High current DC choppers and their operational benefits

The availability in recent years of larger power switching devices has brought about the development of larger power electronic circuits. These circuits were previously used in lower power applications. One such circuit is the DC-to-DC power converter, otherwise known as a DC chopper. The DC chopper system has many operational benefits over conventional diode or thyristor rectifiers, such as: low output ripple; fast dynamic response; near unity line power factor over its whole power range; minimal harmonic distortion of AC feeder without the use of harmonic traps; elimination of power factor correction equipment usually associated with thyristor rectifiers; higher system efficiencies over total output power range; and reduction in overall system size and cost. These benefits as well as the chopper topology are described in this paper.