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The effects of international standards on the design of a micro grid in a rural area

Sandung, Magdalena LU (2017) In CODEN:LUTEDX/TEIE EIE920 20171
Industrial Electrical Engineering and Automation
Abstract
The energy sector in the world today is in the middle of a huge challenge regarding grid development and power production. Whilst a significant part of the world's population are struggling without access to electricity, the more developed part of the world is trying to replace existing energy sources into renewable ones, and are also facing the challenge of an aging grid which is in desperate need of reconstruction. The technology and knowledge is not found everywhere and to be able to help other countries in their way towards functioning grids and renewable energy sources, well developed standards are very important for maintaining quality but also for inter-connection of grids in the world.

This thesis investigates the differences... (More)
The energy sector in the world today is in the middle of a huge challenge regarding grid development and power production. Whilst a significant part of the world's population are struggling without access to electricity, the more developed part of the world is trying to replace existing energy sources into renewable ones, and are also facing the challenge of an aging grid which is in desperate need of reconstruction. The technology and knowledge is not found everywhere and to be able to help other countries in their way towards functioning grids and renewable energy sources, well developed standards are very important for maintaining quality but also for inter-connection of grids in the world.

This thesis investigates the differences between existing standards in Sweden and Venezuela, by applying them on the design of a fictitious grid and comparing the technological and economical outcome of it. The grids are designed for a village in Venezuela, but with two different load profiles and with the two different countries' standards. The focus is put on standards regarding voltages, frequency, cable structure and short circuit currents, which are the standards with the most relevance in a simulation study. The simulation model is built in PowerFactory, a grid calculation program, and four different grids have been built in order to cover all scenarios. The simulations in the program shows voltage deviation, electrical loading, losses and short circuit currents, and are all part of the purpose to design a functioning grid. An economical analysis has been made for each grid, with cost calculations developed at ÅF and from sources in Venezuela.

The investigation about the standards in the two countries immediately points out the lack of standards in Venezuela. The country's grid development seems to be mostly based on experience and guidelines, which has caused several problems when trying to the design the grids. Swedish standards are plenty and all collected in books and documents, and they cover all basic grid structures and methods. The standards in Venezuela can all be found in one document, which covers a few basics, but is more focused on specific event and scenarios. This complicates the development of the grid. There are also some standards that affect the whole system and causes problems, but that can not be changed easily, as the voltage. The simulations show that the decreased voltage (compared to the Swedish voltage level) leads to higher currents, which in turn causes higher losses and heavier electrical loading on the cables. Since the cables in Venezuela use copper conductors, the cost is already high, but with a heavy electrical loading, the cables will not last for long and the replacement of them will cause even higher costs. The increased current also caused a high voltage drop and in order to solve all these problems, and to keep the same standard and quality as the Swedish grids, the cables needed to be thicker in order to be dimensioned properly. Larger cables are more expensive, and since they already play a huge role in the total cost calculation, it is quite negative.

Looking at the economical differences in the grids, the Venezuelan grid only uses copper cables, which is known to be much more expensive than aluminium cables, used in the Swedish grids. Thereby, a large difference can bee seen in the cable costs, where the Venezuelan cables cost more than the entire Swedish grids, including digging, trucks, transformer stations and much more. Comparing the two load profiles, it shows that a larger grid does not significantly affect the total costs. The cost calculations shows that for a Swedish company, it could be an option to enter the electricity market of Venezuela. The question would be weather to adopt the Venezuelan standards, and work with the main grid, or not adopt the Venezuelan standards and see if there is a possibility to work only with islanded micro grids. It could be an option to work within their standards but with Swedish cable structure, and change the copper cables into aluminium cables, to reduce the costs.

The ease of using Swedish grid design, the functionality and the total costs of the grids, points out the fact that well developed standards are very important when expanding old grids or building new ones. If more countries put focus on the development of international standards, all compatible with each other, it will expand the market in such way that the design and construction of grids in developing countries will be much easier. It will open up the market for foreign companies, that can contribute with their knowledge and experience, in order to speed up the development and create access to electricity to more people in the world. It will also create an easier way to ensure inter-connectivity inside of and between countries. (Less)
Please use this url to cite or link to this publication:
author
Sandung, Magdalena LU
supervisor
organization
course
EIE920 20171
year
type
H3 - Professional qualifications (4 Years - )
subject
keywords
electrical standards, international standards, micro grid
publication/series
CODEN:LUTEDX/TEIE
report number
5391
language
English
id
8914255
date added to LUP
2017-06-13 15:48:19
date last changed
2017-06-21 14:07:00
@misc{8914255,
  abstract     = {{The energy sector in the world today is in the middle of a huge challenge regarding grid development and power production. Whilst a significant part of the world's population are struggling without access to electricity, the more developed part of the world is trying to replace existing energy sources into renewable ones, and are also facing the challenge of an aging grid which is in desperate need of reconstruction. The technology and knowledge is not found everywhere and to be able to help other countries in their way towards functioning grids and renewable energy sources, well developed standards are very important for maintaining quality but also for inter-connection of grids in the world.

This thesis investigates the differences between existing standards in Sweden and Venezuela, by applying them on the design of a fictitious grid and comparing the technological and economical outcome of it. The grids are designed for a village in Venezuela, but with two different load profiles and with the two different countries' standards. The focus is put on standards regarding voltages, frequency, cable structure and short circuit currents, which are the standards with the most relevance in a simulation study. The simulation model is built in PowerFactory, a grid calculation program, and four different grids have been built in order to cover all scenarios. The simulations in the program shows voltage deviation, electrical loading, losses and short circuit currents, and are all part of the purpose to design a functioning grid. An economical analysis has been made for each grid, with cost calculations developed at ÅF and from sources in Venezuela.

The investigation about the standards in the two countries immediately points out the lack of standards in Venezuela. The country's grid development seems to be mostly based on experience and guidelines, which has caused several problems when trying to the design the grids. Swedish standards are plenty and all collected in books and documents, and they cover all basic grid structures and methods. The standards in Venezuela can all be found in one document, which covers a few basics, but is more focused on specific event and scenarios. This complicates the development of the grid. There are also some standards that affect the whole system and causes problems, but that can not be changed easily, as the voltage. The simulations show that the decreased voltage (compared to the Swedish voltage level) leads to higher currents, which in turn causes higher losses and heavier electrical loading on the cables. Since the cables in Venezuela use copper conductors, the cost is already high, but with a heavy electrical loading, the cables will not last for long and the replacement of them will cause even higher costs. The increased current also caused a high voltage drop and in order to solve all these problems, and to keep the same standard and quality as the Swedish grids, the cables needed to be thicker in order to be dimensioned properly. Larger cables are more expensive, and since they already play a huge role in the total cost calculation, it is quite negative.

Looking at the economical differences in the grids, the Venezuelan grid only uses copper cables, which is known to be much more expensive than aluminium cables, used in the Swedish grids. Thereby, a large difference can bee seen in the cable costs, where the Venezuelan cables cost more than the entire Swedish grids, including digging, trucks, transformer stations and much more. Comparing the two load profiles, it shows that a larger grid does not significantly affect the total costs. The cost calculations shows that for a Swedish company, it could be an option to enter the electricity market of Venezuela. The question would be weather to adopt the Venezuelan standards, and work with the main grid, or not adopt the Venezuelan standards and see if there is a possibility to work only with islanded micro grids. It could be an option to work within their standards but with Swedish cable structure, and change the copper cables into aluminium cables, to reduce the costs.

The ease of using Swedish grid design, the functionality and the total costs of the grids, points out the fact that well developed standards are very important when expanding old grids or building new ones. If more countries put focus on the development of international standards, all compatible with each other, it will expand the market in such way that the design and construction of grids in developing countries will be much easier. It will open up the market for foreign companies, that can contribute with their knowledge and experience, in order to speed up the development and create access to electricity to more people in the world. It will also create an easier way to ensure inter-connectivity inside of and between countries.}},
  author       = {{Sandung, Magdalena}},
  language     = {{eng}},
  note         = {{Student Paper}},
  series       = {{CODEN:LUTEDX/TEIE}},
  title        = {{The effects of international standards on the design of a micro grid in a rural area}},
  year         = {{2017}},
}