Search results for " power system"
showing 10 items of 277 documents
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…
Review on photovoltaic based active generator
2015
An active generator has the capacity to support frequency control and instantaneous power balance. The grid operator adjusts the power dispatch of generators according to power demand fluctuations. Photovoltaic (PV) based active generators can be used as load following generators in the same manner as other power dispatch generators. This new type of distribution system, based on active generator(s), needs new innovative management and operation strategies for increasing the penetration of intermittent renewable energy systems. The considered PV based active generator has three units, i.e., PV array, battery storage and super capacitor. In this review paper, the management and operation app…
Experimental evaluation of an hybrid communication system architecture for smart grid applications
2015
In this paper a new communication system architecture is proposed for the development of a SCADA system which can remotely monitor and control intelligent electronic devices (IEDs) connected to the low voltage distribution networks, i.e low voltage smart meter (SM), interface protection devises (IPS). New distributed metering systems and interface devices, together with a proper communication infrastructure (HiperLAN and narrowband power line communication (NB-PLC) on low voltage network), have been developed to allow monitoring the whole power system and controlling the distributed generators of a Smart Grid also in the presence of harmonic distortions. In this way, the electrical energy d…
Techno-economic optimum sizing of hybrid renewable energy system
2013
Using off grid hybrid renewable energy systems for rural electrification has become an attractive solution for those areas, where grid electricity is not feasible or cost of the grid extension is relatively large. Hybrid system combines several energy systems together, therefore it can supply high reliable electricity rather than a PV/battery system or a wind/battery system. But the most important thing is that the system should be economically attractive. To achieve both of these features, each of the components in the hybrid system should be optimally sized. This requires a detailed techno-economic analysis of different possible hybrid system configurations. The objective of this study is…
Medium Voltage Smart Grid: Experimental Analysis of Secondary Substation Narrow Band Power Line Communication
2013
This paper is focused on the possibility of employing narrow band power line communication (PLC) in medium voltage (MV) distribution networks. The topic is investigated by means of both simulations and experimental tests, which were carried out in the distribution network of Ustica Island. In detail, a two-way MV communication was tested between two secondary substations connected by an MV cable power line. Each substation has a by-pass connection at MV bus-bars and an MV/LV oil filled power transformer. In this paper, the MV and the PLC systems under test are described and the experimental tests are presented, which were carried out to evaluate the parameters of the simulation model. The a…
Comparison of power quality impact of different photovoltaic inverters- the viewpoint of the grid
2005
This paper presents the results of an experimental analysis performed with the aim of evaluating the effect of many photovoltaic plants on power quality of the grid. Several parameters as voltage and current distortion, flicker, voltage variations at fundamental frequency and power factor have been observed. The measured values have been compared with the limits reported in the standards and, when possibiIe, their dependence on the characteristics of the grid in terms of its impedance has been pointed out.
Controlled Fault-Tolerant Power Converters for Power Quality Enhancement
2013
Power quality depends generally on the interaction of electrical power with electrical equipments. If electrical equipments operate correctly and reliably without being damaged or stressed, a suitable level of power quality is assured. On the other hand, if the electrical equipment malfunctions, is unreliable, or is damaged during normal usage, power quality is poor and probably the economical loss could be important like the technical one. In the scenario of the Distributed Generation, power quality issues will be moreover important because an higher dissemination of power conditioning equipment will be requested and this obviously increases the sources of vulnerability of the electrical s…
The metrological characterization of the static meters for reactive energy in the presence of harmonic distortion
2007
For the electricity metering for billing purposes in distribution systems, the static meters are substituting the traditional inductive meters. Thus, the evaluation of the performances of such equipments is required, also in the presence of disturbances affecting the power systems. With respect to this, this paper analyzes the main aspects related to the metrological characterization of the static meters for reactive energy in the presence of harmonic distortion. Particular attention is given to the reference standard meters, that are not considered by the actual in-force Standards. The analysis is supported by several experimental tests.
Disturbing Load Detection in Three-Wire and Four-Wire Systems Based on Novel Nonactive Powers From IEEE 1459-2000
2010
This paper presents an enhanced approach for the detection of disturbing loads in distorted and/or unbalanced three-phase power systems, both three-wire and four-wire. It is based on the IEEE Std. 1459-2000 effective apparent power resolution, and it requires only the separation of the fundamental components of voltage and current from the remaining harmonic content. In this paper, the formulation of the novel approach is given, and its effectiveness is discussed by means of several simulation tests, which were carried out on a simple test system.
A virtual instrument for the measurement of IEEE Std 1459-2000 power quantities
2006
In this paper, the authors present a PC-based instrument for the measurement of electrical-power quantities defined in IEEE Std. 1459. The instrument is based on a time-domain technique for the detection of the fundamental and harmonic components of voltages and currents. The time-domain strategy was originally developed by the authors for three-phase, three-wire systems. In that paper, the strategy had been extended to both three-phase, four-wire and single-phase systems. Simulation tests were carried out to assess the uncertainty contribution of the proposed strategy in the absence of the measurement transducers. Moreover, the accuracy of the PC-based instrument with its transducers was e…