A Novel Hybrid Island Detection Method for Microgrid with Photovoltaic and Energy Storage

Taking the microgrid with photovoltaic and energy storage (ES) as the research object, a hybrid islanding detection method combining passive and active methods is proposed to address the issue of the correlation between active power mismatch and voltage deviation when ES is in different operating state after islanding occurs. Firstly, based on the operating state of ES in the action zone after islanding occurs, the voltage variation characteristic is analyzed, thus the passive island detection criterion is formulated. Secondly, based on the operating state of ES in the non-action zone after islanding occurs, according to the correlation between reactive power mismatch and frequency deviation, the reactive power perturbation value is adaptively and actively adjusted in different frequency bands to make the frequency exceed the threshold, thus achieving islanding detection. Finally, using the PSCAD/EMTDC for simulation verification shows that the proposed method can rapidly and accurately detect islanding.