Power Electronics and Motor Drive Systems

4.5. Three-Phase Bridge Diode Rectifier

Fig. 4.10(a) presents the power circuit of the three-phase bridge diode rectifier. It is one of the most well-known and simplest rectifying topologies used for high-power applications. The diodes are numbered according to their conduction sequence. Diodes D₁, D₃, and D₅ are used for the rectification of the positive half-waves of the input sources (v_aN, v_bN, v_cN) of the rectifier and diodes D₄, D₆, and D₂ for the negative ones. At any instant the diode from the upper group with the highest positive anode voltage is conducting and at the same time the diode from the lower group with the highest negative cathode voltage is conducting. Therefore, every time a pair of diodes is conducting one from the upper ...