Ups Working Principle; Ups System Block Diagram; When Utility Is Normal - Ablerex MSRT-Pro 1KVA User Manual

5.

UPS Working Principle

5.1. UPS System Block Diagram

Figure 5.1 above illustrates the True On-Line Double Conversion architecture
of the UPS system. The major modules consist of：
1) An AC to DC power converter (Rectifier) with PFC control circuit
2) A DC to AC power high frequency inverter
3) An Intelligent Battery Charger
4) A bank of stationary maintenance-free batteries
5) A DC to DC push/pull converter control circuit
6) A Static Bypass Loop
7) Input & Output EMI Filter
The table below provide a summery guide to the UPS operating modes
against the Utility AC Power Source conditions
(fig 5.1)
36
Utility
UPS Operating Modes
Conditions
Rectifier convert AC to DC, battery
charging, Inverter convert DC to AC
Utility Normal
and supply to loads with clean & stable
power.
Rectifier and charger stop operating，
Battery discharge via DC~DC boost
Utility Abnormal
circuit and supply to Inverter. Loads
(under or over
continue to receive supply from
voltage) / Absent
Inverter. Alarm buzzer beeps, UPS now
on battery mode.
Rectifier and charger stop operating，
Battery discharge via DC~DC boost
Utility
circuit and supply to Inverter. Alarm
Abnormal/Absent,
buzzer beeps with quick & short
Battery low voltage
succession, indicating battery power
low and Inverter may stop supply soon.
Paragraph 5.2 ~ 5.7 below provide detailed descriptions of the UPS operating
principle

5.2. When Utility is Normal

The working principle of the UPS under Utility normal condition is illustrated as
follows：
When Utility is normal, the AC source is rectified to DC, which fed into the inverter.
The charger will turn on automatically to charge batteries. The inverter revert the
DC to a cleaned and pure AC to supply energy to the load connected. The
.
, LEDs illuminated
LEDs Display
indications
, , LEDs
remain illuminated
LED off, LED
illuminated
LED off, &
LED illuminated.
Fig 5.2
37
,