A deadbeat control algorithm based on repetitive predictor theory for three-level active power filter

Due to the limitation of voltage capability and current capability of power devices, it is very difficult to handle nonlinear loads for the traditional active power filter(APF) with two-level inverter in high voltage high power grid. Three-level inverter has been put into research and practical use for years especially in high voltage high power grid. This paper researches a deadbeat control algorithm based on repetitive predictor theory for three-level active power filter. In this paper, canceling the delay of one sampling period and providing the predictive value of the harmonic current is the key problem of the deadbeat control. Based on this deadbeat control, the predictive output current value is obtained by the state predictor. The state predictor remedies the delay of one sampling period in this digital control system. The predictive harmonic command current value is obtained by the repetitive predictor synchronously. The repetitive predictor can achieve the prediction of the harmonic current accurately, thus improve the overall performance of the system. Experimental result confirms the validity of the proposed approach.