Search results for " Power system measurement"
showing 10 items of 21 documents
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…
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.
Development of a high-accuracy PC-based wattmeter with commercial data acquisition boards
2011
This paper presents the development of a high accuracy sampling wattmeter, which makes use of two commercial data acquisition boards (DAQs) connected to a common personal computer. Commercial software is also used for data processing and implementation of the virtual instrument. The set up of the PC-based wattmeter is described and a preliminary evaluation of its metrological performances is made by means of two series of experimental tests, which were carried out with an electric power standard and a high performance multifunction calibrator. © 2011 IEEE.
A PC-based wattmeter for accurate measurements in sinusoidal and distorted conditions: Setup and experimental characterization
2012
This paper presents the development of a high-accuracy sampling wattmeter, which can be employed with both sinusoidal and distorted input signals. The proposed personal computer (PC)-based system is a simple, portable, and low-cost solution because it is based on two commercial data acquisition boards connected to a common PC. Owing to this solution, the voltage is sensed directly, avoiding expensive voltage dividers, while the current is sensed by means of a noninductive current shunt. Commercial software is also used for data processing and implementation of the virtual instrument. The setup of the PC-based wattmeter is described, with a detailed description of the correction strategy of …
Arc Fault Detection Method Based on CZT Low-Frequency Harmonic Current Analysis
2017
This paper presents a method for the detection of series arc faults in electrical circuits, which has been developed starting from an experimental characterization of the arc fault phenomenon and an arcing current study in several test conditions. Starting from this, the authors have found that is it possible to suitably detect arc faults by means of a high-resolution low-frequency harmonic analysis of current signal, based on chirp zeta transform, and a proper set of indicators. The proposed method effectiveness is shown by means of experimental tests, which were carried in both arcing and nonarcing conditions and in the presence of different loads, chosen according to the UL 1699 standard…
Narrowband power line communications for medium voltage smart grids
2014
The aim of the paper is to show how narrowband power line communications (NB-PLCs) can be a valid solution for medium voltage grids. Advantages and drawbacks of this solution are analyzed, starting from some experimental communication results, which were carried out on the medium power system networks of the islands of Ustica and Favignana, in the presence of the net voltage. Furthermore, some communication architectures and hardware prototypes based on NB-PLCs are proposed for different smart grids applications.
Measurement uncertainty impact on simplified load flow analysis in MV smart grids
2018
This work is focused on the measurement uncertainty impact on load flow analysis in medium voltage (MV) distribution networks. In more detail, the paper presents the uncertainty evaluation of a simplified load flow algorithm, which is based on the load power measurements at each secondary substation and one voltage measurement at the slack bus (i.e. the voltage at the MV bus bars of the primary substation). To reduce the costs of the monitoring system, the load flow algorithm makes use of LV load power measurements for all the substations except those of MV users, where MV transducers are usually already installed. The uncertainties on the algorithm input quantities (load powers and slack b…
A prototypal architecture of a IEEE 21451 network for smart grid applications based on power line communications
2015
This paper deals with the development of reliable measurement and communication devices and systems and their integration on a prototypal network architecture for smart grid applications, based on the use of narrowband power line communications (PLCs). The proposed solution is presented and discussed in the framework of the ISO/IEC/IEEE 21451 family of Standards. Currently, PLCs are not properly addressed by the aforesaid Standards; on the other hand, by including such issue, their guidelines could represent a common platform for the integration and interoperability of the proposed systems and devices. This would allow to exploit the benefits of the IEEE 21451 approach also for PLC-based sm…
A self-synchronizing instrument for harmonic sources detection in power systems
2004
The deregulation of energy markets holds out new prospects for contract between customers and utilities, in which the price of energy can depend on voltage quality and load characteristics, as well as on the responsibility for disturbances caused to supply voltage in power systems. In this context, harmonic sources detection is one of the main problems, because of equipment sensibility and the proliferation of loads which absorb non-sinusoidal currents. In this paper the authors present a new instrument based on a time domain method for the detection of harmonic active powers in three-phase systems, which can be usefully applied even in the presence of unbalance or asymmetry. The amplitude …