Service manual

5. PRINCIPLE OF OPERATION
5.1 Functional Block of The Product
As a true online UPS, the product employ a double conversion topology, comprise following
functional blocks, as shown in Figure 5.1.1
PFC / Rectifier Inverter
I/ P EMI
FILTER
Bypass
Power Supply
(SPS)
Controller
O/P EMI
FILTER
AC
AC
DC
DC
Battery
Charger
Battery
Booster
DC
DC
I/ P Mains
O/P
Battery
Ventilation
&
Chassis
User Interface
Figure 5.1.1 Function block Diagram of the product
In which:
The controller block controls the operation of the whole UPS, the controller block also provides
communication interface for receiving and executing command from user via the panel or a preset
protocol.
The AC/DC module, called also PFC/rectifier, belongs to input stage of the UPS. The AC/DC
converter block converse the AC mains input power into a pair of stable DC power storing on the
DC-BUS. In means time, Power Factor Correction is performed, the input current tracking the
input voltage waveform, and the input power fact can very close to 1, achieve maximum efficiency
and product lowest power pollution to the power supply system.
The DC/DC module, called also Battery Booster, is another part of input stage, used to converse
the low level DC power into higher level and more stable DC power, storing on the DC-BUS also.
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