937 resultados para power distribution control
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El artículo analiza la figura del prosumidor desde los estudios visuales a partir de la combinación de la teoría de los actos de habla y los nuevos medios. El objetivo es evaluar si la distinción entre productores y consumidores, estrategias y tácticas de Michel de Certeau continúa siendo operativa en las interfaces gráficas de la cultura global de la información de Scott Lash. Para ello distingue dos tipos de performatividad de los actos de habla: la performatividad top-down del software, y la bottom-up de los juegos del lenguaje y las formas de vida. Estos tipos se aplican al análisis del discurso de los eslóganes que aparecen en los sitios web de las iniciativas “open” y de economía colaborativa, ya que las primeras están dedicadas a la producción de bienes inmateriales y las segundas a la producción de bienes materiales. El desarrollo muestra cómo los dos tipos de performatividad transforman el análisis textual de los estudios literarios y cinematográficos en una metodología capaz de investigar acciones materiales, humanas y no humanas. Las conclusiones describen el surgimiento de nuevas convenciones narrativas de poder y control ajenas a la ficción que apuntan a una “DIY society”.
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Este artículo estudia el impacto que la asimetría de información tiene sobre el mercado eléctrico no regulado colombiano desde una perspectiva teórica esta -- Se analizan los tratamientos que se han hecho en los principales mercados eléctricos internacionales para solucionar esta imperfección de mercado y, a la vez, analiza los resultados obtenidos, donde a partir de las experiencias se proporciona recomendaciones al mercado de energía colombiano -- También se analiza la Resolución CREG 035 de 2015 y el cambio que las modificaciones en esta traen para el funcionamiento del sector -- Los resultados obtenidos basados en las experiencias internacionales y la teoría económica indican que el mercado eléctrico colombiano está experimentando un problema de información asimétrica y esta nueva Resolución no ayuda a mitigarlo
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This work presents the development and modification of techniques to reduce the effects of load variation and mains frequency deviation in repetitive controllers applied to active power filters. To minimize the effects of aperiodic signals resulting from the connection or disconnection of non-linear loads is developed a technique which recognizes linear and nonlinear loads, and operates to reset the controller only when the error due to the transition of considerable value, and the transition is from non-linear to linear load. An algorithm to adapt the gain of the repetitive controller, based on a sigmoid function adaptation, in order to minimize the effects caused by random noise in the measurement system is also used. This work also analyzes the effects of frequency variation and presents the main methods to cope with this situation. Some solutions are the change in the number of samples per period and the variation of the sampling rate. The first has the advantage of using linear design techniques and results in a time invariant system. The second method changes the sampling frequency and leads to a time variant system that demands a difficult analysis of stability. The proposed algorithms were tested using the methods of truncation of the number of samples and the method of changing the sampling rate of the system to compensate possible frequency variations of the grid. Experimental results are presented to validate the proposal.
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Power generation from alternative sources is at present the subject of numerous research and development in science and industry. Wind energy stands out in this scenario as one of the most prominent alternative in the generation of electricity, by its numerous advantages. In research works, computer reproduction and experimental behavior of a wind turbine are very suitable tools for the development and study of new technologies and the use of wind potential of a given region. These tools generally are desired to include simulation of mechanical and electrical parameters that directly affect the energy conversion. This work presents the energy conversion process in wind systems for power generation, in order to develop a tool for wind turbine emulation testing experimental, using LabVIEW® software. The purpose of this tool is to emulate the torque developed in an axis wind turbine. The physical setup consists of a three phase induction motor and a permanent magnet synchronous generator, which are evaluated under different wind speed conditions. This tool has the objective to be flexible to other laboratory arrangements, and can be used in other wind power generation structures in real time. A modeling of the wind power system is presented, from the turbine to the electrical generator. A simulation tool is developed using Matlab/Simulink® with the purpose to pre-validate the experiment setup. Finally, the design is implemented in a laboratory setup.
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The focus of this research is to explore the applications of the finite difference formulation based on the latency insertion method (LIM) to the analysis of circuit interconnects. Special attention is devoted to addressing the issues that arise in very large networks such as on-chip signal and power distribution networks. We demonstrate that the LIM has the power and flexibility to handle various types of analysis required at different stages of circuit design. The LIM is particularly suitable for simulations of very large scale linear networks and can significantly outperform conventional circuit solvers (such as SPICE).
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Tämän työn tavoitteena on skenaarioiden avulla luoda pitkän aikavälin alueellinen sähkökuormien kehitysennuste Rovaniemen Verkko Oy:lle. Pitkän aikavälin kuormitusennusteet ovat välttämättömiä verkon kehittämisen pohjalle, jotta verkko voidaan mitoittaa vastaamaan kuormitusta pitkälle tulevaisuuteen tekniset ja taloudelliset vaatimukset huomioiden. Kuormitusennusteen onkin jatkossa tarkoitus toimia apuvälineenä verkon strategisessa kehittämisessä. Pohjana kuormitusennusteissa on tilastokeskuksen ja Rovaniemen kaupungin väestö- ja työpaikkaennusteet. Väestöennusteiden ja erilaisten rakentamistilastoiden avulla arvioidaan uudisrakentamisen määrä tulevaisuudessa. Uudisrakentamisen kuormitusvaikutuksiin päästään työssä määritettyjen paikallisten ja rakennustyyppikohtaisten sähkön ominaiskulutuksien avulla. Kuormituksien alueellinen sijoittautuminen arvioidaan kaavoituksen ja kaupungin maankäytön toteuttamisohjelman avulla. Työssä tutkitaan myös tulevaisuudessa sähkönkäytössä tapahtuvien useiden muutosten vaikutusta alueelliseen kuormitukseen. Näitä muutoksia ovat muun muassa sähköautojen, hajautetun tuotannon, lämpöpumppujen ja kysynnän jouston lisääntyminen. Myös rakennusten jatkuvasti parantuva energiatehokkuus aiheuttaa muutoksia sähkön kulutukseen.
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Este relatório de estágio representa o desenvolvimento de uma metodologia, com recurso a Tecnologias de Informação Geográfica, que permite a identificação de zonas que condicionam os processos de planeamento, projecto e manutenção das estruturas que compõem a Rede de Distribuição de Energia Eléctrica. Centra-se assim nas Tecnologias de Informação Geográfica enquanto instrumentos que permitem realizar estudos de carácter territorial com relevância para o sector energético. São trabalhadas a identificação e delimitação de zonas de gelo, zonas de poluição industrial e zonas de salinidade em Portugal Continental. A delimitação destas zonas foi realizada com recurso a ferramentas de análise espacial, utilizando dados fidedignos provenientes de Instituições da Administração Pública. São documentadas também tarefas extraordinárias propostas pela EDP Distribuição - Energia, S.A. Desta forma é possível compreender as vantagens e desvantagens da utilização destas tecnologias por parte da EDP Distribuição, de forma a melhorar a gestão dos recursos disponíveis, para ajudar a manter a qualidade do serviço prestado. Ficou no entanto a recomendação de uma maior aposta nestas tecnologias.
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Direito, Programa de Pós-Graduação em Direito, 2016.
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This study took place at one of the intercultural universities (IUs) of Mexico that serve primarily indigenous students. The IUs are pioneers in higher education despite their numerous challenges (Bertely, 1998; Dietz, 2008; Pineda & Landorf, 2010; Schmelkes, 2009). To overcome educational inequalities among their students (Ahuja, Berumen, Casillas, Crispín, Delgado et al., 2004; Schmelkes, 2009), the IUs have embraced performance-based assessment (PBA; Casillas & Santini, 2006). PBA allows a shared model of power and control related to learning and evaluation (Anderson, 1998). While conducting a review on PBA strategies of the IUs, the researcher did not find a PBA instrument with valid and reliable estimates. The purpose of this study was to develop a process to create a PBA instrument, an analytic general rubric, with acceptable validity and reliability estimates to assess students’ attainment of competencies in one of the IU’s majors, Intercultural Development Management. The Human Capabilities Approach (HCA) was the theoretical framework and a sequential mixed method (Creswell, 2003; Teddlie & Tashakkori, 2009) was the research design. IU participants created a rubric during two focus groups, and seven Spanish-speaking professors in Mexico and the US piloted using students’ research projects. The evidence that demonstrates the attainment of competencies at the IU is a complex set of actual, potential and/or desired performances or achievements, also conceptualized as “functional capabilities” (FCs; Walker, 2008), that can be used to develop a rubric. Results indicate that the rubric’s validity and reliability estimates reached acceptable estimates of 80% agreement, surpassing minimum requirements (Newman, Newman, & Newman, 2011). Implications for practice involve the use of PBA within a formative assessment framework, and dynamic inclusion of constituencies. Recommendations for further research include introducing this study’s instrument-development process to other IUs, conducting parallel mixed design studies exploring the intersection between HCA and assessment, and conducting a case study exploring assessment in intercultural settings. Education articulated through the HCA empowers students (Unterhalter & Brighouse, 2007; Walker, 2008). This study aimed to contribute to the quality of student learning assessment at the IUs by providing a participatory process to develop a PBA instrument.
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This thesis examines the development of state-narco networks in post-transition Bolivia. Mainstream discourses of drugs tend to undertheorise such relationships, holding illicit economies, weak states and violence as synergistic phenomena. Such assumptions fail to capture the nuanced relations that emerge between the state and the drug trade in different contexts, their underlying logics and diverse effects. As an understudied case, Bolivia offers novel insights into these dynamics. Bolivian military authoritarian governments (1964-1982), for example, integrated drug rents into clientelistic systems of governance, helping to establish factional coalitions and reinforce regime authority. Following democratic transition in 1982 and the escalation of US counterdrug efforts, these stable modes of exchange between the state and the coca-cocaine economy fragmented. Bolivia, though, continued to experience lower levels of drug-related violence than its Andean neighbours, and sustained democratisation despite being a major drug producer. Focusing on the introduction of the Andean Initiative (1989-1993), I explore state-narco interactions during this period of flux: from authoritarianism to (formal) democracy, and from Cold War to Drug War. As such, the thesis transcends the conventional analyses of the drugs literature and orthodox readings of Latin American narco-violence, providing insights into the relationship between illicit economies and democratic transition, the regional role of the US, and the (unintended) consequences of drug policy interventions. I utilise a mixed methods approach to offer discrete perspectives on the object of study. Drawing on documentary and secondary sources, I argue that state-narco networks were interwoven with Bolivia’s post-transition political settlement. Uneven democratisation ensured pockets of informalism, as clientelistic and authoritarian practices continued. This included police and military autonomy, and tolerance of drug corruption within both institutions. Non-enforcement of democratic norms of accountability and transparency was linked to the maintenance of fragile political equilibrium. Interviews with key US and Bolivian elite actors also revealed differing interpretations of state-narco interactions. These exposed competing agendas, and were folded into alternative paradigms and narratives of the ‘war on drugs’. The extension of US Drug War goals and the targeting of ‘corrupt’ local power structures, clashed with local ambivalence towards the drug trade, opposition to destabilising, ‘Colombianised’ policies and the claimed ‘democratising mission’ of the Bolivian government. In contrasting these US and Bolivian accounts, the thesis shows how real and perceived state-narco webs were understood and navigated by different actors in distinct ways. ‘Drug corruption’ held significance beyond simple economic transaction or institutional failure. Contestation around state-narco interactions was enmeshed in US-Bolivian relations of power and control.
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This research activity aims at providing a reliable estimation of particular state variables or parameters concerning the dynamics and performance optimization of a MotoGP-class motorcycle, integrating the classical model-based approach with new methodologies involving artificial intelligence. The first topic of the research focuses on the estimation of the thermal behavior of the MotoGP carbon braking system. Numerical tools are developed to assess the instantaneous surface temperature distribution in the motorcycle's front brake discs. Within this application other important brake parameters are identified using Kalman filters, such as the disc convection coefficient and the power distribution in the disc-pads contact region. Subsequently, a physical model of the brake is built to estimate the instantaneous braking torque. However, the results obtained with this approach are highly limited by the knowledge of the friction coefficient (μ) between the disc rotor and the pads. Since the value of μ is a highly nonlinear function of many variables (namely temperature, pressure and angular velocity of the disc), an analytical model for the friction coefficient estimation appears impractical to establish. To overcome this challenge, an innovative hybrid solution is implemented, combining the benefit of artificial intelligence (AI) with classical model-based approach. Indeed, the disc temperature estimated through the thermal model previously implemented is processed by a machine learning algorithm that outputs the actual value of the friction coefficient thus improving the braking torque computation performed by the physical model of the brake. Finally, the last topic of this research activity regards the development of an AI algorithm to estimate the current sideslip angle of the motorcycle's front tire. While a single-track motorcycle kinematic model and IMU accelerometer signals theoretically enable sideslip calculation, the presence of accelerometer noise leads to a significant drift over time. To address this issue, a long short-term memory (LSTM) network is implemented.
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In a smart grid environment, attention should be paid not only to the power supplied to satisfy loads and system losses but also to the services necessary to provide security and stability to the system: the so-called ancillary services. As they are well known the benefits that distributed generation can bring to electrical systems and to the environment, in this work the possibility that active power reserve for frequency control could be provided by distributed generators (DGs) in an efficient and economical way is explored. The proposed methodology was tested using the IEEE 34-bus distribution test system. The results show improvements in the capacity of the system for this ancillary service and decrease in system losses and payments of the distribution system operator to the DGs.
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By Dewey Anderson, executive secretary.
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This paper presents a system to control the power injected by a photovoltaic (PV) plant on the receiving network. This control is intended to mitigate some of the negative impacts that these units may produce on such networks, while increasing the installed power of the plant. The controlled parameters are the maximum allowed value of injected active power and the corresponding power factor, whose setpoints values may be fixed or dynamic. The developed system allows a local and a remote control. The injected power and the corresponding power factor may be set by following a predetermined profile or by real time adjustments to fulfill specific operation constraints on the receiving network. The system acts by adjusting the control parameters on the PV inverters. The main goal of the system is, in the end, to control the PV plant, ensuring the accomplishment of technical constraints and, at the same time, maximizing the installed power of the PV plant, which may be an important issue concerning the economic performance of such plants