Search results for "Photovoltaic power system"
showing 10 items of 42 documents
Charging management of grid integrated battery for overcoming the intermittency of RE sources
2016
Grid integration of distributed generation (DG) systems with energy storage system can help not only in increasing the more penetration of DG systems into the network but it is also going to help in improving the power system dynamics, stability and control as well as helping in demand side management. In this work, a method for integrating an energy storage with the grid which can provide the prescribed active and reactive power to the grid is presented. The main objective is to ensure a high state of charge (SOC) of the battery with the innovative control system for taking part in power system control. Active and reactive power dispatching using a bi-directional DC-DC converters and a vol…
Harmonic mitigation of a grid-connected photovoltaic system using shunt active filter
2017
Conventional LC filters cannot compensate effectively harmonics due to non-linear loads in a grid-connected photovoltaic (PV) system. Thus, active power filters (APF) are introduced due to its characteristics and performances, for compensation of harmonics from non-linear loads in the grid-connected photovoltaic (PV) system. This work presents a three-phase voltage-fed shunt active power filter implementation to mitigate the harmonics in which the filter control system focuses on generating reference source current for compensating harmonic effects from non-linear loads. Furthermore, the developed model is verified with an experimental data from a nonlinear load.
An economic study about the installation of PV plants reconfiguration systems in Italy
2014
This paper shows the economic convenience of the application of a reconfiguration system for photovoltaic plants, considering the incentives system in Italy and its recent modifications. The reconfiguration is an alternative to the Distributed Maximum Power Point Tracking, DMPPT, technique used to overcome the mismatch problem in Photovoltaic, PV, plants. The reconfiguration techniques employ a microprocessor-based system that modifies the layout of the PV plant by physically changing the connections among modules. After the explanation of the working principle of the PV reconfiguration system allowing the improvement of the efficiency of the same plant and the relevant installation, the ma…
Reconfiguration Techniques of Partial Shaded PV Systems for the Maximization of Electrical Energy Production
2007
In this paper, the research of the optimal layout of photovoltaic (PV) modules in a PV array giving the maximum output power under different shaded working conditions is carried out. The particular condition of non uniform solar exposition of the modules is analyzed. The study of the different configurations has been carried out starting from a circuital model used for the design of PV cells and for the simulation of the working behavior of PV arrays. The attained results appear to be interesting although the complexity of the problem in mathematical terms is huge when the number of panels is high. Moreover, the results confirm that this approach often allows to attain a higher electrical e…
Higher PV Module Efficiency by a Novel CBS Bypass
2011
There is an increasing focus on reducing costs and improving efficiency for photovoltaic (PV) cells and modules as well as finding a more efficient approach to the product manufacturing. This letter introduces an innovative solution to bypass shaded PV cells instead of a traditional Schottky diode, in order to avoid overheating of cells in the case of partial shading. The goal is to reduce the power dissipation and improve the general efficiency of a PV generator. A novel device called cool bypass switch is then presented. It is made up of a Power MOS driven by a controller with the task to charge a storage capacitor. Tests and comparisons with standard Schottky diodes are then performed an…
Numerical Analysis of Medium Scale PV Plants and Their Power-Flow Control System With a Simple Three Phase Inverter
2012
This paper presents a mathematical analysis of a medium scale Photovoltaic (PV) power generation system connected to the distribution network and of its control system, in which the conversion stage is unique thanks to the absence of a boost chopper. Boost choppers are usually used as actuator for maximum power point tracking (MPPT). The conducted analysis leads to the conclusion that the used inverter presents two degrees of freedom that can be easily exploited in a control system in which the inverter simultaneously realizes the interconnection to the grid and at the same time realizes the MPPT control. The structure of the control system is then presented, discussed and then validated by…
Survey on power increase of power by employment of PV reconfigurator
2015
This paper shows the performance of a PV system under shadow projection on PV panels. The reconfiguration techniques, employing a microprocessor-based system, modifies the layout of the PV plant by physically changing the connections among modules, in order to recover the loss of power due to the shadows. Different cases have been considered to evaluate the increase of power.
Distribution grid analysys through PSAT open source tools
2015
In this paper a study of an electrical distribution grid with presence of renewable energy sources performed using the Power System Analysis Tool is presented. The paper describes the load flow analysis of a real existing grid owned by the Italian DSO “ENEL Distribuzione SpA” and located in an urban area.
A New Device for the Control and the Connection to the Grid of Combined RES-based Generators and Electric Storage Systems
2013
In this paper a new device for the control and the connection to the supply utility grid of combined RES-based generators and electric storage systems is presented. The device is a bidirectional converter that can be controlled so as to facilitate the interface between the low voltage grid and photovoltaic or wind generators combined with batteries, contemporary addressing the requirements of the reference technical standards for users connection and providing different ancillary services. In the paper the functioning of the device and its circuit diagram are described, the single parts are shown and the potentiality of its control system are commented. © 2013 IEEE.
Load mismatch of grid-connected photovoltaic systems: Review of the effects and analysis in an urban context
2013
Abstract The mismatch between generated and consumed electricity is a relevant topic of the energy and economic assessment of photovoltaic (PV) systems. Due to the load mismatch some amount of PV electricity may be exported to the grid because the electrical demand is temporarily lower than production, whereas a consumption, which is higher than production and/or that does not match the available PV generation, will require to be supplemented by the public grid electricity. The presence of the load mismatch can cause the effect of disadvantageously purchasing electricity from the grid and/or squandering the unexploited PV energy. If only a very small part of the PV generation is used to sup…