Novel line conditioner with voltage up/down capability

In this paper, a novel pulsewidth-modulated line conditioner with fast output voltage control is proposed. The line conditioner is made up of an AC chopper with reversible voltage control and a transformer for series voltage compensation. In the AC chopper, a proper switching operation is achieved without the commutation problem. To absorb energy stored in line stray inductance, a regenerative DC snubber can be utilized which has only one capacitor without discharging resistors or complicated regenerative circuit for snubber energy. Therefore, the proposed AC chopper gives high efficiency and reliability. The output voltage of the line conditioner is controlled using a fast sensing technique of the output voltage. It is also shown via some experimental results that the presented line conditioner gives good dynamic and steady-state performance for high quality of the output voltage.