Grid-connected inverters with LCL filters can decline high-frequency harmonics; however, grid-connected inverters are usually coupled with digital control, which makes the system subject to delay and influences the frequency characteristics of the system’s transfer function, placing more stringent requirements on the stability of the grid-tied inverters. Moreover, in weak grid with high impedance, the stability of the inverter is impaired, which in turn leads to destabilizing divergence. To boost the stability of inverter in case of weak grid with fluctuating impedance, a hybrid damping strategy is presented in this article, which analyzes the stability of the system in the range of grid impedance fluctuation under the control delay and identifies the stable region by stability criterion, and rationally designs phase lag compensator, the overshoot compensator, and the proportionality parameter of the feedback loop. The improved system complies with stability judgement under weak grid condition of varying impedance, which can guarantee that LCL-type grid-linked inverter maintains stable operation. Finally, Simulink simulation results prove the feasibility of the scheme.