Reactive phase angle error island detection method based on frequency positive feedback

The invention discloses a reactive phase angle error island detection method based on frequency positive feedback. The difference value between microgrid standard frequency and microgrid actual frequency serves as input for computing reactive disturbance and feedback current phase angle deviation, the feedback current phase angle deviation serves as input for computing energy storage output reactive power, the sum of reactive disturbance and the energy storage output reactive power serves as input for computing load reactive power, the load reactive power influences microgrid frequency in a feedback mode, and accordingly frequency of a microgrid gradually deviates in the island state till the frequency goes out of limit. The detection method has the advantages of being high in detection speed, small in current harmonic and the like.