Search results for "PV systems"
showing 10 items of 19 documents
Performance Evaluation of a Three- Phase Five-Level Quasi-Z-Source Cascaded H-Bridge for Grid-Connected Applications
2018
In the field of the PV generation, Quasi-Z-source cascaded H-bridge (qZS-CHB) inverters are promising due to their features of modularity and high voltage conversion ratio. Thus, new topology structures and innovative modulation techniques are continuously being developed to improve the performance in terms of voltage stress and harmonic content. This paper proposes an innovative modulation technique that allows reducing the voltage stress and a specially designed grid-connected control strategy is also introduced. Through simulations in MATLAB, it has been validated that the performance of a three-phase five-level qZS-CHB is improved with the proposed solution.
Characterization of DC series arc faults in PV systems based on current low frequency spectral analysis
2021
Abstract This work presents an experimental study focused on the characterization of series arc faults in direct current (DC) photovoltaic (PV) systems. The aim of the study is to identify some relevant characteristics of arcing current, which can be obtained by means of low frequency spectral analysis of current signal. On field tests have been carried out on a real PV system, in accordance with some tests requirements of UL 1699B Standard for protection devices against PV DC arc faults. Arcing and non-arcing current signals are acquired and compared and the behavior of a set of indicators proposed by authors is analyzed. Different measurement equipment have been used, in order to study th…
Development of a big data bank for PV monitoring data, analysis and simulation in COST Action 'PEARL PV'
2019
COST Action entitled PEARL PV aims at analyzing data of monitored PV systems installed all over Europe to quantitatively evaluate the long-term performance and reliability of these PV systems. For this purpose, a data bank is being implemented that can contain vast amounts of data, which will enable systematic performance analyses in combination with simulations. This paper presents the development process of this data bank.
Modified Modulation Techniques for Quasi-Z-Source Cascaded H-Bridge Inverters
2018
Quasi-Z-source cascaded H-bridge (q Z S - C H B) inverters are one promising solution for high power photovoltaic (PV) systems. This type of topologies inherits the advantages of cascaded converters (i.e., multilevel outputs) and impedance-source inverters (i.e., high conversion ratios). In addition, it allows increasing the inverter reliability (with high redundancy). However, the modulation and control of qZS-CHB inverters are challenging to a certain extent. Thus, this paper proposes modified modulation techniques to increase the performances of qZS-CHB converters in terms of voltage gains and stresses. The novelty lies in the use of the switching frequency optimal as reference signals i…
The new course of FITs mechanism for PV systems in Italy: novelties, strong points and criticalities
2011
The paper deals with the new course of the Feed-in Tariffs mechanism for photovoltaic systems that will start from January 1, 2011 in Italy with the actuation of the Government Decree DM 06/08/2010. After a short introduction on Feed-in Tariffs and Net-metering in Italy, the paper focuses the attention on an economical comparison between the incentives established by the Government Decree DM 19/02/07, ended on December 31, 2010 and those introduced by the DM 06/08/2010. The economical comparison is based on three indexes: the Pay Back Period, the Net Present Value and the Internal Rate of Return, characterizing the investments done for the realization of the photovoltaic systems. In particu…
Optimization of photovoltaic energy production through an efficient switching matrix
2013
This work presents a preliminary study on the implementation of a new system for power output maximization of photovoltaic generators under non-homogeneous conditions. The study evaluates the performance of an efficient switching matrix and the relevant automatic reconfiguration control algorithms. The switching matrix is installed between the PV generator and the inverter, allowing a large number of possible module configurations. PV generator, switching matrix and the intelligent controller have been simulated in Simulink. The proposed reconfiguration system improved the energy extracted by the PV generator under non-uniform solar irradiation conditions. Short calculation times of the pro…
Review of the energy and economic parameters involved in the effectiveness of grid-connected PV systems installed in multi-storey buildings
2014
Abstract The assessment of PV energy in an urban context is extremely complex because many factors have to be considered. Moreover, when the purpose is calculating the realistic amount of the electricity demand of a city that can be covered by the photovoltaic generation, it is necessary to estimate the number of photovoltaic systems whose installation is economically advantageous. Such a topic requires an economic analysis, which is affected by the number of energy and economic parameters involved and the values assigned to them to perform calculations. Some parameters are perfectly known and unvarying, like the paid incentives. Adversely, some parameters, like the efficiency degradation o…
Design of Photovoltaic System for Rural Electrification in Rwanda
2017
Master's thesis Renewable Energy ENE500 - University of Agder 2017 In this century of accelerated development in various domains, some African countries are still facing a challenge of lack of power due to its scarce in some places, where by the main source of power (generation of electricity) is hydro since thermal and fuel are still on a small scale. This problem results in less productivity and economic decline of some countries like Rwanda which is among African countries that are at a very high speed in development, the grid lines from distant places are stack and they are few compared to the need of electricity in all corners of the country, especially in rural areas whereby each hous…
REVIEW OF GUIDELINES FOR PV SYSTEMS PERFORMANCE AND DEGRADATIONS MONITORING
2018
35th European Photovoltaic Solar Energy Conference and Exhibition; 2037-2050
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…