Study of a simplified model for DFIG-based wind turbines

In the study of the dynamical behavior of doublyfed induction generators (DFIG), for wind power applications, the use of reduced order models is useful in order to design specific control strategies for wind power plants as well as to obtain lightweight computing simulations. Within this field this paper presents a new dynamic model for wind turbines, based on DFIG, able of representing accurately its behavior during both the steady state and the transient of the grid voltage. As it will be proven this model permits to perform an accurate analysis of the system when there is a voltage dip in the grid. In the following a theoretical study of this model will be carried out and the accuracy of its performance will be tested under different conditions, by means of PSCAD/EMTDC simulations, in order to show its reliability. Finally the reliability of the simplified model will be tested in a scaled experimental setup.Peer ReviewedPostprint (published version

Design and implementation of a modified fourier analysis harmonic current computation technique for power active filters using DSPs

The design and implementation of a harmonic current computation technique based on a modified Fourier analysis, suitable for active power filters incorporating DSPs is presented. The proposed technique is suitable for the monitoring and control of load current harmonics for real-time applications. The derivation of the basic equations based on the proposed technique and the system implementation using the Analogue Devices SHARC processor are presented. The steady state and dynamic performance of the system are evaluated for a range of loading conditions

Compensation algorithms based on the p-q and CPC theories for switching compensators in micro-grids

The main objective of this paper is to com-pare the applicability and p erformance of a switching compensator when it is controlled by algorithms derived from the pq–Theory and from the Current’s Physical Components Power Theory (CPC-Theory) considering a micro-grid application. Compensation characteristics derived from each one of these set of power definitions are highlighted, and simulation results of test cases are shown. Special attention is put on the oscillating instan-taneous real power, as it may produce torque oscillations or frequency variations in weak systems (micro-grids) generators. The oscillating instantaneous real power, as defined in the pq-Theory, gives the amount of energy oscillating between the source and the load, and its com-pensation using a switching compensator must have an energy storage element to exchan ge it with the load. The energy storage element can be ea sily calculated with the pq-Theory

Instantaneous p-q power theory for control of compensators in micro-grids

The main objective of this tutorial is to present the basic concepts on the instantaneous p-q Theory and them show its applicability for controlling switching converters connected in a micro-grid. These converters can be used for connecting renewable energy sources (solar, wind, and others) to the micro-grids or for harmonic, reactive power or unbalance compensation, and even for voltage regulation. The emphasis is given on the compensation characteristics derived from the p-q Theory, and simulation results of test cases are shown. Special attention is put on the oscillating component of the instantaneous real power, as it may produce torque oscillations or frequency variations in weak systems (micro-grids) generators. This oscillating component, as defined in the p-q Theory, gives the amount of oscillating energy between the source and the load, and its compensation through a switching compensator must have an energy storage element to exchange it with the load. With the p-q Theory the energy storage element can be easily calculated as a function of the average component of the instantaneous real power, which depends on the observation period.The authors acknowledge the support from FAPERJ partially for the development of this study and especially for the financial support for the participation in the conference

Actividad antibiofilm de un extracto antibacteriano de schinus fasciculatus y sus componentes

Las bacterias fitopatógenas poseen la capacidad de adherirse y colonizar los tejidos vegetales mediante biofilms. La formación de estas películas bacterianas puede verse afectadas por la presencia de bactericidas en concentraciones sub-letales, algo que sucede comúnmente cuando la aplicación de estos compuestos no es homogénea sobre la superficie de la planta. En este contexto, la actividad antibiofilm de un compuesto antibacteriano podría contribuir al control de enfermedades vegetales que producen grandes pérdidas en los cultivos. En este trabajo se evaluó la capacidad de inhibición de biofilm de un extracto con actividad antimicrobiana de Schinus fasciculatus y sus componentes en concentraciones sub-letales. El extracto foliar fAcet de Schinus fasciculatus y sus componentes, los flavonoides agatisflavona, quercetina, kaempferol se ensayaron en Concentraciones sub-letales previamente establecidas (125-1,9 μg/mL) para determinar su capacidad de inhibir la formación de biofilm de 5 cepas fitopatógenas, Pseudomonas syringae pv tomato Pseudomonas corrugata, Xanthomonas campestris pv vesicatoria, Erwinia carotovora var carotovora y Agrobacterium tumefaciens, mediante el ensayo de cristal violeta en microplaca descripto por O?Toole. Los resultados fueron analizados estadísticamente utilizando los test de Shapiro-Wilk, ANOVA y Kruskal-Wallis del software STATISTICA, version 7. La inhibición de biofilm fue dependiente de la cepa bacteriana, y en menor medida del compuesto ensayado, siendo E. carotovora var. carotovora y A. tumefaciens las más susceptibles, con inhibiciones de entre un 40-80%, mientras que P. corrugata y X. campestres pv vesicatoria fueron las menos susceptibles con una inhibición máxima de un 39%. El extracto y los flavonoides inhibieron en un 40 a 80% la formación de biofilm de las especies bacterianas ensayadas, por lo que en concentraciones sub-letales estos compuestos serían capaces de atenuar la patogenicidad de las bacterias fitopatógenas investigadas.Fil: Terán Baptista, Zareath Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Aredes Fernández, Pedro Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Mandova, T.. Universidad Paris Descartes; FranciaFil: Kritsanida, M.. Universidad Paris Descartes; FranciaFil: Grougnet, R.. Universidad Paris Descartes; FranciaFil: Sampietro, Diego Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaIV Reunión Conjunta de Sociedades de Biología de la República Argentina: nuevas evidencias y cambios de paradigmas en Ciencias BiológicasMendozaArgentinaSociedad de Biología de CórdobaSociedad de Biología de CuyoAsociación de Biología de Tucumá

Control algorithms based on the active and non-active currents for a UPQC without series transformers

This study presents control algorithms for a new unified power quality conditioner (UPQC) without the series transformers that are frequently used to make the insertion of the series converter of the UPQC between the power supply and the load. The behaviour of the proposed UPQC is evaluated in presence of voltage imbalances, as well as under non-sinusoidal voltage-and current conditions. The presented algorithms derive from the concepts involving the active and non-active currents, together with a phase-locked-loop circuit. Based on these real-time algorithms, and considering the proposed hardware topology, the UPQC is able to compensate the harmonic components of the voltages and currents, correct the power factor, and keep the load voltages regulated, all of this in a dynamic way, responding instantaneously to changes in the loads or in the electrical power system. The control algorithms were distributed in a two-DSP digital control architecture, without any communication between them. Consequently, can be increased the sampling frequency of the acquired voltages and currents and improve the UPQC performance. Furthermore, some constraints of the proposed UPQC are evidenced, particularly when the main voltages are imbalanced. Simulation and experimental results are presented to verify the UPQC performance under transient and steady state conditions.info:eu-repo/semantics/publishedVersio

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types