D-Axis Disturbance Injection and Wavelet Transform based Islanding Detection

The unplanned islanding formation is needed to be detected and subsequently the distributed generators (DG) required to be de-energized. This becomes essential to safeguard the maintenance personnel and the electrical equipment. In this work, a hybrid islanding detection strategy is proposed based on d-axis current disturbance injection and subsequent analysis of the voltage by the wavelet transform. The proposed strategy is efficient to detect the islanding event, and also classify the non-islanding events precisely even though the measured voltage or frequency magnitudes are out of its operating zone. Thus the proposed strategy allows the DGs for the ride through capability. The proposed strategy is corroborated using MATLAB/Simulink 2024a