Analysis of Distributed Energy Resources Impact on Islanding Detection Techniques

During an islanding event, the distributed resources may keep the system loads operating without frequency and voltage reference from the main grid. Hence, system stability and some equipment operation can be compromised. Therefore, there are many studies proposing islanding detection techniques that allow fast switching of the distributed resources control mode or its disconnection from the grid. Considering this, the present paper aimed to evaluate the impact of distributed energy resources on three islanding detection techniques: one based on under/overfrequency; another based on the Rate of Change of Frequency (ROCOF); and the last one based on the Rate of Change of Power (ROCOP). Thus, it was firstly simulated fault and islanding events on a modelled microgrid. The technique's accuracy was compared by connecting only a synchronous generator in one scenario and connecting a battery energy storage system and a synchronous generator in another one. Additionally, in the second scenario, the energy storage system output power was changed and it was considered the injection and the absorption of power. Finally, it could be concluded that the energy storage system connection caused some variation on the islanding detection techniques, specially in the one based on under/overfrequency.