08-01-2013, 02:56 PM
REGULATION CHARACTERISTICS OF FLYBACK CONVERTER
AIM:
To determine the closed loop response of the Flyback converter and plot the regulation characteristics.
APPARATUS REQUIRED:
5. VSMPS-09A Trainer
6. Pulse patch chords
7. (0-30V) DC supply
8. CRO
FORMULA:
Output voltage V0¬ = (D / 1-D)(N2/N1) Vs Volts
Where V0 = Converter Output Voltage, Volts
Vs = Converter input voltage,volts
D = Duty Cycle (tON / T)
N2 / N1 = Transformer turns ratio.
THEORY :
The flyback converter is a negative output step-up converter (i.e) it is an isolated version of the buck-boost converter. The inductor of buck-boost converter has been replaced by a flyback transformer. The input dc source Vs and switch Q are connected in series with the transformer primary. The diode D and the RC output circuit are connected in series with the secondary of flyback transformer. The circuit diagram of flyback converter is shown below.
CONNECTION PROCEDURE :
1. Connect P8 of PWM generator to PWM input of Flyback converter circuit.
2. Connect P4 of Flyback converter circuit to P7 of PWM generator.
3. Set switch SW1 to downward direction to select the closed loop operation.
4. Connect (0-30V) DC regulated power supply across P1 and P2 terminals of the trainer module and set the voltage at 30 V.