Gamatronic Electronic Industries Ltd.
4
Power+ Technical Guide
2. FUNCTIONAL
OVERVIEW
2.1
UPS BASIC MODULE (10KVA / 8KW)
The UPS Basic Module is the core of the system, which comprises 1 to 10 identical parallel
modules depending on capacity requirements.
A general module view is shown in Figure
2-1. The module classic on-line double-conversion
type block diagram is illustrated in Figure
This design has proved to be very stable. No transfer time is required for the UPS to switch
from normal to backup mode; the load is supplied constantly by stable and clean power. A
Power Factor Correction (PFC)
is responsible for the low Total Harmonic Distortion (THD) and
unity Power Factor (PF) at the input.
The input voltage(s) is converted to a stable ±425V at the DC link.
This stage can maintain current sharing between the three input phases as well as among
other parallel units, because of the current sharing signal that it produces.
Figure
2-1: Single UPS Module- Front/Rear View
1
PFC is a feature included that reduces the amount of generated reactive power. Reactive power
operates at right angles to true power and energizes the magnetic field. Reactive power has no real
value for an electronic device, but electric companies charge for both true and reactive power resulting in
unnecessary expense.
In power factor correction, the power factor (represented as "k") is the ratio of true power (kwatts) divided
by reactive power (kvar). The power factor value is between 0.0 and 1.00. If the power factor is above
0.8, the device is using power efficiently. A standard power supply has a power factor of 0.70–0.75, and
a power supply with PFC has a power factor of 0.95–0.99.
