For the distributed grid system encountered island effect, this paper first introduces the traditional technique of active islanding detection method and sliding mode frequency shift detection method, and make the corresponding simulation verified and compared against the blind spot of classic island detection technology in the detection limit is proposed which is based on intermittent chaos theory islanding detection technology, and conducted a parameter selection and simulation results show that the method effectively solves the distributed grid system and network voltage mutation case system protection issues, the program for the distributed grid system to ensure safe and stable operation, improve system reliability, there is some reference value.