Efiect of Renewable Energy Sources to the Stability of the Low Voltage Distribution Networks

The paper describes the recent development in the area of renewable energy sources (RES). Shows the situations in countries supporting a great growth of RES, particularly in photovoltaic energy what leads to the big problems. The modelling of situation shows that in a very near future there will be a big over∞ow of electrical energy production in the low voltage networks (LVN). It would evoke necessity to transfer energy into higher voltage networks. However it's not possible, because of the protection systems of high voltage networks (HVN) are developed for the opposite ∞ow of energy. The traditional power engineering industry assumes centralized energy sources (power plants), and delivers electrical energy into consumers via very high voltage networks (transition networks VHN), high voltage networks (HVN) into LVN. In the low voltage networks the energy is totally consumed. Because of the existing protection systems in the HVN, and the recent energy distributors and producers correspond with this traditional conception, is necessary to consume all energy from RES in the low voltage networks where it was produced. Our contribution deals with this phenomenon and ofiers some part solution of the problem.