Abstract: With the large scale distributed generation units and flexible controllable loads interfaced into the power grid through the power electronic devices, harmonic oscillation caused by the interaction among distributed sources, the utility grid and load with complex characteristic occurs frequently. In this paper, IEEE 9 regional microgrid was taken as the research object. Firstly, the influence of diversified local load types on the impedance characteristics of the grid side was analyzed with Bode diagram. And the generalized Nyquist criterion was used to predict the high frequency resonance problem in various loads. The increase of capacitive local load will would lead to the essential change on the impedance characteristics of the traditional inductive weak grid. On this basis, aiming at the diversified operation characteristics caused by the access of diversified local loads to the power grid, a kind of adaptive impedance amplitude reshaping scheme for diversified local loads was proposed through the grid side impedance characteristic discrimination, and considering the multi position feedback nodes. At the same time, the feedforward gain was selected according to the stability improvement and compensation depth. The scheme was implemented by software, which does did not need to add additional detection circuit and hardware damping means, and didoes not increase system cost and loss. Finally, the correctness of the above research and the feasibility of the proposed scheme were verified by simulation and RTDS hardware in loop experiment.