Abstract：The final aim of the control system of grid-connected inverter is to track the reference current. So it is needed to predict the reference current according to the previous two or three switching periods. Due to the mismatch of the model inductance and actual inductance, the impact had on the stability of system for different control algorithms will be different, namely on the premise that the system be stable, different algorithm differs in the tolerance of inductance mismatch. On the basis of analyzing stability of single phase grid-connected inverter control system, advantages and disadvantages of each kind of predictive current control algorithms were compared. The fundamental reason why the control effects differed from each other was indicated. And an improved predictive current control algorithm was proposed that changes the aim of current error from the current difference of previous two periods to a specified one. The proximate calculation of intermediate variable is decreased and the stability of algorithm is improved. The tolerance of inductance dismatch is largely raised. Better stability margin is achieved relative to conventional methods. In the end the superiority is testified through simulation model and experimental platform.
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2010, Vol. 25 
