Abstract: Weighted average current（WAC） control method is widely used in grid-connected inverters because of its order reduction characteristics. However, the impact of digital control delay on grid-inverter system has not been fully considered in the traditional WAC control methods. The analysis in this paper shows that the phase lag introduced by control delay makes the traditional WAC control method no longer have the characteristics of loop order-reduction, and leads to a reverse resonance peak in loop gain varying with the grid impedance, which puts the grid-inverter system at risk of instability. In order to solve this problem, the high-robustness WAC control strategy based on lead compensator was proposed in this paper, which used the lead compensator introduced in feed-forward channel to compensate the phase lag in the frequency range of the reverse resonant peak, so as to acquire the characteristic of loop order-reduction and the adaptability to weak grid. The comparative analysis and experimental results show that the proposed control strategy can retain the reduced-order advantages of the traditional weighted average current control, and has strong adaptability to weak grid meanwhile.