Distributed generation and its influence on voltage changes in low voltage grids and transformer loading

The installed power in distributed generation sources is growing and we record recently more of domestic consumers equipped with the small sources, that operates in low voltage grids. The conception of power supply process is changing from the central production to the decentralization of electricity production. Despite the advantages of distributed generation, the utilities in energy sector have to face also the technical problems that are coming with it. The power system was build to produce the energy in central power plants, to transfer and to distribute it thru long distances to the consumption places in low or medium voltage grids. Radial connection of 22kV power grids, transformers without the remote control of tape changes, harmonics, etc. are the technical barriers for distributed generation. Each source has to meet the technical condition for connection of source to the grid, that are usually set by the relevant distribution system operator. One of the most important condition is the requirement for steady state voltage change. This paper is focused on the analysis of the distribution generation according to the voltage changes in steady state operation and the transformer loading.