Abstract: With plenty of parallel inverters connected to weak grid at the point of common coupling（PCC）, the impedance coupling interactions between the inverters and the grid are enhanced, which may cause high-frequency oscillation and further aggravate the system instability. A basic technique from the viewpoint of inverter output impedance was proposed to take into account the oscillation suppression, showing that the inverter output impedance should be designed relatively high at the oscillation frequency, while relatively low at other frequencies. On the basis of the proposed technique, two virtual impedances were added to be in parallel and in series with the original inverter output impedance, respectively. Thus, the high-frequency oscillation suppression method by two notch filters was proposed to increase the whole system damping.The implementation forms of the virtual impedances were presented by the proposed PCC voltage feedforward and grid-side inductor current feedback with two notch filters.Finally, experimental results were provided to verify the validity of the proposed control method.