Power Electronics SD750FR, Hardware And Installation Manual

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SD750FR POWER ELECTRONICS
36
POWER CONNECTION
EN
Topology
The following figure shows the upgraded power electronics for the SD750FR.
SD750FR is based on an active in feed topology that substitutes the thyristor diode rectifier by a
controlled Isolated Gate Bipolar Transistor (IGBT) bridge. This bridge is operated by its own control and
power board that creates an almost sinusoidal input current wave. This technology reduces the THDi
with
the highest efficiency and space savings. Furthermore, the Cos φ = 1.0 is adjustable and will be
kept at any load condition. Forget the capacitor bank installation, additional bill charges and transformer
and wiring overheating.
The active front end technology substitutes the multipulse drives and passive filters. The multipulse
solutions have higher installation cost by means of special transformers and wiring requirements, no
cosine phi control, filtering features load dependant, higher input voltage drops and no regeneration
capacity.
The following charts show the input voltage and current waveforms differences between a 6-pulse drive,
18 pulse drive and SD750FR drive. It is shown the THDi reduction in the input current waveform for
SD750FR drive.