Editing Rectifier (section)

==== Three-phase, full-wave circuit using center-tapped transformer ====
[[File:6 phase half wave rectifier.png|thumb|300px|Controlled three-phase full-wave rectifier circuit using [[thyristor]]s as the switching elements, with a center-tapped transformer, ignoring supply inductance]]
If the AC supply is fed via a transformer with a center tap, a rectifier circuit with improved harmonic performance can be obtained. This rectifier now requires six diodes, one connected to each end of each transformer secondary [[winding]]. This circuit has a pulse-number of six, and in effect, can be thought of as a six-phase, half-wave circuit.

Before [[solid state (electronics)|solid state]] devices became available, the half-wave circuit, and the full-wave circuit using a center-tapped transformer, were very commonly used in industrial rectifiers using [[mercury-arc valve]]s.<ref name="Rissik1941">{{cite book|author=Hendrik Rissik|title=Mercury-arc current convertors [sic] : an introduction to the theory and practice of vapour-arc discharge devices and to the study of rectification phenomena|url=https://books.google.com/books?id=S4MhAAAAMAAJ|year=1941|publisher=Sir I. Pitman & sons, ltd.}}</ref> This was because the three or six AC supply inputs could be fed to a corresponding number of anode electrodes on a single tank, sharing a common cathode.

With the advent of diodes and thyristors, these circuits have become less popular and the three-phase bridge circuit has become the most common circuit.