Search results for " modules"
showing 10 items of 59 documents
Photovoltaic plant array reconfiguration: Design of a new device
2014
An efficient strategy to improve unequally irradiated PV plants performances is based on the reconfiguration of the connections between the modules. In this paper, an algorithm, for this purpose conceived, is presented. Moreover, the design, realization and finally also the set up of a new reconfiguration system device is fully shown and discussed. The algorithm conceived simulates several possible series-parallel connections under varying irradiation conditions, and determines the optimal modules connection in order to get the maximum output power. In this way, the reconfiguration system may set up the reconfiguration strategy. The reconfiguration system prototype set up, basically consist…
CIGS PV Module Characteristic Curves Under Chemical Composition and Thickness Variations
2014
This paper analyzes how the electrical characteristics of a CIGS photovoltaic module are affected by the chemical composition and by the thickness variations of the CIGS absorber. The electrical characteristics here considered are the short circuit current, the open circuit voltage, the efficiency and the power peak. The chemical composition is varied by tuning the ratio between gallium and indium. This analysis has been performed by means of the wxAMPS software, developed by the University of Illinois. The above variations have been taken into account on a PV module made of 72 cells. This analysis has been carried out employing a PV module mathematical model developed and implemented by th…
Corrigendum to “A procedure to calculate the five-parameter model of crystalline silicon photovoltaic modules on the basis of the tabular performance…
2014
Only few manufactures provide the wide set of graphical data that are necessary to use high performance predictive tools for PV systems. On the other hand, reliable graphical data require accurate laboratory measurements that increase manufacturing costs. For this reason PV system designers have to choose between the use of cheap PV modules, lacking in technical data, and the reliable energy predictions that are possible only if the current–voltage characteristics are provided by the PV module manufacturers. This paper describes the procedure to evaluate the parameters of a one-diode equivalent circuit able to accurately epresent the electrical behaviour of a PV panel by means of the minimu…
A procedure to calculate the five-parameter model of crystalline silicon photovoltaic modules on the basis of the tabular performance data
2013
Abstract Only few manufactures provide the wide set of graphical data that are necessary to use high performance predictive tools for PV systems. On the other hand, reliable graphical data require accurate laboratory measurements that increase manufacturing costs. For this reason PV system designers have to choose between the use of cheap PV modules, lacking in technical data, and the reliable energy predictions that are possible only if the current–voltage characteristics are provided by the PV module manufacturers. This paper describes the procedure to evaluate the parameters of a one-diode equivalent circuit able to accurately represent the electrical behaviour of a PV panel by means of …
Design, sizing and set up of a specific low cost electronic load for PV modules characterization
2013
In this paper, the design, sizing and set-up of a specific low cost electronic load, based on a DC-DC step-down converter, suitable for the PV module I - V characteristic curves determination, is described. In particular, for its set up, a low cost and user friendly micro-controller has been employed in order to generate the PWM signal. The measures carried out connecting the electronic load prototype to a commercial PV module are here presented and discussed. The conceived electronic load has allowed the determination of 80% of the PV module characteristic curves in 2 s. This low measurement time, lower than the time intervals in which weather conditions may change, allows to assume as con…
Electrical characterization of CIGSSe photovoltaic modules
2017
This work describes the electrical characterization of CIG(S,Se) 2 sub-modules in order to compare the related performances with those obtained from traditional silicon photovoltaic modules. This characterization has been performed through means of a test bench, mainly composed by a solar simulator equipment, allowing the determination of the parameters of the prototypes under test at different irradiances and temperatures.
Integrable systems and moduli spaces of curves
2016
This document has the purpose of presenting in an organic way my research on integrable systems originating from the geometry of moduli spaces of curves, with applications to Gromov-Witten theory and mirror symmetry. The text contains a short introduction to the main ideas and prerequisites of the subject from geometry and mathematical physics, followed by a synthetic review of some of my papers (listed below) starting from my PhD thesis (October 2008), and with some open questions and future developements. My results include: • the triple mirror symmetry among P 1-orbifolds with positive Euler characteristic , the Landau-Ginzburg model with superpotential −xyz + x p + y q + z r with 1 p + …
Moduli spaces of quasitrivial sheaves on the three dimensional projective space
2022
Let M(r,c_1,c_3,c_3) denote the Gieseker--Maruyama moduli space of semistable rank r sheaves on P^3 with the first, second and third Chern classes equal to c_1, c_2 and c_3, respectively. Maruyama proved that the space M(r,c_1,c_3,c_3) is a projective scheme. However, the geometry of such a scheme remains largely unknown, despite the efforts of many authors in the past four decades, and questions about connectedness, irreducibility, the number of irreducible components, and so on, remain open.When r=1 and c_1=0 (which can always be achieved after twisting by an appropriate line bundle), one gets that M(1,0,c_2,c_3) is isomorphic to the Hilbert scheme Hilb^{d,g}(P^3) of 1-dimensional schemes…
Hardware implementation of content based video indexing algorithms
2005
This paper focus on hardware implementation of content based video indexing techniques by using the FPGA technology. We aim to propose hardware modules that can satisfy requirements of constrained applications, such as real time applications and complex applications that can combine a large number of techniques in the same indexing system. We represent tow examples of micro-architectures related to the dominant colors descriptor and the compact color descriptor.
External derivations of internal groupoids
2008
If His a G-crossed module, the set of derivations of Gin H is a monoid under the Whitehead product of derivations. We interpret the Whitehead product using the correspondence between crossed modules and internal groupoids in the category of groups. Working in the general context of internal groupoids in a finitely complete category, we relate derivations to holomorphisms, translations, affine transformations, and to the embedding category of a groupoid. (C) 2007 Elsevier B.V. All rights reserved.