Abstract: Consensus algorithm is commonly used for distributed secondary frequency regulation control of multi-inverter parallel microgrid systems operating in isolation, which requires high real-time performance for communication between inverters. An improved consensus algorithm based on frequency compensation signal is adopted and an event trigger mechanism based on the frequency error crossing limit is designed, which can maintain the existing droop relationship between inverters and realize the secondary frequency regulation of a multi-inverter microgrid system operating in islanded mode at the same time. Meanwhile, based on this event triggered mechanism and Lyapunov function, the minimum trigger time lower bound is obtained, which completely avoids the phenomenon of infinite event triggers in a short period of time. Finally, MATLAB/Simulink is used to simulate the operation of an islanded microgrid system containing four inverters in parallel. The results show that the communication volume of the proposed method is reduced by more than 99% compared with the basic consistency algorithm used in the literature, and the minimum trigger time interval is extended to the order of tens of milliseconds. In the meantime, the dynamic performance of the microgrid system is better because the proposed method does not use the power differential signal.