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Security-constrained unit commitment with integration of battery storage in wind power plant
, Article 2017 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2017, 23 April 2017 through 26 April 2017 ; 2017 ; 9781538628904 (ISBN) ; Hajibandeh, N ; Ehsan, M ; Soleymani, S ; Sharif University of Technology
Abstract
There is a global tendency towards using Distributed Generation (DG) and renewable energy resources. Considering low utilization cost and low undesirable environmental effects, wind farms have become a considerable resource for producing electrical energy in many countries. Since Wind farms are not programmable and their power output which depends on weather and wind speed is uncertain, they create problems for utilizing electricity system. There are different methods for preserving system stability against the uncertainty of wind power plants. Optimal utilization of pumped storage and gas resources is one of the approaches for reducing production risk of wind farms. In this paper, it is...
Profit-based unit commitment of integrated CHP-thermal-heat only units in energy and spinning reserve markets with considerations for environmental CO2 emission cost and valve-point effects
, Article Energy ; Volume 133 , 2017 , Pages 621-635 ; 03605442 (ISSN) ; Ardehali, M. M ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
For the purposes of lowering environmental emission cost and increasing economic profit, energy efficient combined heat and power (CHP) units can be integrated with conventional separate heat and power production units to meet heat and power demands. The goal of this study is to develop and examine a novel heuristic and deterministic optimization algorithm for solving the profit-based unit commitment (PBUC) problem for a generation company with integrated CHP-thermal-heat only system for (i) satisfying demands for heat and power, (ii) selling spinning reserve for power, (iii) reducing environmental CO2 emission cost, and (iv) accounting for valve-point effects for steam turbines. For...
Risk-Based networked-constrained unit commitment considering correlated power system uncertainties
, Article IEEE Transactions on Smart Grid ; Volume 11, Issue 2 , 2020 , Pages 1781-1791 ; Pourahmadi, F ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
The forecast errors for distributed energy resources (DERs) and hourly demands have contributed to power system uncertainties and additional risks in the day-ahead scheduling of electricity markets. In this paper, a risk-based approach is introduced to determine the stochastic solution of network-constrained unit commitment (NCUC) when additional uncertainties are embedded in the power system scheduling. The historical power market transaction data are used to model nodal injection uncertainties and reserve capacity requirements are considered to assess the solution of the risk-based NCUC. The proposed NCUC problem is formulated as a single-stage second order cone program which is a convex...
Allocation of Operating Reserve to Demand Response Resources in Composite System
, M.Sc. Thesis Sharif University of Technology ; Fotuhi Firuzabad, Mahmoud (Supervisor)
Abstract
Considerable developments in demand-side real-time telemetry systems allow ISOs to use demand-side provided reserves in ancillary service markets. Presently, many ISOs designed programs to utilize the reserve provided by demand response resources in their market, and deploy them in emergency conditions. These programs are called ancillary service demand response (ASDR) programs. This thesis presents a stochastic programming model to schedule reserve provided by demand response resources in load buses of system. The demand-side reserve resources are modeled by demand response providers (DRP) which have the responsibility of aggregating and managing responses of customers. The reserve provided...
Security Constraint Unit Commitment With Wind Power Uncertainty By Stochastic Programming
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hamid (Supervisor)
Abstract
Economic aspects of power systems in their new structures, have been the subject of most of new publications in the area of electrical engineering after the era of restructuring. Nowadays, the power generation business is totally market driven in most of countries all around the world and the system operators are responsible for maintaining a high level of system security as well as the economic operation of the power systems. The development of wind power generation has rapidly progressed over the last decade. With the advancement in wind turbine technology, wind energy has become competitive with other fuel-based resources. The fluctuation of wind, however, makes it difficult to optimize the...
Security Constrained Unit Commitment With Natural Gas Transmission Delivery Constraints
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mahdi (Supervisor)
Abstract
Natural gas power plant installed in power system as rapid start unit. In the recent decades, with increasing in the number of gas generating units in the world, consideration of natural gas transmission network in optimal solution of security-constrained unit commitment (SCUC) become a non-negligible problem. The gas transmission grid constraints integrated into the scheduling of thermal units in the proposed model for minimizes power system operating cost. In a power plant transmission of natural gas to power plant is very important because congestion in natural gas pipeline increases. This model could consider natural gas storage tank in gas transmission network as decision variable....
Coordinated Scheduling of Power and Natural Gas Systems Considering Demand Uncertainty
, M.Sc. Thesis Sharif University of Technology ; Rafiee, Majid (Supervisor)
Abstract
The everyday increasing electricity consumption of household and industrial sectors across the world, and also the limited generation capacity and fuel supplies has led electricity companies, whether in private or government sectors, to focus deliberately on power generation planning, its costs, risks and constraints Because of many reasons including high efficiency, low cost of capital investment, expeditious permitting, and operation flexibility of gas-fired generating units, electricity companies prefer them to old ones like coal-fired or oil-fired generating units. Thus natural gas has gained a significant share in the portfolio of electricity generation fuel resources, and it is...
Management of Different Levels of Frequency Control Reserve Ancillary Services
, M.Sc. Thesis Sharif University of Technology ; Fotuhi Firuzabad, Mahmoud (Supervisor)
Abstract
In most countries Frequency control services as one of the Ancillary services are presented in market scheme. Frequency control are used in different levels to balance generation and demand. Each reserve levels is implemented with specific characteristics and rules. Clearance of energy and one control reserve has some drawbacks so in this thesis we try to clear energy and different reserve levels simultaneously. Each reserve level is determined with special criteria. This criterion in primary reserve is frequency deviation restriction and unit commitment risk in territory reserve that is determined by system operator. In this thesis these two criteria are formulated in linear form and...
Interruptible Load Contracts and Demand Response Program Implementation in Stochastic Long-Term SCUC with Wind Farm Consideration
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Sayyed Hamid (Supervisor)
Abstract
Providing more choices to customers for determining the cost of their required reliability levels is one of the most important targets of restructured power system. Centralized management of reliability in Vertically Integrated Utility (VIU) applying the same policies to different customers is replaced with decentralized management allowing customers to participate in reliability management based on their required reliability levels. In this thesis, impact of emergency demand response programs, interruptible load contract and wind farms on the long-term security constrained unit commitment has been studied. Random outages of generators and transmission lines, load forecast inaccuracies as...
A stochastic security approach to energy and spinning reserve scheduling considering demand response program
, Article Energy ; Volume 36, Issue 5 , 2011 , Pages 3130-3137 ; 03605442 (ISSN) ; Nikzad, M ; Mozafari, B ; Ranjbar, A. M ; Sharif University of Technology
Abstract
In this paper a new algorithm for allocating energy and determining the optimum amount of network active power reserve capacity and the share of generating units and demand side contribution in providing reserve capacity requirements for day-ahead market is presented. In the proposed method, the optimum amount of reserve requirement is determined based on network security set by operator. In this regard, Expected Load Not Supplied (ELNS) is used to evaluate system security in each hour. The proposed method has been implemented over the IEEE 24-bus test system and the results are compared with a deterministic security approach, which considers certain and fixed amount of reserve capacity in...
Security constrained unit commitment with flexibility in natural gas transmission delivery
, Article Journal of Natural Gas Science and Engineering ; Volume 27, Part 2 , November 2015 , 2015 , Pages 632–640 ; 18755100 (ISSN) ; Kazemi, M ; Ehsan, M ; Sharif University of Technology
Elsevier
2015
Abstract
This paper presents a formulation of fuzzy optimization for uncertainties in natural gas in fuel constraints for hourly individual unit and total unit fuel consumptions. Security Constrained Unit Commitment (SCUC) is usually a mixed integer programming and gas load flow has a non-linear equation a genetic algorithm is proposed to solve natural gas transmission network. A fuzzy mixed integer programming optimization is briefly discussed and adapted to deal with security constrained unit commitment schedule. Finally, two case studies are investigated (IEEE 6-bus system with 7-node natural gas transmission grid and the IEEE 118-bus power system linked with 14-node gas transmission test system)...
A novel efficient model for the power flow analysis of power systems
, Article Turkish Journal of Electrical Engineering and Computer Sciences ; Volume 23, Issue 1 , 2015 , Pages 52-66 ; 13000632 (ISSN) ; Fotuhi Firuzabad, M ; Aminifar, F ; Sharif University of Technology
Abstract
The overall system status calculated by pflower flow analysis is the most basic information used for all decisions taken by power system operators and planners. While conventional AC pflower flow solutions are computationally tractable, approximate DC models are employed in many applications, such as optimal power flow studies and unit commitment problems, mainly due to the linear nature of DC models. These models do not provide any information on the reactive power and voltage magnitude quantities and occasionally inaccurate results of the active power values. This paper presents an efficient power flow approach compromising both the con icting aspects of speed and accuracy. The proposed...
A unit commitment for electricity market participation of wind farms
, Article 2017 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2017, 23 April 2017 through 26 April 2017 ; 2017 ; 9781538628904 (ISBN) ; Hosseini, S. H ; Dorostkar Ghamsari, M ; Sharif University of Technology
Abstract
In this paper a reliability, emission, and network security constrained unit commitment (UC) with the focus on wind power integration is formulated. It is shown that clearing both energy and spinning reserve markets taking into account network constraints provides a reliable and economic solution for day-ahead operation planning of a power system with a significant amount of thermal and wind power in the generation portfolio. The developed UC is formulated and implemented in MATLAB. The IEEE 24-Bus Reliability Test System (RTS) is used to verify the UC method by simulation. © 2017 IEEE
Component and mode models for the short-term scheduling of combined-cycle units
, Article IEEE Transactions on Power Systems ; Volume 24, Issue 2 , 2009 , Pages 976-990 ; 08858950 (ISSN) ; Shahidehpour, M ; Li, Z ; Fotuhi Firuzabad, M ; Sharif University of Technology
2009
Abstract
We propose a component model for the scheduling of combined-cycle gas turbine (CCGT) units by mixed-integer programming (MIP) in which combustion turbines (CTs) and steam turbines (STs) are modeled as individual units. The hourly schedule of CCGT based on the component model is compared with that of the mode model. The modeling of modes, which includes a combination of CTs and STs, would require certain approximations for representing fuel input-power output curves, ramping rate limits, minimum operating time limits, etc. The approximations can result in sub-optimal schedules. Furthermore, the commitment and dispatch of CCGTs based on the mode model will require a real-time dispatch to...
Unit commitment with probabilistic spinning reserve and interruptible load considerations
, Article IEEE Transactions on Power Systems ; Volume 24, Issue 1 , 2009 , Pages 388-397 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
2009
Abstract
This paper demonstrates how a probabilistic criterion could be explicitly integrated in the unit commitment (UC) formulation. Both spinning reserve and interruptible load are taken into account as the operating reserve facilities. Incorporating the interruption notice time of interruptible load involves some complexities in the evaluation procedure and problem formulation which is considered in this paper. The expected energy not supplied (EENS) is considered as a probabilistic criterion and a new method is proposed to calculate this index in the presence of interruptible load. The reliability-constrained unit commitment (RCUC) problem is formulated based on the mixed-integer programming...
A novel unit commitment technique considering prohibited operating zones
, Article Journal of Applied Sciences ; Volume 9, Issue 16 , 2009 , Pages 2962-2968 ; 18125654 (ISSN) ; Rashidi Nejad, M ; Abdollahi, A ; Sharif University of Technology
2009
Abstract
The aim of this study is to show the effectiveness of prohibited operating zone. Generation scheduling is a crucial challenge in power systems especially under new environment of liberalization of electricity industry. This study is focused on the economical aspect of unit commitment problem. Since, the generating units may have certain ranges where operation is restricted based upon physical limitations of machine components or instability. Therefore, Prohibited Operating Zones (POZ) as a redundant constraint is considered, while the next load demand as a very important issue is deliberated. In this study generation scheduling of each hour is conducted by considering the next load demands...
Frequency stability improvement in windthermal dominated power grids
, Article IET Generation, Transmission and Distribution ; Volume 14, Issue 4 , 2020 , Pages 619-627 ; Toulabi, M ; Dobakhshari, A. S ; Ranjbar, A. M ; Sharif University of Technology
Institution of Engineering and Technology
2020
Abstract
With the proliferation of intermittent renewable energy sources, power systems need to withstand an increasing number of disturbances that may affect system frequency. In this paper, we focus on the effects of high penetration level of wind turbine-generators (WTG) on the power system operational planning from the frequency point of view. Specifically, an exact formulation for the minimum frequency calculation is presented to increase accuracy and speed of analyses. Then, the effect of WTG's frequency response on the power system frequency stability is investigated to compute the maximum acceptable generation outage as a function of penetration level. Finally, as an application to power...
A modified algorithm for allocating reserve power considering security constraints
, Article International Transactions on Electrical Energy Systems ; Volume 30, Issue 7 , 2020 ; Toulabi, M. R ; Ashouri Zadeh, A ; Ranjbar, A. M ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
This paper addresses a novel formulation and solution for the security constrained reserve management (SCRM) problem in both normal and N − 1 contingency conditions. Indeed, the SCRM problem is a modified version of the security constraint unit commitment problem which is updated with the operational reserve management and frequency stability constraints in both normal and N − 1 contingency conditions. The objective of this problem is to determine the optimal amounts of generation associated with different units and frequency regulation reserve (FRR) and allocate the FRR among the generation units. Therefore, the SCRM problem is a mixed integer nonlinear problem which is solved using the...
A clearing mechanism for joint energy and ancillary services in non-convex markets considering high penetration of renewable energy sources
, Article International Journal of Electrical Power and Energy Systems ; Volume 129 , July , 2021 ; 01420615 (ISSN) ; Rayati, M ; sheikhi, A ; Ranjbar, A. M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This paper introduces a day-ahead clearing model for the simultaneous energy and ancillary services market in high penetration of renewable energy sources (RESs) considering fast-start generators’ behaviors as non-spinning reserve providers. For managing the uncertainties of RESs, the system operator takes the advantages of the stochastic model of security-constrained unit commitment (SCUC) problem considering plausible scenarios. The non-convexities due to the startup costs, minimum power outputs, and commitment variables make the stochastic SCUC problem and market-clearing non-convex. Meanwhile, with traditional market-clearing methods for energy and ancillary services based on marginal...
Reliability-constrained unit commitment using stochastic mixed-integer programming
, Article 2010 IEEE 11th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2010 ; 2010 , p. 200-205 ; ISBN: 9781420000000 ; Fotuhi-Firuzabad, M ; Aminifar, F ; Abiri-Jahromi, A ; Sharif University of Technology
Abstract
This paper proposes a stochastic mixed-integer programming (SMIP) model for the reliability-constrained unit commitment (RCUC) problem. The major objective of the paper is to examine both features of accuracy and efficiency of the proposed SMIP model of RCUC. The spinning reserve of generating units is considered as the only available reserve provision resource; however, the proposed formulation can be readily extended to comprise the other kind of reserve facilities. Expected load not served (ELNS) and loss of load probability (LOLP) are accommodated as the reliability constraints. Binding either or both reliability indices ensures the security of operation incorporating the stochastic...