08-01-2013, 02:55 PM
REGULATION CHARACTERISTICS OF BUCK-BOOST CONVERTER
AIM:
To determine the closed loop response of the Buck-Boost converter and plot the regulation characteristics.
APPARATUS REQUIRED:
1. VSMPS-07A Trainer
2. Pulse patch chords
3. (0-30V) DC supply
4. CRO
FORMULA:
Output voltage V0¬ = (-D / 1-D) Vs Volts
Where V0 = Converter Output Voltage, Volts
Vs = Converter input voltage, volts
D = Duty Cycle (ton / T)
THEORY:
The Buck Boost is a popular non-isolated, inverting power stage topology, sometimes called a step up/down power stage. The Buck boost power stage is chosen because the output voltage is inverted from the input voltage and the output voltage can be either higher or lower than the input voltage. However the output voltage is opposite in polarity from the input voltage. The Buck Boost converter circuit consist of MOSFET switch Q, inductor L, diode D, filter capacitor C and load resistor R.
CONNECTION PROCEDURE:
• Connect P8 of PWM generator to PWM input of Buck-Boost converter circuit.
• Connect P4 of Buck-Boost converter circuit to P7 of PWM generator.
• Set switch SW1 to downward direction to select the closed loop operation.
• Connect (0-30V) DC regulated power supply across P1 and P2 terminals of the trainer module and set the voltage at 15 V.
RESULT:
Thus the closed loop response for Boost/Buck operation of Buck-Boost converter of Line/Load regulation was determined.
1. The output voltage is maintained at ------ V with the input voltage from ------- V to ---------- V for boost mode of operation.
2. The output voltage is maintained at ------ V with the input voltage from ------- V to ---------- V for buck mode of operation.