Transient based protection scheme for distribution grids supplied with distributed generation

The integration of distributed generation transforms current distribution networks from vertically operated to horizontally operated. This transition leads to problems related to protection coordination. In the future, new protection philosophies should be applied which guarantee the increase of the during-fault distributed generation availability. The paper presents a cost-effective protection scheme based on fault transient analysis. Numerous cases are simulated indicating that the protection principle works reliably independent from the distributed generation presence. Simulations are carried out using ATP/EMTP software package and the generated data are processed by applying Wavelet transform within Matlab environment.