Rockwell Automation SA3000 High Power Modules - Manual (Page 13)

Mechanical/Electrical Description 2-1
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Mechanical/Electrical Description
This chapter provides an overview the SA3000 Power Module’s main components and
their mechanical and electrical characteristics.
2.1 Mechanical Description
The High Power SA3000 Power Modules are variable-voltage, variable-frequency
inverters that are housed in protective sheet metal enclosures. The Power Modules
are supplied in single, double, and triple bay cabinet configurations, depending upon
the current rating. See figures 2.1 to 2.3. Power Module dimensions are shown in
figures 3.1 to 3.3.
2.1.1 Power Module Components
The Power Modules have the following main components:
Phase modules
Each Phase module contains four semiconductor IGBTs (insulated gate bi-polar
transistors). IGBT pairs are switched on and off by the integrated Snubber/Gate Driver
module to provide modulated phase voltages (U,V,W) to the motor. Fuses and
thermostats are provided to protect the IGBT modules.
Snubber/Gate Driver Module
Each Snubber/Gate Driver module, mounted on the IGBT phase module, receives
gating signals via fiber-optic cabling from the GDI module(s) in the PMI rack and
translates the signals into the appropriate voltage and current levels to turn the IGBTs
on and off. Feedback, indicating the integrity of the phase module and IGBTs, is then
sent back to the GDI module(s).
This module also provides snubber circuitry (resistors, diodes, and capacitors) to
control voltage overshoot and undershoot when the IGBTs are switching.
Fiber-Optic Communication
Fiber-optic cabling is used to transmit gate driver signals from the Gate Driver
Interface (GDI) module.These signals are used to turn the IGBTs on and off. IGBT
module feedback status information is sent via the fiber-optic cabling back to the GDI
module(s) in the PMI rack. Fiber-optic cabling is immune to electromagnetic and radio
frequency interference (EMI/RFI) and eliminates ground loops. For more information
on fiber-optic cabling refer to the Distributed Power System Fiber-Optic Cabling
instruction manual (S-3009).