Active Power Filters: A Comparative Analysis of Current Control Techniques for Four-Leg Full-Bridge Voltage Source Inverters

This paper  presents a  comparative  analysis between three current control techniques used  to  obtain the firing pulses of Four-Leg Full-Bridge  Voltage Source Inverters  (FLFB-VSI),  for   shunt   active   power  filters applications. The discussed techniques correspond to the Delta Modulation, the Proportional Integral (PI) regulator and the Deadbeat   controller.  The main purpose is to analyze the performance of each technique in the tracking of unbalanced and distorted current references including homopolar sequence components. The algorithms performance  is  evaluated  through  some  simulations  in ATP  and  the  comparative  analysis  is  based  on  some criteria such as the maximum steady state error and the effective error of the current generated by the inverter.  It can be concluded that the Deadbeat controller presents the lowest tracking error of the three techniques for the FLFB-VSI topology.