1. Dr. Unnikrishnan P.C. Professor, EEE
EE305 Power Electronics
Dr. Unnikrishnan P.C.
Professor, EEE

2. Buck-Boost Regulator
The buck operation or the boost operation depends on the duty ratio of the chopper

3. Buck-Boost Regulator The output voltage is of reverse polarity
For 0 <  < 0.5 , VO<VS ,the circuit functions as a Buck regulator
For 0.5<  < 1 , VO>VS , the circuit functions as a Boost regulator
The source is never connected directly to the load- indirect regulator
The source current flows only when the switch is turned ON, hence the source current is discontinuous.

5. Buck-Boost Regulator Analysis

6. Buck-Boost Regulator Analysis

7. Buck-Boost Regulator Analysis
Current Ripple

8. Buck-Boost Regulator Analysis

9. Buck-Boost Regulator Analysis

10. Buck-Boost Regulator Analysis