Matlab/Simulink implementation & simulation of islanding detection using passive methods

The extensive use of Distributed Generators in Electrical and power systems made it a must to explore its functionality and the issues related to their connection to the grid. One of the main issues is unintentional islanding, which has been considered and studied for many years since it has serious consequences on electric systems and line workers safety. Therefore, islanding detection methods is a motivating topic to be discussed by many scientists and engineers. Islanding detection methods can be divided into two main categories, remote methods and local methods; the later method is classified into passive techniques and active techniques. This paper represents two methods of the passive islanding techniques and a simple comparison between both of them. The selected two methods are the over/under voltage and over/under frequency detection method and the wavelet based method. These two were implemented and simulated using Matlab/Simulink toolboxes. The simulation results proved that the two studied methods have a good performance for parallel RLC loads having quality factor of 2.5. The simulated passive techniques have no negative impact on the power quality.