With the increased growth rate of the population their demand for electrical power usage in terms of basic necessities to keep their successful lifestyle also increases. To fulfill this requirement distributed generation (DG) play a vital role in the generation of electrical power. The distribution network which usually consist of the medium as well as low voltage networks on the basis of research analysis which mainly focuses on medium voltage network. The main fundamental objectives in this research work are to support the increased load growth, enhancement of reliable power operation, the better quality of power, network prevention from contingencies and line losses in the power system. One of the main issues in this research work is islanding detection, a situation in which a portion of the network is detached from the central main network yet to be energized by the distributed generation. To detect such situation under different load conditions a case study is done in which different techniques are commonly used that uses different relays which are under and over for voltage, current, frequency, vector surge and rate of change frequency (ROCOF). To analyze the performance of these techniques for the non-detective zone (NDZ) and time of operation MATLAB / Simulink software's are used to perform the simulation.