Control of a single-switch three-phase rectifier operating in continuous conduction mode

In many power electronics power supplies, power converters connected to the network are diodes or thyristors bridges, which cause a great deal of harmonic currents. The increasing number of power converters used today may lead to high harmonic levels on the network, which is deemed a potential problem for electricity supply quality and the proper operation of electrical equipment. This explains the appearance of standards aimed at reducing the harmonic emission of power supplies. In terms of the three-phase power converters which are typical of medium- and high-power applications, the PWM rectifier is a well-known and efficient way of obtaining a good power factor. It is expensive, however, and the challenge is now to find more economical devices which would help the spread of such nonpolluting power converters. In response, this paper thus describes a single-switch, three-phase PWM rectifier. This power converter operates in continuous conduction mode in order to avoid the voltage or current overloads which are inherent to discontinuous conduction mode operation.