Constraints for the interconnection of distributed generation in radial distribution systems

After the recent introduction of the competitive electricity market in many countries, the number of small-size generators connected to the distribution systems is rapidly increasing. This paper analyses the impact of distributed generation (DG) on medium voltage (MV) distribution networks. In particular the modifications of voltage profiles, line currents and short circuit currents caused by the introduction of a synchronous generator in the net are considered. For this purpose a real network in radial configuration is used, assuming various generator positions along the feeder and different values of supplied power in maximum and minimum load conditions. In this work, results obtained by computer simulation are reported, highlighting the allowable generation limits regarding different constraints.