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2019, SpringerBriefs in Energy
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7 pages
1 file
The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.
2021
One of the fundamental concerns in the operation of modern power systems is the assessment of their frequency stability in case of inertia-reduction induced by the large share of power electronic interfaced resources. Within this context, the paper proposes a framework that, by making use of linear models of the frequency response of different types of power plants, including also grid-forming and grid-following converters, is capable to infer a numerically tractable dynamical model to be used in frequency stability assessment. Furthermore, the proposed framework makes use of models defined in a way such that their parameters can be inferred from real-time measurements feeding a classical least squares estimator. The paper validates the proposed framework using a full-replica of the dynamical model of the IEEE 39 bus system simulated in a real-time platform.
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590), 2004
Mathematical model for studying electric power system (EPS) frequency changes is developed. The model gives user an estimation of the weighted average frequency of the entire electric power system during time range of primary control. In paper are presented effects of changing some model parameters on system frequency behavior.
ArXiv, 2017
The increasing penetration of non-synchronous renewable energy sources (NS-RES) alters the dynamic characteristic, and consequently, the frequency behaviour of a power system. To accurately identify these changing trends and address them in a systematic way, it is necessary to assess a large number of scenarios. Given this, we propose a frequency stability assessment framework based on a time-series approach that facilitates the analysis of a large number of future power system scenarios. We use this framework to assess the frequency stability of the Australian future power system by considering a large number of future scenarios and sensitivity of different parameters. By doing this, we identify a maximum non-synchronous instantaneous penetration range from the frequency stability point of view. Further, to reduce the detrimental impacts of high NS-RES penetration on system frequency stability, a dynamic inertia constraint is derived and incorporated in the market dispatch model. T...
Electrical Power systems are going through a transition of increasing penetration of Renewable Energy
E3S Web of Conferences, 2020
Application of the frequency scan method for the determination of resonant conditions in a transmission power grid requires great effort since the harmonic power system simulation model needs to be developed. This process is rather complicated since the original model used for fundamental frequency load-flow analysis is built with respect to certain assumptions and, thus, intolerable errors are introduced when frequency-domain properties of the power system are investigated. To strike a balance between inputs needed for the development of such model (time, data amounts) and accuracy of the results, it is proposed to employ a method which makes it possible to represent dead-end, double-ended and tapped 110-220 kV substations as a single frequency-dependent equivalent so that the harmonic power system model is reduced. Such an element essentially is a series R-L or R-L-C shunt, parameters of which vary with frequency. The algorithm for the evaluation of its parameters is proposed and ...
IEEE Transactions on Power Systems, 2022
In many power systems, the increased penetration of inverter-based renewable generation will cause a decrease in kinetic energy storage, leading to higher frequency excursions after a power disturbance. This is the case of the future Nordic Power System (NPS). The look-ahead study reported in this paper shows that the chosen units participating in Frequency Containment Reserves (FCR) cannot keep the frequency above the prescribed threshold following the outage of the largest plant. This analysis relies on a detailed model of the Northern European grid. The latter is compared to the classical single-mass equivalent, and the impact of voltage-dependent loads is assessed in some detail. Next, the paper focuses on emergency power control of the HVDC links that connect the NPS to the rest of the European grid, which can supplement or even replace part of the FCR. The proper tuning of that control is discussed. Finally, the analysis is extended to the HVDC links connecting the future North Sea Wind Power Hub under two configurations, namely low and zero inertia. The impact of outages in the latter subsystem is also assessed. The material to simulate the system with industrial software is made publicly available. Index Terms-Frequency containment reserves, hvdc frequency support, nordic power system, north sea wind power hub. I. INTRODUCTION T HE continuous drive to reduce carbon emissions and meet the climate agreement goals is reshaping power systems all over the world. Amongst many factors, the large-scale integration of inverter-based generation and the increasing interconnection capacity, contribute the most in phasing out conventional power plants, thereby decreasing power system kinetic energy storage. With lower inertia, the frequency response to power imbalances worsens, challenging Transmission System
Journal of Control, Automation and Electrical Systems, 2014
Currently, there is a lack of standard methodology to characterize frequency responses of electric power grids for power line communication purpose. As a result, fair comparisons among measurement campaigns carried out in different parts of the world are missing. Aiming at to deal with this issue, this contribution discusses a complete soundingbased methodology to estimate frequency responses of electric power grids combining sampling frequency offset error estimation and correction, timing synchronization, channel estimation, and channel estimation enhancement techniques. The effectiveness of this methodology is validated by using well-known power line channel models, as well as measured ones, covering the frequency band from 1.7 up to 50 MHz. The attained results show that the methodology provides estimates in shorten period of time in comparison with the network analyzer based methodology and because of that it is capable of characterizing the periodically and time-varying behavior of electric power grids. Additionally, it is shown that the methodology can be successfully applied to characterize frequency responses of electric equipment and, as a conse
2018 Workshop on Modeling and Simulation of Cyber-Physical Energy Systems (MSCPES), 2018
The deployment of variable renewable energy based power plants is increasing all over the world, however, unlike conventional power plants these are mostly connected to the grid via power electronic interfaces. High penetration of power electronic interfaced generation (PEIG) has an important impact on the inertia of the system, which is of major concern for frequency and large disturbance rotor angle (transient) stability. Therefore, it is desirable to study the effectiveness of widely used approaches to assess the stability of a system with high penetration of PEIG. This paper concerns with the modelling and control aspects of a power system for the evaluation of the most widely used metrics (indicators) to assess the dynamics of the power system related to frequency and rotor angle stability. The functionalities of Python are used to automate the generation of operational scenarios, the execution of time domain simulations, and the extraction of signal records to compute the aforesaid indicators. The paper also provides a discussion about possible improvements in the application of these indicators in monitoring tasks.
IEEE Access, 2020
The transition from power systems dominated by synchronous machines to systems based on converter-based generation technologies (CGTs), is weakening currently robust power systems by reducing system inertia with the replacement of synchronous generators with low-inertia CGTs. From a frequency stability viewpoint, this is resulting in faster frequency dynamics and more frequent and larger frequency excursions after system contingencies, thus significantly affecting the stability of power systems dominated by CGTs, requiring detailed stability assessments to ensure the secure integration of CGTs. In this paper, a practical framework is presented for frequency stability studies based on time domain simulations of power systems with CGTs. A fundamental part of the proposed approach is the use of a filter to first identify worst-case scenarios among various possible system operating conditions. Once these worst-case scenarios are identified, a clustering technique is used to select representative worst-case operating conditions to evaluate the frequency stability of the system using time-domain simulations. The effectiveness of the proposed framework is demonstrated on the Chilean Northern Interconnected System (NIS), where it is shown that the proposed filter is able to quickly identify worst-case scenarios for further study. Moreover, we show that the selected representative operating conditions cover a wide-range of worst-case frequency responses, demonstrating the effectiveness of the proposed tool for frequency stability analyses.
Comunicación y Medios, 2011
En 1999 apareció la primera edición de El consumo cultural en América Latina, que a partir de un conjunto de artículos provenientes de diferentes autores y disciplinas buscaba dar cuenta de las principales tendencias teóricas y líneas de investigación desplegadas en la región sobre los procesos de comunicación y transformaciones culturales. Un aspecto novedoso del libro era el acento en las audiencias y sus modos de interpelar, releer, disolver o resistir los mensajes emitidos por los diferentes medios. El libro, coordinado por Guillermo Sunkel, fue celebrado por estudiosos de la comunicación e investigadores interesados en los estudios culturales que encontraron allí una interesante selección de investigaciones realizadas en diferentes países del continente a los cuales era difícil acceder dada su dispersión. Esto convirtió al libro en un referente obligado de los estudiantes de comunicación que accedieron así a artículos de conocidos autores como Jesús Martín-Barbero, Guillermo Orozco, Néstor García Canclini, María Cristina Mata, entre otros. Siete años después aparece esta segunda edición de "El consumo cultural en América Latina". Se trata de una versión revisada y ampliada, que conserva el núcleo central de la compilación anterior y su misma organización en cuatro partes: Aproximaciones teórico metodológicas, usos y prácticas de consumo cultural, apropiación del arte y el patrimonio y consumo de medios; a la cual se han agregado siete nuevos artículos que dan cuenta de nuevos procesos comunicacionales y de consumo cultural que han irrumpido en América Latina en estos años. La "puesta al día" implicó también la revisión de los artículos por parte de sus autores. El capítulo sobre el consumo de medios, que presenta las mayores modificaciones, fue enriquecido con artículos referidos al cine e Internet, los cuales se agregaron a prensa, radio y televisión. Además se incluyó a los niños como receptores de la televisión. Un aspecto destacable de esta compilación es que da cuenta de la heterogeneidad de aproximaciones al tema del consumo cultural, tanto en lo referido a lo teórico como al modo de abordar metodológicamente las investigaciones; lo que hace manifiesto el que pese a los avances hay un desafío abierto. Como señala Guillermo Sunkel "Desafío teórico porque no existe un modelo capaz de describir y explicar los procesos de conusmo cultural, los que son regulados por muy diversas racionalidades: económicas, políticas y simbólicas. Desafío metodológico pues no existe una modalidad privilegiada para abordarlo en la investigación empírica".
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