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electromechanical-modes
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Sensitivity-based generators redispatch to improve electromechanical mode damping considering transmission lines resistance
, Article 27th Iranian Conference on Electrical Engineering, ICEE 2019, 30 April 2019 through 2 May 2019 ; 2019 , Pages 491-496 ; 9781728115085 (ISBN) ; Parniani, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
This paper proposes a novel formula to calculate sensitivities of electromechanical modes to generators active power changes. Quadratic eigenvalue problem is applied to construct the framework of the proposed formula. Sensitivity factors are calculated using power system model parameters and power flow variables, which can be either obtained via state estimation or measured directly by phasor measurement units. The 39-bus New England power system is used to verify performance of the proposed method
Estimation of Power System Electromechanical Dynamics by Processing Ambient Data Measured by PMUs
, M.Sc. Thesis Sharif University of Technology ; Parniani, Mostafa (Supervisor)
Abstract
In recent years, the architecture of power systems has evolved in such a way to ease the use of Wide Area Measurement Systems (WAMS) to monitor real time situation of the grid. One of the most prevalent approaches for monitoring power systems is using data gained from Phasor Measurement Units (PMUs) and implementing advanced signal processing algorithms. By this way, tracking the electromechanical oscillatory modes of systems and stability evaluation become attainable. Unlike the model-based methods of estimating electromechanical modes, in which non-linear differential equations are linearized around the operation point, measurement-based methods lead to more accurate and continuously...
Interaction of the dynamics of doubly fed wind generators with power system electromechanical oscillations
, Article IET Renewable Power Generation ; Volume 7, Issue 2 , March , 2013 , Pages 89-97 ; 17521416 (ISSN) ; Ranjbar, A. M ; Sharif University of Technology
2013
Abstract
The interaction of the dynamics of doubly fed wind generators with the electromechanical mode of nearby synchronous generators (SGs) can affect the small signal stability of power systems with high penetration levels of wind power. In this study, a novel approach is developed to investigate these interactions and their impact on the damping of power system oscillations. In this approach it is not necessary to model the dynamic behaviour of system SGs and only the frequencies of system oscillations are important. This approach is based on the sensitivity of SGs electromechanical eigenvalue with respect to variations in the Jacobian matrix of power system. By applying this approach to a test...
Novel approaches for online modal estimation of power systems using PMUs data contaminated with outliers
, Article Electric Power Systems Research ; Volume 124 , July , 2015 , Pages 74-84 ; 03787796 (ISSN) ; Hatami, M ; Parniani, M ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
One of the most important issues in modal estimation of power systems using PMUs data is the negative effect of outliers. Hence, in addition to the techniques of analyzing PMUs data, the necessity of implementing some kinds of approach to overcome these outliers is tangible. This paper aims to present different approaches to overcome outliers and also estimate the electromechanical modes of the system accurately when there is suspicion that the PMUs data may be contaminated by discordant measurements. Proposed approaches are generally categorized into two main classifications: the first category detects and modifies outliers in the pre-processing stage adaptively and then prepares the...
Different approaches for estimation of dampings and frequencies of electromechanical modes from PMU ambient data
, Article 2015 IEEE 15th International Conference on Environment and Electrical Engineering, EEEIC 2015 - Conference Proceedings, 10 June 2015 through 13 June 2015 ; June , 2015 , Pages 1748-1753 ; 9781479979936 (ISBN) ; Hatami, M ; Parniani, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Small signal stability of power systems is one of the most crucially important issues, since the electrical demand is increasing at a galloping rate and power systems are expanding day by day. In this regard, estimation of dampings and frequencies of electromechanical modes through the analysis of field measurements has become a heated study topic for electrical power system researchers in recent years. There have been several methods to analyze different types of Phasor Measurement Units (PMUs) signals i.e., transient, ambient, and probing. Among the proposed techniques, those which are capable of analyzing ambient data seems to be more practical, since this type of data can be achieved...
Damping Critical Electromechanical Oscillations in Power System Through Remedial Actions Using Wide Area Measurement System (WAMS)
, Ph.D. Dissertation Sharif University of Technology ; Parniani, Mostafa (Supervisor) ; Aminifar, Farrokh (Co-Supervisor)
Abstract
Nowadays, by proliferation the basis of the phasor-based synchronous wide area measurement system (WAMS), its application for improving electromechanical oscillations damping has been considered by researchers. In interconnected power systems, inter-area modes are usually critical modes. There are two approaches for damping these modes by utilizing WAMS: 1) the traditional approach of using power system stabilizers with wide area signals; and 2) discrete corrective actions by changing the operating conditions. The first approach requires a thorough study at the design stage, installation and testing. Besides, the controller is designed for a specific operating point. Nevertheless, in the...
Ambient data-based online electromechanical mode estimation by error-feedback lattice RLS filter
, Article IEEE Transactions on Power Systems ; 2017 ; 08858950 (ISSN) ; Parniani, M ; Aminifar, F ; Sharif University of Technology
Abstract
This paper proposes a novel error-feedback lattice recursive least-squares (EF-LRLS) filter for online estimation of power system oscillatory modes. The EF-LRLS filter is applied to ambient data provided by phasor measurement units to identify the autoregressive (AR) model parameters. This filter has a modular structure; accordingly, if the length of the filter equals N, it identifies AR(1) to AR(N) models concurrently. In the proposed method, removing very low and high frequencies and re-sampling steps are fulfilled in an online fashion. This adaptive filter has less computational complexity than standard RLS filter, making it an appropriate choice for online system identification. The...
An analytic methodology to determine generators redispatch for proactive damping of critical electromechanical oscillations
, Article International Journal of Electrical Power and Energy Systems ; Volume 123 , 2020 ; Parniani, M ; Aminifar, F ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
This paper presents a model-based method for applying online proactive generators redispatch to improve damping of the critical electromechanical oscillations of power system. The proposed method comprises two stages: 1) monitoring modal characteristics of oscillatory modes in ambient condition, and 2) applying generators redispatch based on sensitivities of the critical mode to the generators active power changes using a new analytic method. An online identification method such as error feedback lattice recursive least square adaptive filter is applied for online estimation of the oscillatory modes. Then, whenever the damping ratio of an identified mode is less than a preset threshold, its...