Abstract: In this paper,a current control strategy of the PV grid-connected inverter based on Kalman observer is presented for the time delay compensation. Firstly,the state of the inverter is one-step forecasted by the improved Kalman observer to obtain the predicted value of the state variable. The time delay compensation is implemented through the state feedback of predictive variable,and the active damping of LCL filter is obtained at the same time. Comparing with the Luenberger observer,the Kalman observer does not require complex zero-pole configuration so as to simplify the observer design. Furthermore,an appropriate outer loop is used to achieve the zero steady current error. Finally,Detailed simulation and experiment results are presented to show the feasibility of the proposed control strategy.