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Optimal unified power flow controller application to enhance total transfer capability
, Article IET Generation, Transmission and Distribution ; Volume 9, Issue 4 , 2015 , Pages 358-368 ; 17518687 (ISSN) ; Fotuhi Firuzabad, M ; Othman, M ; Sharif University of Technology
Institution of Engineering and Technology
2015
Abstract
For a power transfer path, total transfer capability (TTC) represents maximum power that can be transferred over the transmission system. Unified power flow controller (UPFC) is a device that can be used to increase in TTC. This study presents a new method for optimal UPFC application to minimise power loss while enhancing TTC. Based on UPFC injection model, the solution region of UPFC parameters is first found using the proposed method to maximise TTC. It then searches the solution region to find optimal UPFC control mode and setting to minimise system power loss. The proposed method is applied to the IEEE-Reliability Test System and the UPFC application impact are evaluated. Comparative...
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...
PHEVs centralized/decentralized charging control mechanisms: Requirements and impacts
, Article 45th North American Power Symposium, NAPS 2013 ; September , 2013 ; 9781479912551 (ISBN) ; Abbaspour, A ; Fotuhi Firuzabad, M ; Dehghanian, P ; Sharif University of Technology
2013
Abstract
This paper investigates the main features of the PHEV centralized and decentralized charging control mechanisms, their requirements and also impacts on distribution system performance. A home-based charging control scenario as well as a coordinated charging control algorithm for the charging management of PHEVs is devised in this paper. Both the owner preferences and system operator concerns are taken into consideration in an optimization-based framework. The total network losses and charging costs are set as the constraints to the proposed optimization approach. Various aspects of the two mechanisms are discussed and comprehensively compared by their application on the IEEE 34-bus test...
Composite power system adequacy assessment based on postoptimal analysis
, Article Turkish Journal of Electrical Engineering and Computer Sciences ; Volume 21, Issue 1 , 2013 , Pages 90-106 ; 13000632 (ISSN) ; Fotuhi Firuzabad, M ; Aminifar, F ; Sharif University of Technology
2013
Abstract
The modeling and evaluation of enormous numbers of contingencies are the most challenging impediments associated with composite power system adequacy assessment, particularly for large-scale power systems. Optimal power flow (OPF) solution, as a widely common approach, is normally employed to model and analyze each individual contingency as an independent problem. However, mathematical representations associated with diverse states are slightly different in one or a few generating units, line outages, or trivial load variations. This inherent attribute brings a promising idea to speed up the contingency evaluation procedure. In this paper, postoptimal analysis (POA), as a well-recognized...
Modified artificial bee colony algorithm based on fuzzy multi-objective technique for optimal power flow problem
, Article Electric Power Systems Research ; Volume 95 , 2013 , Pages 206-213 ; 03787796 (ISSN) ; Hosseinian, S. H ; Ghazanfari, A ; Sharif University of Technology
2013
Abstract
This paper presents a fuzzy based modified artificial bee colony (MABC) algorithm to solve discrete optimal power flow (OPF) problem that has both discrete and continuous variables considering valve point effects. The OPF problem is formulated as a multi-objective mixed-integer nonlinear problem, where optimal settings of the OPF control variables for simultaneous minimization of total fuel cost of thermal units, total emission, total real power losses, and voltage deviation are obtained. The proposed approach is applied to the OPF problem on IEEE 30-bus and IEEE 118-bus test systems. The performance and operation of the proposed approach is compared with the conventional methods. The...
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...
Iteration PSO with time varying acceleration coefficients for solving non-convex economic dispatch problems
, Article International Journal of Electrical Power and Energy Systems ; Volume 42, Issue 1 , November , 2012 , Pages 508-516 ; 01420615 (ISSN) ; Rabiee, A ; Soroudi, A ; Ehsan, M ; Sharif University of Technology
2012
Abstract
This paper presents a novel heuristic algorithm for solving economic dispatch (ED) problems, by employing iteration particle swarm optimization with time varying acceleration coefficients (IPSO-TVAC) method. Due to the effect of valve-points and prohibited operation zones (POZs) in the generating units' cost functions, ED problem is a non-linear and non-convex optimization problem. The problem even may be more complicated if transmission losses are taken into account. The effectiveness of the proposed method is examined and validated by carrying out extensive tests on three different test systems. Valve-point effects, POZs, ramp-rate constraints and transmission losses are modeled. Numerical...
Pricing of transmission services: An efficient analysis based on fixed and variable imposed costs
, Article 2012 11th International Conference on Environment and Electrical Engineering, EEEIC 2012 - Conference Proceedings, 18 May 2012 through 25 May 2012, Venice ; 2012 , Pages 407-412 ; 9781457718281 (ISBN) ; Hosseini, S. H ; Moeini-Aghtaie, M ; Sharif University of Technology
IEEE
2012
Abstract
Open access to transmission networks as well as designing an efficient cost allocation method are the key points that provide free competition for participants in power market. Restructuring in power systems has created new challenges which emphasize the development and fairness of economical criteria such as pricing of different services in market environment. Besides, the charge of network usage is a controversial subject, itself. To address this problem, many methods for transmission line cost allocation have been proposed. Amongst them, MW-Mile methods are based on the extent of use concept. Inability to take various fixed together with variable imposed costs into account can be...
Simultanous emergency demand response programming and unit commitment programming in comparison with interruptible load contracts
, Article IET Generation, Transmission and Distribution ; Volume 6, Issue 7 , 2012 , Pages 605-611 ; 17518687 (ISSN) ; Duki, E. A ; Kia, M ; Soroudi, A ; Ehsan, M ; Sharif University of Technology
2012
Abstract
Different reasons such as power system restructuring, electricity price variation in some hours of a day and growth in the fuel price, have led to more attention to demand response (DR) programmes for consumers. Two important issues in DR programmes are emergency demand response programming (EDRP) and Interruptible/Curtail able (I/C) programme that is utilised as interruptible load contracts (ILC). The EDDR is utilised to decrease the consumption in peak load or critical hours of the day. This occurs by means of customer's behaviour in response to the incentives. However, the curtailment of voluntarily loads in the critical hours considering the consumer requirements is an action that can be...
Optimal reactive power dispatch for improving voltage stability margin using a local voltage stability index
, Article Energy Conversion and Management ; Volume 59 , 2012 , Pages 66-73 ; 01968904 (ISSN) ; Vanouni, M ; Parniani, M ; Sharif University of Technology
2012
Abstract
Management of reactive power resources is vital for stable and secure operation of power systems in the view point of voltage stability. This paper deals with the management of on-load tap changers (OLTCs) and dynamic VAR sources (including synchronous generators, synchronous condensers, and shunt reactive power compensators) to improve voltage stability margin (VSM) of power systems. This problem is usually called optimal reactive power dispatch (ORD) in the literature. The main contribution of the paper is to introduce a new objective function for the ORD problem. The proposed objective function is derived based on a local voltage stability index, called DSY, and has a strong correlation...
Voltage stability improvement through centralized reactive power management on the Smart Grid
, Article 2012 IEEE PES Innovative Smart Grid Technologies, ISGT 2012, 16 January 2012 through 20 January 2012 ; 2012 ; 9781457721588 (ISBN) ; Abbaspour-Tehrani Fard, A ; Dobakhshari, A. S ; Ranjbar, A. M ; Sharif University of Technology
2012
Abstract
With the increasing penetration of renewable energies as distributed generation (DG) in power systems, technical problems arise in both distribution and transmission system level. Voltage rise is the main barrier for connection of DGs in rural areas, while excessive reactive power demand from transmission system is the major concern for Transmission System Operators (TSO). Here, a centralized control scheme based on the Smart Grid is proposed to reduce the impact on the transmission system voltages and improve its stability, while mitigating the voltage rise issue in the distribution network. Reactive power output of DGs, substation capacitors and tap setting of transmission transformer are...
Time-varying acceleration coefficients IPSO for solving dynamic economic dispatch with non-smooth cost function
, Article Energy Conversion and Management ; Volume 56 , 2012 , Pages 175-183 ; 01968904 (ISSN) ; Rabiee, A ; Ehsan, M ; Sharif University of Technology
2012
Abstract
The objective of the dynamic economic dispatch (DED) problem is to schedule power generation for the online units for a given time horizon economically, satisfying various operational constraints. Due to the effect of valve-point effects and prohibited operating zones (POZs) in the generating units cost functions, DED problem is a highly non-linear and non-convex optimization problem. The DED problem even may be more complicated if transmission losses and ramp-rate constraints are taken into account. This paper presents a novel and heuristic algorithm to solve DED problem of generating units, by employing time varying acceleration coefficients iteration particle swarm optimization...
Optimized midterm preventive maintenance outage scheduling of thermal generating units
, Article IEEE Transactions on Power Systems ; Volume 27, Issue 3 , 2012 , Pages 1354-1365 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Parvania, M ; Sharif University of Technology
2012
Abstract
This paper addresses the midterm preventive maintenance outage scheduling problem of thermal generating units which is becoming increasingly important due to the aging of power generation fleet. In this context, a novel midterm preventive maintenance outage scheduler is proposed based on decision tree and mixed integer linear formation which explicitly considers the thermal units aging momentum in terms of failure rate. This allows the system operators to determine the thermal units' maintenance outage window based on the cost/benefit analysis of preventive maintenance tasks while optimizing the time interval between consecutive maintenance tasks. Additionally, the division of the year-long...
Optimized sectionalizing switch placement strategy in distribution systems
, Article IEEE Transactions on Power Delivery ; Volume 27, Issue 1 , 2012 , Pages 362-370 ; 08858977 (ISSN) ; Fotuhi Firuzabad, M ; Parvania, M ; Mosleh, M ; Sharif University of Technology
2012
Abstract
Automation is acknowledged by distribution utilities as a successful investment strategy to enhance reliability and operation efficiency. However, practical approaches that can handle the complex decision-making process faced by decision makers to justify the long-term financial effects of distribution automation have remained scarce. An automated and remote-controlled sectionalizing switch play a fundamental role in an automated distribution network. This paper introduces a new optimization approach for distribution automation in terms of automated and remotely controlled sectionalizing switch placement. Mixed-integer linear programming (MILP) is utilized to model the problem. The proposed...
Role of fiber arrangements in operation of a double-fiber opto-mechanical system
, Article Journal of Applied Sciences ; Volume 11, Issue 16 , 2011 , Pages 3001-3007 ; 18125654 (ISSN) ; Golnabi, H ; Sharif University of Technology
2011
Abstract
Determination of the surface structure using the light reflection is an important issue. The aim is to study such surface reflections using an opto-mechanical system. The effects of the fiber arrangements in the operation of an opto-pair probe system for surface profiling are described. The opto-mechanical testing system consists of a double-fiber optical probe design and an electro-mechanical scanning system. Reflection signals for the plane and cylindrical surfaces made with different curvatures and materials are investigated with both probes and the results are compared. The reflection signal for the plane surface is independent of the double-fiber orientation in probe but for the curves...
Impacts of service quality regulation on distribution automation investment
, Article 2011 10th International Conference on Environment and Electrical Engineering, EEEIC.EU 2011 - Conference Proceedings, 8 May 2011 through 11 May 2011 ; May , 2011 , Page(s): 1 - 4 ; 9781424487820 (ISBN) ; Fotuhi Firuzabad, M ; Mohammadnezhad Shourkaei, H ; Sharif University of Technology
2011
Abstract
This paper investigates the effects of service quality regulation on investing in distribution automation. Among different regulatory instruments for quality regulation, the Reward-Penalty Scheme (RPS) has been selected to evaluate the effect of monetary incentive on behavior of Electric Distribution Utility (EDU) for service reliability. By implementing different automation strategies, the value of enhancing reliability indices and consequently the value of rewards and penalties are calculated for each strategy. For achieving to more realistic outcome, ten years horizon is considered. Furthermore, in the calculation of reliability indices, the time varying failure rate of components is...
Optimal placement of PMUs to maintain network observability using a modified BPSO algorithm
, Article International Journal of Electrical Power and Energy Systems ; Volume 33, Issue 1 , January , 2011 , Pages 28-34 ; 01420615 (ISSN) ; Ranjbar, A. M ; Amraee, T ; Mozafari, B ; Sharif University of Technology
2011
Abstract
This paper presents a novel approach to optimal placement of Phasor Measurement Units (PMUs) for state estimation. At first, an optimal measurement set is determined to achieve full network observability during normal conditions, i.e. no PMU failure or transmission line outage. Then, in order to consider contingency conditions, the derived scheme in normal conditions is modified to maintain network observability after any PMU loss or a single transmission line outage. Observability analysis is carried out using topological observability rules. A new rule is added that can decrease the number of required PMUs for complete system observability. A modified Binary Particle Swarm Optimization...
Optimal placement and sizing of distributed resources for congestion management considering cost/benefit analysis
, Article IEEE PES General Meeting, PES 2010, 25 July 2010 through 29 July 2010, Minneapolis, MN ; 2010 ; 9781424483570 (ISBN) ; Abbaspour Tehrani Fard, A ; Rashidinejad, M ; Lee, K. Y ; Sharif University of Technology
2010
Abstract
Congestion management is one of the most important issues for secure and reliable system operations in deregulated electricity market. This paper presents a cost/worth analysis approach for optimal location and sizing of Distributed Resources (DRs) to mitigate congestion and increase security of the system. In order to reduce the solution space a priority of candidate buses is formed, then optimal location and sizing problem is discussed. To increase the accuracy of results, load duration curve is constituted and based on this curve different load levels are incorporated into this study. Proposed method considers economical factors such as congestion rent, deferred upgrading investment and...
Strategy deviation index as a new reactive market power indicator
, Article IET Conference Publications, 7 November 2010 through 10 November 2010, Agia Napa ; Volume 2010, Issue 572 CP , 2010 ; 9781849193191 (ISBN) ; Nourizadeh, S ; Ranjbar, A. M ; Sharif University of Technology
2010
Abstract
Reactive market power assessment is an important issue for ISOs and the regulators of the reactive power market. Due to the localized characteristics of reactive power as a technical support and its monopsonistic nature as an economic commodity, a vivid reactive market power index including market share, demand side and cost is not achieved yet. In this paper, a new reactive market power index is presented which is based on bidding strategy deviation of the GENCOs after establishing a uniform price auction reactive market. Not knowing others' offers to ISO, each unit faces a bidding strategy problem that is solved using game theory. Considering its production costs, the unit uses the...