medium voltage data communications network for SCADA transmissions between the transformer stations

The technology

The increased need for energy, along with the most recent trends in telecommunications, allowed for different approaches of the energy grid. Nowadays, the standard concept of a unidirectional distribution network, with the sole purpose to transport the electricity from central transformer points to consumers, is replaced by a complex bidirectional communication system over the medium voltage lines. Due to harsh noise and variations in equipment and standards, communications over the power grid is still challenging. In most countries, the medium voltage power distribution network reaches far and wide into almost every inhabited area, this characteristic making the grid suitable for communication. However, current medium voltage distribution grids were not initially created for communication purposes, therefore this raises a series of issues.

 

The location

The city of Ploieşti, one of the largest cities in Romania, is situated in the center of the country and it is home to more than 200,000 people, making it the 9th most populous city in Romania.

The town originated in the last decade of the 16th century, becoming a center for trade and handicraft manufacturing in the 17th and 18th centuries. In the mid-19th century the Ploieşti region was one of the world’s leading oil extraction and refinery sites. The world’s first large refinery opened at Ploieşti in 1856-1857, with US investment.

 

The challenge

FDEE Electrica Distribuţie Muntenia Nord S.A. is nowadays developing a complex process of modernization of the electricity distribution network in Ploieşti; the company needed a better control and detailed overview of the electric grid in the entire city in order to provide their services more efficiently. FDEE Electrica Distribuţie Muntenia Nord S.A.’s objective was to identify a more suitable method for data collecting from the grid. They aimed to interconnect the transformer stations and to manage the entire network through SCADA transmission.
In order to achieve the proposed goal, FDEE Electrica Distribuţie Muntenia Nord S.A., together with Eximprod Grup, the entrepreneur of the modernization works, partnered with Flashnet for the medium voltage broadband power line data communication project in Ploieşti. Flashnet was the leading choice as the company develops and integrates solutions that optimize the energy distribution network and offer new ways to both monitor and manage the electric grid. Headquartered in Braşov, Flashnet has an advanced know-how in the development and implementation of power line data communication technology. Flashnet’s portfolio includes Smart Grid Braşov project, one of the first Smart Grid installations in Europe, and inteliLIGHT, a street lighting remote management system, already installed in several cities around the world.

 

The solution

The technology used in the Ploieşti project consists of a medium voltage data communications network for SCADA transmissions between the transformer stations. The communication devices are monitored by the OpenGrid; a standalone software interface specially designed to control and manage the data collected from the grid. The project consists of 64 Ormazabal API-2000-SA MV BPL devices installed in 64 corresponding transform stations.

 

Cell consisting of nine transformer stations

 

The project took place between July-August 2013 and the transform stations were grouped in 8 “cells”, consisting of various numbers of Transformer Stations, according to geographic, available communication network and positioning criteria. Power line communication between the transformer stations is carried out through the Ormazabal API-2000-SA MV BPL devices. They are connected with the medium voltage lines via conductive or inductive couplers, used in concordance with the existing conditions at every transformer station. Thus, for longer distances between the transformer station conductive couplers were used, in other cases inductive couplers being preferred.

 

Medium voltage communication devices installed at the transform station

 

The medium voltage equipment installed in every transform station enables data transmission between the stations of the same cell. Each cell has a predefined “node” for power line communication between the transform stations part of the same cell, but also for data transmission via GPRS with the central server at FDEE Electrica Distribuţie Muntenia Nord S.A.’s headquarters.

Software monitoring of the medium voltage lines communication is monitored in OpenGrid, a graphical interface designed to provide real-time information on parameters defining the operational grid.

 

Daily signal level

 

Project includes:
ORMAZABAL API-2000-SA MV BPL devices
EICHOF inductive couplers
ARTECHE plug cap couplers
ARTECHE conductive couplers
OPENGRID management software

 

Results and conclusions

Traditional utilities systems use SCADA low-speed data transmission with less-than-desired stability, therefore the results obtained this way did not respond to current requirements in a properly manner. At the moment, FDEE Electrica Distribuţie Muntenia Nord S.A. is in a process of modernization of the distribution grid, so that the Flashnet challenge was particularly interesting: a solution that is equally compatible with already enhanced transform stations and those still in the process of being modernized. Thus, the conditions for achieving a stable and functional communication over the medium voltage lines vary with local network topography.

Through Flashnet, FDEE Electrica Distribuţie Muntenia Nord S.A. is now the beneficiary of an innovative medium voltage broadband power line data communication system installed on their grid, with very fast speeds of Mbps. FDEE Electrica Distribuţie Muntenia Nord S.A.’s intentions are to continue the medium voltage broadband power line data communication implementation in the remaining parts of the city of Ploieşti, as the results exceeded the most optimistic expectations.

 

SNR graphic

 

The Ploieşti project demonstrated that smart grids are no longer just a vision of the future, but a proven fact. The devices installed here on the existing grid and the whole solutions are fully functional, providing essential information for improving and streamlining the management of the grid.
Thus, based on the excellent results of this project, FDEE Electrica Distribuţie Muntenia Nord S.A. intends to continue its partnership with Flashnet to extend the medium voltage lines communication rollout in the whole city of Ploieşti. Following the installation of the medium voltage lines communication devices, the companies involved in the project settled the premises for a complex architecture required in future Smart Grids.