A hybrid parallel active filter in off-line up system with proposed control strategy

A hybrid parallel active filter in offline UPS system with proposed control strategy is presented, the system contain an inverter acting as an active filter that has two modes of operation, the first is to supply the non-linear load while compensating for the current harmonics and the second is to remove the stress from the back up battery while supplying the load when the main supply goes off. The proposed design is presented with the control strategy and with a full simulation results.