Search results for "PV"
showing 10 items of 704 documents
An international perspective on hospitalized patients with viral community-acquired pneumonia
2019
Background Who should be tested for viruses in patients with community acquired pneumonia (CAP), prevalence and risk factors for viral CAP are still debated. We evaluated the frequency of viral testing, virus prevalence, risk factors and treatment coverage with oseltamivir in patients admitted for CAP. Methods Secondary analysis of GLIMP, an international, multicenter, point-prevalence study of hospitalized adults with CAP. Testing frequency, prevalence of viral CAP and treatment with oseltamivir were assessed among patients who underwent a viral swab. Univariate and multivariate analysis was used to evaluate risk factors. Results 553 (14.9%) patients with CAP underwent nasal swab. Viral CA…
EVALUATING THE FACTORS AFFECTING THE BREAK-EVEN COST OF ON-SITE PV GENERATION AT INDUSTRIAL UNITS
2017
33rd European Photovoltaic Solar Energy Conference and Exhibition; 2870-2874
REVIEW OF GUIDELINES FOR PV SYSTEMS PERFORMANCE AND DEGRADATIONS MONITORING
2018
35th European Photovoltaic Solar Energy Conference and Exhibition; 2037-2050
The use of two-diode substitute model in predicting the efficiency of PV conversion in low solar conditions
2017
The article presents theoretical foundations of a two-diode equivalent model of a photovoltaic cell/module (PV), together with calculation procedures. A physical interpretation of individual components of an equivalent model was presented. Its practical application in predicting efficiency of operation of various PV cells and modules in low insulation conditions was demonstrated. The obtained predictions were verified with the actual results of their operation in open space (outdoor). The practical suitability of the “model” in early detection of ageing phenomena, such as, for example, absorber degradation taking place in PV modules, was demonstrated. The article was prepared on the basis o…
Application of the reduced I-V Blaesser’s characteristics in predicting PV modules and cells conversion efficiency in medium and high insolation cond…
2017
The article presents theoretical foundations of application of the reduced I-V Blaesser’s characteristics in predicting a photovoltaic cell/module (PV) efficiency, together with calculation procedures. A detailed analysis of the error of this transformation method of characteristics was carried out. Its practical application in predicting efficiency of operation of various PV cells and modules in medium and high insulation conditions was demonstrated. The practical suitability of the presented method in early detection of ageing phenomena, such as, for example, absorber degradation taking place in PV modules, was demonstrated. The article was prepared on the basis of the results of testing …
Technical and economical comparison between different topologies of PV plant under mismatch effect
2014
This paper presents a technical and economical comparative analysis between two topology of photovoltaic plant. In particular the performances of series-parallel (SP) and total cross tied (TCT), topologies are taken into account, referring to a partially shaded photovoltaic plant. Thanks to a simulation model developed, in the paper the mismatch effects due to three different shading conditions, for SP and TCT topology plant, are quantified. Since the TCT solution, even though increase the energy production, raise the complexity of plants as well as their costs, an evaluation of the individual costs of each component of a SP and TCT plant topology, as PV modules, support structure, inverter…
The assessment of EU photovoltaic trend by using PCA and DEA techniques
2012
Aim of this work is, firstly, to produce a synthetic indicator able to identify the main factors that allowed the Photovoltaic (“PV” since now) diffusion from 1996 (PV wide diffusion starting date) to 2010, in 14 selected countries (on the basis of the best performance at EU level, showed by the time series considered) and, secondly, we want to evaluate the technical efficiency of these countries in terms of efficient resources utilization and cost efficiency. For this scope a two steps analysis is performed. In the first step, by using the Principal Component Analysis (PCA) technique, we will identify specific weights of the variables considered for each year, and the roles (in terms of we…
Economic and technical feasibility of a photovoltaic system in university building
2009
The use of renewable sources for electric power production can compensate the ever increasing energy demand in buildings. This article shows a study on the feasibility – both from the economic and technical point of view, of a photovoltaic system to be built on the premises of a university faculty. After a historical analysis on the building’s consumption – both on a yearly and monthly base, which highlights the need for an autonomous electric power production system, the difficult task of the technical optimization was undertaken with the aim of minimizing the impact or visual interference of the plant. A series of simulations allowed estimating the right compromise between producibility o…
DC series arc faults in PV systems. Detection methods and experimental characterization
2020
This work is focused on the arc faults phenomenon in DC photovoltaic (PV) systems. The paper gives an overview of arc detection methods proposed in literature and presents a preliminary experimental characterization of the arcing current, focusing the attention on series arcs, whose detection is particularly challenging. Experimental tests are carried out, both in laboratory and on field, in order to investigate some relevant characteristics in the arcing current, which can be feasible for the arc detection purpose. Both arcing and non-arcing current signals are acquired and compared in both time and frequency domain. On-field measurements are carried out on a real photovoltaic system, in a…
Simulation and experimental validation of multicarrier PWM techniques for three-phase five-level cascaded H-bridge with FPGA controller
2017
The FPGA represents a valid solution for the design and implementation of control systems for inverters adopted in many fields of power electronics because of its high flexibility of use. This paper presents an overview and an experimental validation of the MC SPWM techniques for a three-phase, five-level, cascaded H-Bridge inverter with FPGA controller-based. Several control algorithms are here implemented by means of the VHDL programming language and the output voltage waveforms obtained from the main PWM techniques are compared in terms of THD%. Simulation and experimental results are analyzed, compared and discussed.