Control of integrated utility grid plays important role, as renewable energy sources are rapidly increasing with installation of different Distributed Generation (DG) systems. A lot of issues are arising during the operation like interruption, disorder and uncertainty. One of the situations is islanding necessary to secure humans and converter devices, working in interconnected electrical energy sources environment. Parameter of grid system like voltage and frequency are taken to identify these situations and control through converter signals. Fuzzy sets are used in updating with Rate of Change of Variable Voltage (RCVV), Rate of Change of Variable Frequency (RCVF). Hence leads to proposed variable inverter pulses, in method of Islanding Detection. Adaptive island algorithm is developed with fine tuned control vector used to recognize Island events in integrated utility grid. Variable inverter pulse has been considered for isolating DG at Island completion. This paper presents fuzzy based island helps to overcome existing challenges existing challenges of rate of change in voltage and frequency and motivate to better recognition. Outcomes of the paper to update inverter pulses as function of change in voltage and frequency at Point of Common coupling (PCC) with different conditional operating modes of system. Effective outcome of proposed is mainly with fuzzy control for both RCVV, RCVF of existed methods of islanding with voltage and frequency variations.