Active power filter with current balancing capability for two-phase systems

Two-phase residential installations have become very common in Ecuador since different policies prompt the users to replace gas stoves and water heaters by electric appliances. The addition of a second phase to the originally installed single-phase wiring is required to obtain 220Vrms. This fact carries an intrinsic unbalance since single- and two-phase loads coexist. In this paper a topology for an active power filter is proposed which is able of balancing of the currents leading to a balance in the active power in each phase. This added feature does not interfere with the capability of the active power filter for reactive power compensation. The proposed topology is tested by simulations for two-phase systems having phase voltages with 120° and 180° of difference.