Search results for "Volt"
showing 10 items of 2187 documents
Technical, Environmental and Economical Aspects of Hybrid Systems Including Renewables and Fuel Cells
2006
In this paper, some configurations including renewables and fuel cells are studied. Technical, environmental and economical aspects are treated in the frame of the EU regulations concerning the ‘emission trading’ issue and the way in which Italy has implemented the relevant EU directive. The study has been carried out considering some architectures including renewables such as photovoltaic and wind with a back up system to increase continuity of supply based on the application of fuel cells and of a hydrogen storage system. Performing several runs with different values of the cost of energy (COE) bought from the network and produced with traditional fuel, it has been observed that, for some…
A DC-DC power converter for PV module characterization
2014
In this paper, a standard-compliant electronic load setup for PV module curve detection which features high accuracy, low cost and components count is proposed. The proposed device is based on a DC-DC power converter in open-loop configuration. The proposed system is designed according to regulation constraints in order to achieve high performances in curve detection. Design criteria are discussed. The model is implemented in PSIM environment. Simulation based on data input of a commercial PV Conergy E215P module are carried out under several environmental conditions to show the accuracy of the proposed electronic load. Simulation results are reported.
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…
Dynamics photovoltaic generators: Technical aspects and economical valuation
2010
The strategy adopted from many European nations and not, to entrust the electric energy production to differently energetic sources has determined an increment of the scientific research for the solar resource exploitation. These scientific community activities follows with attention from the entrepreneurial world have concentrated on the innovative techniques and methodologies of the source conversion, solar concentration and the direction's device optimization. This job focuses its attention on the simple application of solar-track device, based on consolidated technologies. The diffused application of these dispositive, could be, shortly, an important increment of electricity generation …
Implementation and experimental validation of a real-time PWM algorithm based on B-Spline carriers for three phase voltage source inverters
2009
This paper presents the implementation and experimental results of an algebraic real-time sinusoidal pulse width modulation algorithm (SPWM) based on B-Spline carriers. B-spline functions are used as carrier signals with the aim to to reduce harmonic content of the three phase inverter output voltage. The presented algorithm eliminates the problem of B-spline recursive evaluation with convolution integrals or convolution sums in digital counterpart. The pulse pattern synthesis is made with the help pre-calculated duty cycle expressions. In this way there is no real need to synthesize the carrier signal so the hardware and the whole inverter control system becomes cheaper, more reliable and …
Optimized Topology for High Efficiency Battery Discharge Regulator
2008
In the following years power levels of 20 kW to 50 kW will be demanded by the telecommunication satellites. It is not possible to keep 0.5 kW modules with up to 100 modules in parallel and, therefore, higher power modules must be used. A higher bus voltage seems also necessary and any voltage below 150 V and above 100 V could meet the needs. In addition, new optimized topologies that process only a part of the total power delivery can be employed to improve the efficiency. In this article, design guidelines and experimental results of a high efficiency battery discharge regulator (BDR) module based on parallel power processing are given.
Uncertainty evaluation of a Backward/Forward Load Flow algorithm for a MV smart grid
2015
This paper presents the uncertainty evaluation of an innovative measurement algorithm for load flow analysis in MV distribution networks. The measurement procedure is based on Low Voltage (LV) load power measurements applied on a Backward/Forward (B/F) algorithm for the Load Flow (LF) resolution. Furthermore, in the procedure a three phase voltage measurement at the MV generating substation bus-bars is also considered. The accuracy analysis of the LF algorithm is performed in the case of a real load condition in the distribution grid of Ustica island, Italy. The analysis takes into account the uncertainty of the measurement instruments at the LV side of each secondary substation power trans…
A statistic approach of cables ageing in MV lines on thermal and electrical combined stress
2006
The paper introduces a methodology that through a probabilistic characterisation of load for MV network, and implementing a life model for combined electric and thermal stresses, simulates the process of ageing of the insulating materials evaluating the expected life time of the cable. Such evaluation is necessary to the possibility of assuming less restrictive thermal overloading limits on electrical cables, with the consequential increase on reserve that cables could offer. A numerical example is reported to better explain the methodology
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.