Design and implementation of different types of grounding system

Abstract

There is no doubt that safety is major concern of technology and development, because a system that is badly secured may put the human life on stake, moreoverthe non-safe installations reflect also on the economic cost as well as the energy loss, where according to statistics about 75% of electricity losses are due to faults on distribution networks, so it is essential to provide suitable protection schemes and relay selection to ensure the fastest disconnection of faulty parts in order to minimize outage times and thus improving the continuity of power supply. As one could not cover all safety systems, our concern is focused only on grounding methods and their protection techniques; we have discussed the different grounding types with advantages, disadvantages and applications of each. The main types are being discussed in this report are: TT, TN-C and IT systems each one has a special design and characteristic that differs from the others. Also the protection devices have discussed briefly showing the most important ones with their applications. The simulation has been performed for the three grounding systems stated previously and the test of tripping of the differential and electromagnetic thermal relay in each type. Finally the three systems have been implemented and tested to show their behaviors under different conditions such a phase to ground fault (load is short circuited).