Improvement of current regulation of line-current-detection-type active filter based on deadbeat control

A new control scheme for the line-current-detection-type active filter (AF) is proposed to improve the current regulation capability based on the digital deadbeat (DB) control. The current control scheme is achieved by controlling the intermediate voltage of the inverter output filter so that the AF output current is regulated using the DB control law for the calculation of the pulsewidth of the pulsewidth-modulation inverter. In the proposed scheme, the current regulation performance is improved to be much better than the conventional one. The control method, mathematical analysis, the simulation results, and the experimental results are presented in this paper.