Figure 2-5: Pfc Control Scheme - Gamatronic POWER PLUS Technical Manual

Gamatronic Electronic Industries Ltd.
required for the proper operation, an inner current loop for maintaining a correct wave shape
and an outer voltage loop to ensure a correct DC output level.
The voltage sample (k*Vin) is multiplied by the error voltage from a common voltage feedback
amplifier (Integrator). The result is than compared to the actual sampled phase current which
forces the current amplifier current to follow the phase input voltage. The output of the
integrator is connected to a current sharing bus causing all other modules to be connected to
this bus via the same resistor. This ensures that all the multipliers of each UPS module receive
the same input and all that modules are equally loaded.
K1*V1
PH1
NEUTRAL
K1*V2
PH2
NEUTRAL
K1*V3
PH3
DC
NEUTRAL
share
bus
Power+ Technical Guide
Current
MULT
Amplifier
Comparator
+
-
Current
MULT
Amplifier
Comparator
+
-
Current
MULT
Amplifier
Comparator
+
-
Verror
Integarator

Figure 2-5: PFC control scheme

PWM POWER
+
BLOCK
-
Triangle
PWM POWER
+
BLOCK
-
Triangle
PWM POWER
+
BLOCK
-
Triangle
K2*Vout
Vref
Vout (DC)
7