Experimental Investigation Based Power Quality Assessment Of The Single- And Three-Pulse Diode Rectifiers

The single- and three-pulse diode rectifiers constitute the most fundamental of the single- and three-phase topologies respectively, pertaining to uncontrolled ac to dc conversion. Their nomenclature is based on the pulse number (n) they provide at the dc output which is essentially the number of dc voltage notches corresponding to one time period of the input ac source. From the topological perspective, they are referred to as single-phase half-wave rectifier and three-phase half-wave rectifier respectively and are the building blocks of rectifier topologies with higher pulse number. Rectifiers with pulse number greater than or equal to three (n$\geq$3) are classified as multipulse rectifiers that comprise series or parallel cascade of these topologies. Usually, three-phase rectifier topologies alone are classified as unidirectional multipulse ac-dc converters among improved power quality ac-dc converters, however, it is noteworthy that the three-phase half-wave rectifier is a parallel cascade of three single-phase half-wave rectifiers. Comprehension and estimation of the power quality indices of these two basic topologies including harmonoic content of the line currents, least order harmonic, power factor, distortion factor, displacement factor, and THD on the ac side and ripple factor, crest factor, and form factor on the dc side provide useful insights into the multipulse rectifiers. In this paper, the power quality assessment of the two basic topologies using MATLAB software and experimental investigation based data are presented.