The complex modeling process

unclear interaction impacts of control loops

and imprecise contribution of main circuits and control loops attract wide attention in the stability analysis of grid-tied power electronic devices. Therefore

the sources of stability misidentification are analyzed and a modified transfer function is proposed. The mis-estimated and over-estimated issues that are caused by the voltage fluctuation of the point of common coupling are solved. The applicable boundaries of the traditional simplified transfer functions are proposed. The mechanism by which system parameters such as the operating point and main circuit parameters

and control dynamics such as phase-locked loop and current loop affect system stability is analyzed. The influence of frequency-domain small-signal stability constraints on the maximum power transfer limit of grid-tied power electronic devices is explored. The identification method of the dominant influencing factors of the system and control dynamics on the maximum system power transfer is obtained. The proposed model and mechanism analysis are verified by the time-domain simulation carried on Matlab.