersed synchronised measurements and bus impedance matrix (Zbus). Fault inception is first detected by local phasor measurement...
Bus measurements protection against bad data injection in electric power grids
, Article 2017 25th Iranian Conference on Electrical Engineering, ICEE 2017, 2 May 2017 through 4 May 2017 ; 2017 , Pages 1210-1215 ; 9781509059638 (ISBN) ; Hosseini, S. H ; Farajollahi, M ; Safdarian, A ; Sharif University of Technology
Abstract
System security indices play a crucial role with regard to monitoring system statues. These indices are derived from system measurements which are prone to either intentional or unintentional noises. To alleviate the effect of intentional noises, it is required to protect measurements data from bad data injection. In this regard, this paper intends to propose an approach to determine priority order of protected bus measurements in order to negate the effects of bad data injection on security indices. With this in mind, two security severity indices, the over loading risk index and the under voltage risk index, are considered. Genetic algorithm serves to find the highest deteriorating effect...
Reliability assessment of protective relays in harmonic-polluted power systems
, Article IEEE Transactions on Power Delivery ; Volume 32, Issue 1 , 2017 , Pages 556-564 ; 08858977 (ISSN) ; Anders, G. J ; Fotuhi Firuzabad, M ; Farzin, H ; Aminifar, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Proliferation of distributed generations (DGs) and power-electronics-based loads is bringing about more harmonic-polluted power signals. While some failures may occur as a consequence of nonsinusoidal current or voltage waveforms, existing reliability models of protection relays have not taken the harmonic-related failures into consideration. This paper develops a comprehensive Markov reliability model to categorize the possible functional states of a component, say a transmission line, protected by a relay, operating in a harmonic-polluted environment. In order to make the proposed model practically tractable, it is further simplified in two ways, through merging the states of the same...
Transformer practical turn-to-turn fault detection performance using negative sequence and space vector-based methods
, Article 13th International Conference on Protection and Automation of Power System, IPAPS 2019, 8 January 2019 through 9 January 2019 ; 2019 , Pages 1-6 ; 9781728115054 (ISBN) ; Vakilian, M ; Hajipour, E ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Transformer turn-to-turn fault (TTF) is one of the most difficult failures to detect. The negative sequence percentage differential current (NSPD) and extended park vectors approach (EPVA) are the two most promising methods for detection of the TTF inception. In this paper, in order to evaluate the performance of these methods, various experimental tests are carried out to detect the TTF initiation on the winding of the transformer under different operating conditions such as: No-load operation, when an external fault or an open conductor fault is also occurred. The results show that the setting of the proper thresholds plays the main role in the reliable and secure performance of NSPD and...
Optimal placement of protective and controlling devices in electric power distribution systems: a MIP model
, Article IEEE Access ; Volume 7 , 2019 , Pages 122827-122837 ; 21693536 (ISSN) ; Safdarian, A ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
This paper presents a mathematical model for simultaneous deployment of protective devices (PDs) and controlling devices (CDs) in distribution networks. The PDs include fuses and reclosers and the CDs are remote controlled switches (RCSs) and manual switches (MSs). The model is to minimize equipment costs as well as sustained and momentary interruption costs. It considers the coordination of fuses and reclosers during temporary faults involving fuse saving and fuse blowing schemes. The model is in mixed integer programming (MIP) fashion which can be effectively solved with available solvers. The performance of the proposed model is verified through applying it to Bus 4 of Roy Billinton test...
Optimal placement of protective and controlling devices in electric power distribution systems: A MIP Model
, Article IEEE Access ; Volume 7 , 2019 , Pages 122827-122837 ; 21693536 (ISSN) ; Safdarian, A ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
This paper presents a mathematical model for simultaneous deployment of protective devices (PDs) and controlling devices (CDs) in distribution networks. The PDs include fuses and reclosers and the CDs are remote controlled switches (RCSs) and manual switches (MSs). The model is to minimize equipment costs as well as sustained and momentary interruption costs. It considers the coordination of fuses and reclosers during temporary faults involving fuse saving and fuse blowing schemes. The model is in mixed integer programming (MIP) fashion which can be effectively solved with available solvers. The performance of the proposed model is verified through applying it to Bus 4 of Roy Billinton test...
Secure one-way relaying scheme based on random difference family (RDF) lattice codes
, Article Wireless Networks ; Volume 27, Issue 7 , 2021 , Pages 4615-4634 ; 10220038 (ISSN) ; Khodaiemehr, H ; Eghlidos, T ; Panario, D ; Sharif University of Technology
Springer
2021
Abstract
In this paper, we present a one-way relaying scheme in which two wireless nodes create an information flow to each other via a single decode-and-forward (DF) relay. We consider an additional secrecy constraint for protection against an honest-but-curious relay. Indeed, while the relay should decode the source message, it should be fully ignorant about the message content. We provide a secure lattice coding strategy based on random difference families (RDF) lattice codes for unidirectional Gaussian relay channels. RDF lattice codes are carved from infinite RDF lattices using a shaping algorithm. By RDF lattice we mean a Construction A lattice with a QC-LDPC code, which is obtained from random...
Optimal distributed static series compensator placement for enhancing power system loadability and reliability
, Article IET Generation, Transmission and Distribution ; Volume 9, Issue 11 , 2015 , Pages 1043-1050 ; 17518687 (ISSN) ; Fotuhi Firuzabad, M ; Aminifar, F ; Safdarian, A ; Lehtonen, M ; Sharif University of Technology
Institution of Engineering and Technology
2015
Abstract
Distributed static series compensator (DSSC) is a member of the family of distributed flexible AC transmission system devices that can be attached directly to conductors of transmission lines. DSSCs are able to compensate for and adjust the line reactance; thus, they could be widely used in stability-limited transmission systems. Owing to economic matters, the optimal placement of DSSCs is of a great interest from practical viewpoints. This study presents an approach to find the optimal locations of DSSCs to enhance the system loadability and reliability using the DC load flow model. The optimisation problem is solved using the mixed-integer linear programming. A compromise between improving...
A single phase transformer equivalent circuit for accurate turn to turn fault modeling
, Article 24th Iranian Conference on Electrical Engineering, ICEE 2016, 10 May 2016 through 12 May 2016 ; 2016 , Pages 592-597 ; 9781467387897 (ISBN) ; Hajipour, E ; Vakilian, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Recently, an increasing concern has been raised about turn-to-turn faults (TTFs) in power transformers, because these faults can lead to severe transformer insulation failure and consequently, its outage. Generally, it is impossible to experimentally analyze the transformer behavior under such faults, since the implementation of those experiments may be substantially destructive. Therefore, computer-aided models should be developed to investigate the performance of transformer protective relays under turn-to-turn faults. So far, existing transformer models are mainly formulated to implement in the EMTP-based softwares. However, most of power system protection engineers and researchers...
A comprehensive digital protection scheme for low-voltage microgrids with inverter-based and conventional distributed generations
, Article IEEE Transactions on Power Delivery ; Volume 32, Issue 1 , 2017 , Pages 441-452 ; 08858977 (ISSN) ; Parniani, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Microgrid (MG) protection is one of the main challenges in proliferation of microgrids. Due to limited fault current feeding of inverter-based distributed generations (DGs), in islanded operation of MG, protection problems become more complicated; and, therefore, conventional protection strategies cannot be applied. Hence, new protection methods that are applicable in islanded and grid-connected modes of operation are necessary. In this paper, a comprehensive digital-relay based protection is introduced for the protection of MGs. The proposed method includes protection of lines, distributed generations, and the point of common coupling. The structure and graphical schematic of the proposed...
A series stacked IGBT switch with robustness against short-circuit fault for pulsed power applications
, Article IEEE Transactions on Power Electronics ; Volume 33, Issue 5 , May , 2018 , Pages 3779-3790 ; 08858993 (ISSN) ; Zarghany, M ; Kaboli, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
The limited value of the insolated-gate bipolar transistors (IGBTs) blocking voltage is an important issue for applying these devices to the high-voltage power converters. An effective solution is to use a series configuration of these devices in order to achieve higher voltage ratings in addition to save the interesting features such as fast rising time. To reach this goal, acceptable equal voltage sharing for the IGBTs are provided by the series stacking schemes in the normal operation.However, a considerable difference in their voltage level will be occurred in the short-circuit condition. Although the IGBT can withstand the short-circuit current in a defined time, the occurred high...
Twin growth in RF window ceramic as a criterion for the response time of protection system in high power vacuum tubes
, Article 2019 International Vacuum Electronics Conference, IVEC 2019, 28 April 2019 through 1 May 2019 ; 2019 ; 9781538675342 (ISBN) ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The ceramic fracture in output RF window is one of the most important failure factors in high power microwave sources. Fast protection systems are used to protect the source. The methods for determining the required protection response time are conservative and rough. In this paper, an investigation is presented about the twin growth in the ceramic of RF window in faulty condition. It is shown that the twin growth in ceramic can be a reliable figure of merit for the response time calculation of the microwave source protection system
Reliability evaluation of power grids considering integrity attacks against substation protective IEDs
, Article IEEE Transactions on Industrial Informatics ; Volume 16, Issue 2 , 2020 , Pages 1035-1044 ; Fotuhi Firuzabad, M ; Farzin, H ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
Secure operation of protective intelligent electronic devices (IEDs) has been recognized as a crucial issue for power grids. By gaining access to substation IEDs, intruders can severely disrupt the operation of protection systems. This paper develops an analytical reliability assessment framework for quantifying the impacts of the hypothesized integrity attacks against protection systems. Petri net models are used to simulate possible intrusion scenarios into substation networks. The cyber network model is constructed from firewall, intrusion prevention system (IPS), and password models, which are three types of defense mechanisms for protecting substation networks. In this paper, two main...
Transmission grid fault diagnosis by wide area measurement system
, Article IEEE PES Innovative Smart Grid Technologies Conference Europe ; 2012 ; 9781467325974 (ISBN) ; Ranjbar, A. M ; Sharif University of Technology
2012
Abstract
While the importance of wide area measurement system (WAMS) consisting of phasor measurement units (PMUs) is recognized, there are still unidentified applications that can be addressed with the advance of technology. Traditionally, power system operators diagnosed the fault point through the status of protective relays and circuit breakers of the protection system. In large blackouts, however, the malfunction of protection system has itself often been among the suspects of the disaster. This paper proposes an alternative fault diagnosis approach independent of the function of protection system, utilizing PMU data and bus impedance matrix (Zbus). First, the proposed method diagnoses the fault...
A decision tree-based method for power system fault diagnosis by synchronized Phasor Measurements
, Article IEEE PES Innovative Smart Grid Technologies Conference Europe ; 2012 ; 9781467325974 (ISBN) ; Dobakhshari, A. S ; Ranjbar, A. M ; Sharif University of Technology
2012
Abstract
This paper introduces a novel approach for power system fault diagnosis based on synchronized phasor measurements during the fault. The synchronized measurements are obtained in real time from Phasor Measurement Units (PMUs) and compared with offline thresholds determined by decision trees (DTs) to diagnose the fault. The DTs have already been trained offline using detailed power system analysis for different fault cases. While the traditional methods for fault diagnosis use the status of protective relays (PRs) and circuit breakers (CBs) to infer the fault section in the power system, the proposed method uses the available signals following the fault and thus can be trusted even in case of...
A simple three-phase model for distributed static series compensator (DSSC) in Newton power flow
, Article 2009 Asia-Pacific Power and Energy Engineering Conference, APPEEC 2009, Wuhan, 27 March 2009 through 31 March 2009 ; 2009 ; 21574839 (ISSN); 9781424424870 (ISBN) ; Mokhtari, H ; Wuhan University; IEEE Power and Energy Society; Chinese Society for Electrical Engineering; Scientific Research Publishing ; Sharif University of Technology
2009
Abstract
Load flow problems have always been an important issue in power system analysis and require proper modeling of system components. In this regard Flexible AC Transmission System (FACTS) controllers are modern devices that their modeling specially the series type is a challenging topic. This paper describes a three-phase model for Distributed Static Series Compensator (DSSC) based on extending the Static Synchronous Series Compensator (SSSC) model in Newton power flow. To extend the SSSC model the following two differences must be considered; three completely independent phases and the existence of several modules in a DSSC system. Simulation results on the IEEE 30-bus system and a five bus...