DLC-VIT4IP: Distribution Line Carrier - Verification, Integration and Test of PLC Technologies and IP Communication for Utilities

Power Generation, Transport and Distribution

The main advantage of the DLC communication technology is that it uses the existing infrastructure, in this case the medium voltage and low voltage distribution network. The physical medium for DLC communication is the electrical wiring and cables of the electrical distribution network, yet this network was originally designed to distribute electricity to the end user and not to provide communication. Its physical and network characteristics are mainly chosen to transport power efficiently at a certain line voltage and frequency. To understand some of the challenges of the distribution line carrier communication it is necessary to describe the distribution network.

In the past, electricity was provided by many small power plants and local distribution networks owned by hundreds of different utilities. By interconnecting these small networks, larger networks emerged resulting in a more efficient and reliable power provisioning. The decentralised electricity model with local generators evolved into a centralized model with larger generators. Along with the larger generators came the high voltage transmission network, the medium and low voltage distribution network to transport the electricity to the customer.

Before the electricity is consumed by the end-user it has passed several stages. Power plants convert primary energy (coal, oil, natural/bio gas, nuclear) and renewable energy (wind, sun, hydro..) into electric energy. The generated electricity goes through various transformations; e.g. stepping up the voltage in order to transmit over large distances and various levels of stepping down the voltage to its final end-user (domestic, commercial, or industrial use). After generation in power stations, electrical energy needs to be transported to the areas where it is consumed. This transport is more efficient at higher voltage, which is why power generated at 10 - 30 kV is converted by transformers into typical voltages of 220 kV up to 400 kV, or even higher. Since the majority of electrical installations operate at lower voltages, the high voltage needs to be converted back close to the point of use. The main reason to step down voltage is to increase the safety for the end user and reduce costs of insulation material. The first step down is transformation to 33 - 150 kV. It is often the level at which power is supplied to major industrial customers. Distribution companies then transform power further down to the consumer mains voltage.

In this way, electrical energy passes through an average of four transformation stages before being consumed. A large number of transformers of different classes and sizes is needed in the transmission and distribution network, with a wide range of operating voltages. Large transformers for high voltages are called power transformers. The last transformation step into the consumer mains voltage (in Europe 400/230 V) is done by the distribution transformer.

The distribution grid distributes the electric energy to the customers and consists of the medium and low voltage network. The Medium Voltage (MV) Network distributes the electric energy to the secondary distribution substations. The European medium voltage (MV) is usually between 1 and 60 kV. The Low Voltage (LV) Network distributes the electric energy from the secondary distribution substations to the low voltage customers. The voltage (LV) is below 1 kV.

The configuration of the power distribution network depends on the deployment of electrical load of consumer, geography of the service area, concepts concerning the power-system operation, and those concerning protection in the event of a system fault.
The power distribution network is designed for the efficient transfer of power at 50 or 60 Hertz. While this type of system works well for the distribution of power at power line frequencies, it presents certain challenges when used as a communication system.

Topology

The topology of the high voltage network is commonly a closed ring topology with a few cases of open ring topology. The medium voltage network is laid out mainly as an open ring topology, with a few cases of star topology for both urban and rural areas. The low voltage network is an open ring topology for urban areas and star topology for rural areas.

DLC-VIT4IP: Distribution Line Carrier - Verification, Integration and Test of PLC Technologies and IP Communication for Utilities

Home Partners Workpackages Technical Interest Group Member Login Downloads Project Overview The Power Network DLC Infrastructure DLC Equipment DLC-VIT4IP Protocol Stack wsplc2011 Search: The research leading to this results has recieved funding from the European Communitiy's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 247750.	Power Generation, Transport and Distribution The main advantage of the DLC communication technology is that it uses the existing infrastructure, in this case the medium voltage and low voltage distribution network. The physical medium for DLC communication is the electrical wiring and cables of the electrical distribution network, yet this network was originally designed to distribute electricity to the end user and not to provide communication. Its physical and network characteristics are mainly chosen to transport power efficiently at a certain line voltage and frequency. To understand some of the challenges of the distribution line carrier communication it is necessary to describe the distribution network. In the past, electricity was provided by many small power plants and local distribution networks owned by hundreds of different utilities. By interconnecting these small networks, larger networks emerged resulting in a more efficient and reliable power provisioning. The decentralised electricity model with local generators evolved into a centralized model with larger generators. Along with the larger generators came the high voltage transmission network, the medium and low voltage distribution network to transport the electricity to the customer. Before the electricity is consumed by the end-user it has passed several stages. Power plants convert primary energy (coal, oil, natural/bio gas, nuclear) and renewable energy (wind, sun, hydro..) into electric energy. The generated electricity goes through various transformations; e.g. stepping up the voltage in order to transmit over large distances and various levels of stepping down the voltage to its final end-user (domestic, commercial, or industrial use). After generation in power stations, electrical energy needs to be transported to the areas where it is consumed. This transport is more efficient at higher voltage, which is why power generated at 10 - 30 kV is converted by transformers into typical voltages of 220 kV up to 400 kV, or even higher. Since the majority of electrical installations operate at lower voltages, the high voltage needs to be converted back close to the point of use. The main reason to step down voltage is to increase the safety for the end user and reduce costs of insulation material. The first step down is transformation to 33 - 150 kV. It is often the level at which power is supplied to major industrial customers. Distribution companies then transform power further down to the consumer mains voltage. In this way, electrical energy passes through an average of four transformation stages before being consumed. A large number of transformers of different classes and sizes is needed in the transmission and distribution network, with a wide range of operating voltages. Large transformers for high voltages are called power transformers. The last transformation step into the consumer mains voltage (in Europe 400/230 V) is done by the distribution transformer. The distribution grid distributes the electric energy to the customers and consists of the medium and low voltage network. The Medium Voltage (MV) Network distributes the electric energy to the secondary distribution substations. The European medium voltage (MV) is usually between 1 and 60 kV. The Low Voltage (LV) Network distributes the electric energy from the secondary distribution substations to the low voltage customers. The voltage (LV) is below 1 kV. The configuration of the power distribution network depends on the deployment of electrical load of consumer, geography of the service area, concepts concerning the power-system operation, and those concerning protection in the event of a system fault. The power distribution network is designed for the efficient transfer of power at 50 or 60 Hertz. While this type of system works well for the distribution of power at power line frequencies, it presents certain challenges when used as a communication system. Topology The topology of the high voltage network is commonly a closed ring topology with a few cases of open ring topology. The medium voltage network is laid out mainly as an open ring topology, with a few cases of star topology for both urban and rural areas. The low voltage network is an open ring topology for urban areas and star topology for rural areas.