Hantering av småskalig elproduktion
Utveckling av modell för dokumentation och elkvalitetsberäkningar
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected. Criteria for what constitutes good power quality are defined in national and international prescribed standards, and accountability for these to be sustained are upon the distribution system operators. A number of these companies use the software dpPower developed by Digpro AB to perform network calculations on their grids to ensure that the power quality meets established requirements. The program does not include any customized tools to manage distributed generation, which this project aims to develop.The tools developed in the program are able to handle distributed generation considering documentation and calculations. The calculations take into account whether the plants consists of solar cells or wind turbines, how they are connected to the grid, as well as their rated power. The parameters calculated by the new methods are slow voltage fluctuations, rapid voltage changes, voltage unbalance and flicker.