PERFORMANCE EVALUATION OF LOSS OF GRID AND ITS PROTECTION

Abstract

This thesis presents a passive based method islanding detection for distribution generation network connected to a utility grid. The passive technique is based on change of voltage phase angle at the point of common coupling (PCC), and a new variable ‘Delta’ is introduced which helps to increase the efficiency of the proposed method. Various islanding and non-islanding events are simulated on MATLAB/ Simulink environment on the equivalent 3 bus system and IEEE 34 multi-bus system and the proposed method is tested on it. The results are the proof that the proposed method is clearly able to distinguish between the islanding and non-islanding events. Further, the proposed technique is capable of removing the problem of Non Detection Zone (NDZ) completely, works perfectly for multiple DG case and nuisance tripping can be avoided during various non-islanding events. Moreover, high speed of detection and immunity from the capacity of the distribution network are key features of the proposed method.