Abstract: Aiming at the stability control problem of grid-connected inverters in weak grids, a new phase-locked loop structure that is friendly to weak grid was first constructed. The novel phase-locked loop can add the necessary inertia and damping to suppress the problem of large fluctuations in frequency amplitude caused by sudden changes in the operating state of the inverter. The phase characteristics of the inverter equivalent output impedance were reshaped from the perspective of impedance, and the phase margin at the intersection frequency of the inverter equivalent output impedance and grid impedance was improved degree. The impedance reshaping control strategy was divided into two parts: the novel phase-locked loop impedance reshaping and the inverter control loop impedance reshaping. The phase-locked loop was reshaped by adding an adaptive resonant integral filter structure in the front stage of the novel phase-locked loop structure. The impedance shifts the phase-frequency characteristic of the inverter equivalent output impedance to a low frequency band, broadening the feasible range of the phase angle that can maintain the stability of the system. On this basis, the inverter control loop impedance is reshaped, so that the phase-frequency characteristic of the inverter equivalent output impedance moves in the direction of increasing phase angle, ensuring that the inverter grid-connected system has sufficient phase margin. The introduction of the impedance reshaping control strategy not only widens the grid-connected inverter’s adaptability to the grid impedance without sacrificing the bandwidth of the phase-locked loop, but also improves the steady-state and dynamic performance of its current control. Experimental measurements verify the analysis.