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stability-constraints
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Allocating the cost of transient stability constraint relief in bilateral electricity markets
, Article IET Generation, Transmission and Distribution ; Volume 5, Issue 11 , 2011 , Pages 1124-1131 ; 17518687 (ISSN) ; Feuillet, R ; Ehsan, M ; Hadj-Saied, N ; Sharif University of Technology
2011
Abstract
In this study, the issue of allocating the cost of transient stability relief in a bilateral electricity market is investigated. The results of a constrained generation scheduling problem can be utilised in two ways to price the cost of a constraint. In the first method, which is the basis of nodal pricing, the Lagrange multipliers of the nodal power balance constraint are used as the price of electricity at various buses. In the second method, which is used in this study, the constraint relief scheme is based on a bid-based adjustment market of increments and decrements offered by generators to be involved in the constraint relief process. In the scheme used in this study, the cost of...
A mathematical model for acceleration phase of aerodynamically alleviated catamarans and minimizing the time needed to reach final speed
, Article Journal of Marine Science and Technology (Japan) ; Volume 21, Issue 3 , 2016 , Pages 458-470 ; 09484280 (ISSN) ; Mehdigholi, H ; Seif, M. S ; Sharif University of Technology
Springer-Verlag Tokyo
Abstract
Racing catamarans use aerodynamic alleviation concept which in existing extreme ground effect significantly enhances the performance. Beside design measures, controlling strategies may be employed as convenient solutions to improve the performance and address concerns regarding poor stability in these crafts. Being of substantial importance for a racing catamaran to reach the final speed as soon as possible, this study attempts to find the optimal form of changing the drive angle (as control variable) to minimize its acceleration time. In this regard, a mathematical model is developed for forward acceleration phase of these catamarans based on empirical and theoretical methods. Then the...
Effect of considering stability requirements on antagonistic muscle activities using a musculoskeletal model of the human lumbar spine
, Article 2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013 ; 2013 , Pages 260-264 ; Nickpour, H ; Arjmand, N ; Farahmand, F ; Sharif University of Technology
2013
Abstract
The recruitment pattern of trunk muscles is determined using a three-dimensional model of the spine with two joints and six symmetric pairs of muscles in which both equilibrium and stability requirements are satisfied. Model predictions are verified using Anybody Modeling System (AMS) and Abaqus. The model is used to test the hypothesis that antagonistic muscle activities are necessary for the spinal stability. The model with stability constraints predicts muscle activities greater than those predicted without stability consideration. In agreement with experimental data, the stability-based model predicts antagonistic muscle activities. It is shown that spinal stability increases with trunk...
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...
An approach to optimal dispatch of bilateral electricity contracts regarding voltage stability
, Article IFAC Proceedings Volumes (IFAC-PapersOnline) ; Volume 5, Issue PART 1 , 2006 , Pages 65-70 ; 14746670 (ISSN); 9783902661081 (ISBN) ; Ranjbar, A. M ; Mozafari, A ; Amraee, T ; Sharif University of Technology
IFAC Secretariat
2006
Abstract
This paper proposes a methodology for optimal dispatch of bilateral electricity contracts, which may endanger the system voltage stability in light of short-term operational planning of a deregulated power system. In this framework the value that each owner of a transaction is willing to pay will reflect how much the electricity contract is important to be implemented physically. The proposed model dispatches optimally the bilateral transactions regarding the prices offered by owners of bilateral contracts for reactive power and transmission capacity utilization in one hand and, the total operational costs of reactive power resources in the other hand. The model also includes the limits...