Control of 4-leg active power filter for reactive power and unbalance compensation

In this paper, indirect control theory is proposed for a 4-leg shunt active power filter (SAPF) to compensate reactive power and balance the load currents. The control for the fourth leg is made different from the other authors by using 0 as the neutral current reference. All simulations performed by using Matlab-Simulink show the effectiveness of the proposed solution.