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WO2008000880A1 - Method and system for broadband digital transmission via high and medium voltage networks - Google Patents

Method and system for broadband digital transmission via high and medium voltage networks Download PDF

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Publication number
WO2008000880A1
WO2008000880A1 PCT/ES2007/070106 ES2007070106W WO2008000880A1 WO 2008000880 A1 WO2008000880 A1 WO 2008000880A1 ES 2007070106 W ES2007070106 W ES 2007070106W WO 2008000880 A1 WO2008000880 A1 WO 2008000880A1
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WO
WIPO (PCT)
Prior art keywords
broadband
transmission
digital
modulation
frequency band
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Ceased
Application number
PCT/ES2007/070106
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Spanish (es)
French (fr)
Inventor
José Francisco COMABELLA LÓPEZ
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ENDESA NETWORK FACTORY SL
Original Assignee
ENDESA NETWORK FACTORY SL
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ENDESA NETWORK FACTORY SL filed Critical ENDESA NETWORK FACTORY SL
Publication of WO2008000880A1 publication Critical patent/WO2008000880A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/54—Systems for transmission via power distribution lines
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2602—Signal structure
    • H04L27/2605—Symbol extensions, e.g. Zero Tail, Unique Word [UW]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2203/00—Indexing scheme relating to line transmission systems
    • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
    • H04B2203/5404—Methods of transmitting or receiving signals via power distribution lines
    • H04B2203/5408—Methods of transmitting or receiving signals via power distribution lines using protocols
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2203/00—Indexing scheme relating to line transmission systems
    • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
    • H04B2203/5404—Methods of transmitting or receiving signals via power distribution lines
    • H04B2203/5416—Methods of transmitting or receiving signals via power distribution lines by adding signals to the wave form of the power source

Definitions

  • the present invention relates to a method and digital broadband transmission system using high and medium voltage networks as a transmission channel and applying modern broadband modulation techniques that achieve much higher speed rates than current equipment.
  • the band allocated specifically for communication on high voltage lines is between 40 and 500 kHz and is divided into 4 kHz channels.
  • the modulations used must work in channels that are very affected by noise and be spectrally effective in maintaining the 4 kHz channel.
  • a BLU (Single Side Band) modulation scheme is used, which is a "very simple" modulation - in terms of information transmission capacity. It is used, for example, to modulate a basic telephone channel (3,400 Hz) on which voice and / or data is transmitted using a standard analog modem for telephone band.
  • the process of the invention serves in an optimal way to achieve communications on high and medium voltage power lines with speed rates widely exceeding 64 kbits / s by
  • the invention will use the same frequency band for the data transmission as the one used so far - understood between 40 and 500 kHz.
  • the invention proposes the use of a broadband modulation, typically an OFDM modulation of hundreds of carriers modulated in QAM (quadrature amplitude modulation), requiring high transmission powers.
  • a broadband modulation typically an OFDM modulation of hundreds of carriers modulated in QAM (quadrature amplitude modulation)
  • QAM quadrature amplitude modulation
  • the system of the invention proposes to implement in the network that a series of nodes of broadband data exchange is treated, each of them being constituted by an IP protocol interface, a MODEM of broadband that works in the expected frequency band (40 - 500 kHz), as well as a signal adapter in both amplitude and impedance in the entire frequency band of 40 - 500 kHz.
  • Figure 1 shows a scheme of the system of the invention where two nodes that communicate with each other are represented.
  • the method of the invention serves to transmit data over the high and medium voltage network in broadband in cooperation with the use of modulations of the OFDM type or the like. It comprises the transmission of the information in IP packets with the use of the frequency band between 40 and 500 kHz in cooperation with a broadband modulation and increase in the emission power, and with the logical implementation of a dynamic interference manager and of an equalizer of the proposed band.
  • the dynamic spectral channel bandwidth manager works analogously to others existing on other equipment. telecommunications: it creates mechanisms for living with other adjacent own systems - frequently speaking - so that they can function at the same time without creating interference between them. This dynamic management system will allow to take advantage of the entire capacity of the channel (high and medium voltage power lines) in the face of dynamic changes in its information transmission capacity
  • the system (1) of the invention comprises the configuration of nodes (2) of access to the network (3) of medium or high voltage to establish data communication by carrier wave at high speed, obtaining speed ratios much higher than 64 kbits / s
  • Each of the nodes (2) is constituted by an input / output interface (4) that supports IP protocols, and associated with a broadband MODEM (5) with OFDM modulation or similar.
  • the node incorporates a signal and impedance adapter (6) that performs the signal amplification in the entire band (40-500 kHz) and not only in one or more of the 4 kHz channels as the existing equipment, completing the node with the elements (7) of physical connection to the network (3).
  • the MODEMs of the origin and destination nodes could be replaced respectively by a modulator and a demodulator.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

Method and system for broadband digital transmission via high and medium voltage networks; of the type of method comprising data transmission by means of digital modulation in the frequency band between 40 and 500 kHz; which comprises transmission of the information in IP packets using broadband digital modulation with multiple carriers; an increase in transmit power; and spectral dynamic management of interference with already installed digital or analogue carrier systems and adjacent associated nodes, as well as equalization of the entire band.

Description

PROCEDIMIENTO Y SISTEMA DE TRANSMISIÓN DIGITAL DE BANDA ANCHA A TRAVÉS DE LAS REDES DE ALTA Y MEDIA TENSIÓN DIGITAL BROADBAND DIGITAL TRANSMISSION PROCEDURE AND SYSTEM THROUGH HIGH AND MEDIUM VOLTAGE NETWORKS

OBJETO DE LA INVENCIÓNOBJECT OF THE INVENTION

La presente invención se refiere a un procedimiento y sistema de transmisión digital en banda ancha utilizando como canal de transmisión las redes de alta y media tensión y aplicando técnicas modernas de modulación de banda ancha que consiguen tasas de velocidad mucho mayores que los equipos actuales.The present invention relates to a method and digital broadband transmission system using high and medium voltage networks as a transmission channel and applying modern broadband modulation techniques that achieve much higher speed rates than current equipment.

ANTECEDENTES DE LA INVENCIÓNBACKGROUND OF THE INVENTION

Las compañías eléctricas y operadores nacionales de transporte de electricidad utilizan los sistemas de Onda Portadora en las redes eléctricas de Alta Tensión desde hace varias décadas. La banda asignada específicamente para Ia comunicación sobre líneas de alta tensión está comprendida entre los 40 y los 500 kHz y está dividida en canales de 4 kHz. Las modulaciones utilizadas deben funcionar en canales muy afectados por el ruido y ser eficaces espectralmente para mantener Ia canalización de 4 kHz. Por este motivo se utiliza un esquema de modulación en BLU (Banda Lateral Única) que es una modulación "muy sencilla" -en cuanto a capacidad de transmisión de información-. Se utiliza, por ejemplo, para modular un canal telefónico básico (3.400 Hz) sobre el que se trasmite voz y/o datos mediante un MODEM analógico estándar para banda telefónica.Electric companies and national electricity transport operators have used the Carrier Wave systems in High Voltage power networks for several decades. The band allocated specifically for communication on high voltage lines is between 40 and 500 kHz and is divided into 4 kHz channels. The modulations used must work in channels that are very affected by noise and be spectrally effective in maintaining the 4 kHz channel. For this reason, a BLU (Single Side Band) modulation scheme is used, which is a "very simple" modulation - in terms of information transmission capacity. It is used, for example, to modulate a basic telephone channel (3,400 Hz) on which voice and / or data is transmitted using a standard analog modem for telephone band.

Tradicionalmente las compañías eléctricas utilizan estos sistemas de onda portadora para el control de subestaciones, telefonía de operación y para Ia comunicación de las protecciones de las líneas de alta tensión (teleprotecciones), donde se intercambia poca información y Ia velocidad es de unos pocos kbits/s -con modulación de banda estrecha- que ya resulta suficiente. La evolución natural de los equipos se ha centrado en Ia utilización de modulaciones digitales que se aplican a varios canales de 4 kHz, obteniendo velocidades de transmisión de 64 kbits/s. Sin embargo Ia velocidad de transmisión de 64 kbits/s sigue resultando escasa en comparación con otras tecnologías, como Ia fibra óptica, y resulta poco adecuado para los nuevos entornos de control y supervisión, Io que supone otro inconveniente.Traditionally, electricity companies use these carrier wave systems for substation control, operation telephony and for the communication of high voltage line protections (teleprotections), where little information is exchanged and the speed is a few kbits / s -with narrowband modulation- That is enough. The natural evolution of the equipment has focused on the use of digital modulations that are applied to several 4 kHz channels, obtaining transmission speeds of 64 kbits / s. However, the transmission speed of 64 kbits / s is still poor compared to other technologies, such as fiber optics, and is not very suitable for new control and supervision environments, which is another inconvenience.

Estos inconvenientes se subsanan con Ia utilización del procedimiento y sistema de Ia invención.These drawbacks are remedied with the use of the method and system of the invention.

DESCRIPCIÓN DE LA INVENCIÓNDESCRIPTION OF THE INVENTION

El procedimiento de Ia invención sirve de una manera óptima para conseguir comunicaciones sobre líneas eléctricas de alta y media tensión con tasas de velocidad ampliamente superiores a los 64 kbits/s medianteThe process of the invention serves in an optimal way to achieve communications on high and medium voltage power lines with speed rates widely exceeding 64 kbits / s by

Ia utilización de toda o casi toda Ia banda disponible mediante Ia transmisión de datos en paquetes IP.The use of all or almost all the band available through the transmission of data in IP packets.

Para ello Ia invención utilizará Ia misma banda de frecuencias para Ia transmisión de datos que Ia utilizada hasta ahora -comprendida entre los 40 y 500 kHz-.For this, the invention will use the same frequency band for the data transmission as the one used so far - understood between 40 and 500 kHz.

Para conseguir velocidades de transmisión de datos alta (» 64 kbits/s), en las líneas eléctricas de alta y media tensión se requiere densidades espectrales de 9-10 bits/Hz, y relaciones señal a ruido de como mínimo 20-30 decibelios, por Io que Ia invención propone Ia utilización de una modulación de banda ancha, típicamente una modulación OFDM de centenares de portadoras moduladas en QAM (modulación de amplitud en cuadratura), requiriendo elevadas potencias de transmisión. Al utilizarse toda o casi toda Ia banda se requerirá una potencia de emisión distribuida en toda Ia banda y será bastante superior a Ia utilizada hasta ahora (en términos absolutos). En los equipos actuales Ia potencia de emisión queda restringida a los canales de 4 kHz asignados.To achieve high data transmission rates (»64 kbits / s), high and medium voltage power lines require spectral densities of 9-10 bits / Hz, and signal to noise ratios of at least 20-30 decibels, Therefore, the invention proposes the use of a broadband modulation, typically an OFDM modulation of hundreds of carriers modulated in QAM (quadrature amplitude modulation), requiring high transmission powers. When using all or almost the entire band, an emission power distributed throughout the band will be required and will be much higher than the one used so far (in absolute terms). In current equipment, the emission power is restricted to the assigned 4 kHz channels.

Es posible que puedan producirse interferencias con los sistemas de portadora analógicos y digitales ya instalados, por Io que Ia invención propone Ia implementación lógica de un gestor de estas interferencias así como de un ecualizador de Ia banda de frecuencias propuesta.It is possible that interference with the analog and digital carrier systems already installed may occur, so that the invention proposes the logical implementation of a manager of these interferences as well as an equalizer of the proposed frequency band.

Para materializar el procedimiento de Ia invención, el sistema de Ia invención propone implementar en Ia red que se trate una serie de nodos de intercambio de datos en banda ancha, estando cada uno de los mismos constituidos por una interfaz de protocolos IP, un MODEM de banda ancha que trabaje en Ia banda de frecuencias prevista (40 - 500 kHz), así como un adaptador de señal tanto en amplitud como en impedancia en toda Ia banda de frecuencias de 40 - 500 kHz.To materialize the method of the invention, the system of the invention proposes to implement in the network that a series of nodes of broadband data exchange is treated, each of them being constituted by an IP protocol interface, a MODEM of broadband that works in the expected frequency band (40 - 500 kHz), as well as a signal adapter in both amplitude and impedance in the entire frequency band of 40 - 500 kHz.

BREVE DESCRIPCIÓN DE LOS DIBUJOSBRIEF DESCRIPTION OF THE DRAWINGS

La figura 1 muestra un esquema del sistema de Ia invención donde se representan dos nodos que se comunican entre sí.Figure 1 shows a scheme of the system of the invention where two nodes that communicate with each other are represented.

DESCRIPCIÓN DE UNA REALIZACIÓN PRACTICA DE LA INVENCIÓNDESCRIPTION OF A PRACTICAL EMBODIMENT OF THE INVENTION

El procedimiento de Ia invención sirve para Ia transmisión de datos por Ia red de alta y media tensión en banda ancha en cooperación con Ia utilización de modulaciones del tipo OFDM o similar. Comprende Ia transmisión de Ia información en paquetes IP con utilización de Ia banda de frecuencias comprendida entre 40 y 500 khz en cooperación con una modulación de banda ancha y aumento de Ia potencia de emisión, y con Ia implementación lógica de un gestor dinámico de interferencias y de un ecualizador de Ia banda propuesta. El gestor dinámico espectral del ancho de banda del canal funciona de modo análogo a otros existentes en otros equipos de telecomunicaciones: crea mecanismos para Ia convivencia con otros sistemas propios adyacentes -frecuencialmente hablando-, de manera que puedan funcionar al mismo tiempo sin crearse interferencias entre ellos. Este sistema de gestión dinámica permitirá aprovechar toda Ia capacidad del canal (líneas eléctricas de alta y media tensión) ante cambios dinámicos en su capacidad de transmisión de informaciónThe method of the invention serves to transmit data over the high and medium voltage network in broadband in cooperation with the use of modulations of the OFDM type or the like. It comprises the transmission of the information in IP packets with the use of the frequency band between 40 and 500 kHz in cooperation with a broadband modulation and increase in the emission power, and with the logical implementation of a dynamic interference manager and of an equalizer of the proposed band. The dynamic spectral channel bandwidth manager works analogously to others existing on other equipment. telecommunications: it creates mechanisms for living with other adjacent own systems - frequently speaking - so that they can function at the same time without creating interference between them. This dynamic management system will allow to take advantage of the entire capacity of the channel (high and medium voltage power lines) in the face of dynamic changes in its information transmission capacity

El sistema (1 ) de Ia invención comprende Ia configuración de unos nodos (2) de acceso a Ia red (3) de media o alta tensión para establecer comunicación de datos por onda portadora a alta velocidad, consiguiendo ratios de velocidad muy superiores a 64 kbits/s.The system (1) of the invention comprises the configuration of nodes (2) of access to the network (3) of medium or high voltage to establish data communication by carrier wave at high speed, obtaining speed ratios much higher than 64 kbits / s

Cada uno de los nodos (2) está constituido por una interfaz (4) de entrada/salida que soporta protocolos IP, y asociada a un MODEM (5) de banda ancha con modulación OFDM o similar.Each of the nodes (2) is constituted by an input / output interface (4) that supports IP protocols, and associated with a broadband MODEM (5) with OFDM modulation or similar.

A Ia salida del MODEM (5) el nodo incorpora un adaptador (6) de señal e impedancias que realiza Ia amplificación de señal en toda Ia banda (40-500 kHz) y no sólo en uno o varios de los canales de 4 kHz como los equipos existentes actualmente, completándose el nodo con los elementos (7) de conexión física a Ia red (3).At the output of the MODEM (5) the node incorporates a signal and impedance adapter (6) that performs the signal amplification in the entire band (40-500 kHz) and not only in one or more of the 4 kHz channels as the existing equipment, completing the node with the elements (7) of physical connection to the network (3).

En caso de que Ia comunicación entre nodos fuera monodireccional, los MODEMs de los nodos de origen y destino podrían sustituirse respectivamente por un modulador y un demodulador.If the communication between nodes was monodirectional, the MODEMs of the origin and destination nodes could be replaced respectively by a modulator and a demodulator.

Descrita suficientemente Ia naturaleza de Ia invención, así como Ia manera de realizarse en Ia práctica, debe hacerse constar que las disposiciones anteriormente indicadas y representadas en los dibujos adjuntos son susceptibles de modificaciones de detalle en cuanto no alteren el principio fundamental. Described sufficiently the nature of the invention, as well as the way of carrying out it in practice, it should be noted that the provisions indicated above and represented in the attached drawings are subject to modifications in detail as long as they do not alter the fundamental principle.

Claims

REIVINDICACIONES 1.-Procedimiento y sistema de transmisión digital de banda ancha en redes de alta y media tensión; del tipo de procedimiento que comprenden Ia transmisión de los datos mediante modulación digital en Ia banda de frecuencias comprendida entre 40 y 500 kHz; caracterizado dicho procedimiento porque comprende Ia transmisión de Ia información en paquetes IP con utilización de modulación digital de banda ancha con múltiples portadoras; el aumento de Ia potencia de emisión; y Ia gestión dinámica espectral de interferencias con sistemas de portadora digitales, analógicos ya instalados y nodos propios adyacentes, así como Ia ecualización de toda Ia banda.1.-Procedure and digital broadband transmission system in high and medium voltage networks; the type of procedure comprising the transmission of the data by digital modulation in the frequency band between 40 and 500 kHz; said procedure characterized in that it comprises the transmission of the information in IP packets with the use of digital broadband modulation with multiple carriers; the increase of the emission power; and the dynamic spectral management of interferences with already installed digital, analog carrier systems and adjacent own nodes, as well as the equalization of the entire band. 2. -Sistema según reivindicación 1 caracterizado porque cada nodo de acceso a Ia red está constituido por una interfaz de protocolos IP, un MODEM de banda ancha que trabaja en Ia banda de frecuencias comprendida entre los 40 y 500 kHz y un adaptador de señal en amplitud y de impedancia en toda Ia banda de frecuencias en orden a conseguir ratios de transmisión muy superiores a 64 kbits/s. 2. -System according to claim 1 characterized in that each network access node is constituted by an IP protocol interface, a broadband MODEM that works in the frequency band between 40 and 500 kHz and a signal adapter in amplitude and impedance throughout the frequency band in order to achieve transmission rates much higher than 64 kbits / s. 3.- Sistema según reivindicaciones 1 y 2 caracterizado porque incluye Ia implementación lógica de un gestor dinámico del tráfico, adaptando el sistema -en todo momento- el tráfico de datos con Ia capacidad física del canal. Este sistema incorpora mecanismos de control de tráfico que tiene en cuenta el tráfico entrante, Ia velocidad en tiempo real y Ia tasa de errores del canal.3. System according to claims 1 and 2 characterized in that it includes the logical implementation of a dynamic traffic manager, adapting the system - at all times - data traffic with the physical capacity of the channel. This system incorporates traffic control mechanisms that take into account incoming traffic, real-time speed and channel error rate. 4.-Procedimiento según reivindicación 1 caracterizado porque Ia modulación en banda ancha consiste en una modulación en multiplexado de partes de frecuencias ortogonales OFDM de centenares de portadoras. 4. Method according to claim 1 characterized in that the broadband modulation consists of a multiplexed modulation of parts of orthogonal frequencies OFDM of hundreds of carriers.
PCT/ES2007/070106 2006-06-28 2007-05-30 Method and system for broadband digital transmission via high and medium voltage networks Ceased WO2008000880A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ESP200601743 2006-06-28
ES200601743A ES2326009B1 (en) 2006-06-28 2006-06-28 PROCEDURE AND SYSTEM OF DIGITAL BROADBAND TRANSMISSION THROUGH HIGH AND MEDIUM VOLTAGE NETWORKS.

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WO2008000880A1 true WO2008000880A1 (en) 2008-01-03

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1011235A2 (en) * 1998-12-15 2000-06-21 Nortel Networks Corporation Reception of multicarrier signals over power lines
EP1014640A2 (en) * 1998-12-22 2000-06-28 Nortel Networks Corporation Multicarrier transmission on power lines
US20060049693A1 (en) * 2004-09-08 2006-03-09 Satius, Inc. Apparatus and method for transmitting digital data over various communication media

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1011235A2 (en) * 1998-12-15 2000-06-21 Nortel Networks Corporation Reception of multicarrier signals over power lines
EP1014640A2 (en) * 1998-12-22 2000-06-28 Nortel Networks Corporation Multicarrier transmission on power lines
US20060049693A1 (en) * 2004-09-08 2006-03-09 Satius, Inc. Apparatus and method for transmitting digital data over various communication media

Also Published As

Publication number Publication date
ES2326009B1 (en) 2010-06-25
ES2326009A1 (en) 2009-09-28

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