Search results for "medium voltage"
showing 10 items of 12 documents
Realizzazione di un banco di misura e di un modello in Simulink per la ricerca e la caratterizzazione di reti di accoppiamento per la trasmissione di…
2010
Power Line Communication in Medium Voltage Systems: Characterization of MV Cables
2008
The aim of this paper is to illustrate the development of a theoretical and experimental study on the characterization of medium voltage (MV) cables in the frequency range 25-200 kHz. Two transmission line configurations, line-ground and line-line, were considered in order to evaluate the main parameters, such as the characteristic impedance and the attenuation constant alpha. A simplified model of the line-ground configuration is proposed which allows one to evaluate the characteristic impedance and the attenuation constant by means of geometrical dimensions. The model was verified by experimental measurements on commonly used MV cables, RG7H1R, with an aluminium core of different sections…
An Experimental Characterization of Time of Arrival Accuracy for Time Synchronization of Medium Voltage Smart Grid Solutions
2019
The time synchronization of smart grid devices is a critical feature for the successful application of advanced grid monitoring and control techniques. Synchronization mechanisms based on the accurate estimation of the Time of Arrival (ToA) of network messages - sent over power line cables - are a promising solution to achieve synchronization tasks over distribution lines. In this paper, a chirp-based synchronization technique over the Medium Voltage (MV) grid has been proposed and characterized. Such approach has the benefit of not requiring the installation of a dedicated infrastructure, thanks to the exploitation of power distribution lines for the transmission of time synchronization da…
Simulation of a Power Line Communication System in Medium and Low Voltage Distribution Networks
2011
The aim of the paper is to study the influence of the power transformer on signal transmission in the case of a power line communication (PLC) system in a overhead Medium Voltage (MV) power network. A model of the PLC system was carried out by means of the Simulink® software. A distributed parameter MV overhead line, two power transformers, the signal coupling networks and the receiving and transmitting line coupling interface of a ST7540 FSK powerline transceiver were included in the model. The performances of the complete PLC communication system are evaluated for different line lengths by means of the attenuation computed as ratio between the received and transmitted voltage signals.
“Coupling interfaces for communication transceivers over power lines”
2010
Model of line to shield power line communication system on a Medium Voltage network
2010
In this paper a complete model of a power line communication (PLC) system on a Medium Voltage (MV) network is presented in the case of a line-ground configuration. A simple and friendly Simulink (R) software is used to develop the model. A distributed parameter MV cable model in line-ground configuration is considered together with the power transformers, the signal coupling networks and the receiving and transmitting line coupling interface of a ST7540 FSK powerline transceiver. The performances of the complete PLC communication system are evaluated for different line lengths by means of the attenuation computed as ratio between the received and transmitted voltage signals.
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
Four-Level Three-Phase Inverter With Reduced Component Count for Low and Medium Voltage Applications
2021
This paper proposes a novel three-phase topology with a reduced component count for low- and medium-voltage systems. It requires three bidirectional switches and twelve unidirectional switches for producing four-level voltages without using flying capacitors or clamping diodes, reducing the size, cost, and losses. Removing flying capacitors and clamping diodes allows it to simplify control algorithms and increase the reliability, efficiency, and lifetime. A modified low-frequency modulation (LFM) scheme is developed and implemented on the proposed topology to produce a staircase voltage with four steps. Further, a level-shifted pulse width modulation (LSPWM) is used to reduce the filter siz…
Power-Line Communication in Medium-Voltage System: Simulation Model and Onfield Experimental Tests
2012
The aim of this paper is to develop a complete model of a power-line communication (PLC) system operating on a medium-voltage (MV) network. The core-shield configuration was chosen for signal transmission in the power cables. In order to validate the developed model experimental, the medium-voltage network of the Favignana island was used to carry out detailed testing. The transmission was performed between two transformer substations in the presence of mains voltage (i.e., 24 kV). ST7540 FSK power-line transceivers, together with capacitive coupling interfaces, were used for the transmission and the reception of the communication signal. The correlation between the experimental measurement…
Design of a Time Dissemination System Using Chirp Modulation for Medium Voltage Smart Grid Applications
2020
The monitoring and the management of smart grid require an advanced communication infrastructure. The time synchronization is among the most important services such an infrastructure should offer. Several solutions are available to disseminate the time information in a distributed system; for instance, most of the times a global positioning system (GPS) receiver is used to recover accurate time information. However, GPS receivers need a clear view of the sky. Other solutions, like the use of a network-based synchronization mechanism, require a dedicated communication infrastructure, which is not always feasible for economical reason. Thus, the use of the power grid itself to disseminate a t…