Figure 4. Path of current through the UPS in the double conversion mode
A Static
switch
1 Bypass in-
put
Main power flow
B Rectifier
2 Rectifier in-
put
Energized
C Inverter
3 Output
De-energized
D Battery con-
verter
4 Battery
breaker
Trickle current
E Battery
Closed
Open
Three-phase AC input power is converted to DC using a multilevel converter
with IGBT devices to produce a regulated DC voltage to the inverter. The UPS
status indicated on the display is
Unit Online
and the UPM status is
Active
.
The battery converter derives its input from the regulated DC output of the
rectifier and provides regulated charge current to the battery. The battery is
always connected to the UPS and ready to support the inverter should the utility
input become unavailable.
The inverter produces a three-phase AC output to the critical load. The inverter
uses multilevel converter technology with IGBT devices and pulse-width
modulation (PWM) to produce a regulated and filtered AC output.
If the utility AC power is interrupted or is out of specification, the UPS
automatically switches to the battery mode to support the critical load without
interruption. When utility power returns, the UPS returns automatically to the
double conversion mode.
Eaton 93PS UPS 8–40 kW
User's and installation guide
©
Eaton Corporation plc 2016. All rights reserved.
Revision: 003
Document ID: P-164000493
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