The standard version of rectifier, is an a.c./d.c. static
converter that uses thyristors bridges for the conversion.
The thyristors rectifier uses the phase control technique. This
way it is possible to obtain the stability required in the
output d.c. voltage, in case of grid voltage and load variations,
as well as other features as output current limitation or
battery charge current limitation.
6 PULSES RECTIFIERThere are two types of 6 pulses
rectifiers:
Three phase bridge of full wave
This type of three phase rectifiers made by 6 thyristors
bridges is characterised by the high utility factor of the
transformer, which, altogether with the high reliability and
fast response speed of the thyristors bridges, make of it a very
robust system.
6 phase rectifier bridge with 6 thyristors and interface
transformer
It is made up of a parallel connection of two half wave
bridges with three thyristors each one and an interface
transformer.
This connection is used in rectifiers of high currents and low
voltages, since it allows reducing the rms current circulating
for each power semiconductor. This way the losses are decreased
and so are the sizes of the semiconductors and heatsinks,
increasing the efficiency of the conversion. |
12 PULSES RECTIFIER
This rectifier is a a.c./d.c. static converter made up of two three
phase bridges of 6 thyristors each, shifted between them and coupled in
parallel with an interface transformer.
This connection is used in rectifiers of high powers with high output
current values in order to reduce the distortion of the a.c. current
wave absorbed by the grid, which is 12% with this configuration.
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