Positive buck boost converter

A positive instead of a negative output buck boost is studied. P-control is just used.

the model has the following parameters and specifications. It’s operating in continuous mode, with buck mode (Vin=110 – 200), and Buck – Boost mode (110 – 50V). Buck-boost transition technique was used at 110 to 90Vinput so that a smooth transition from buck to buck-boost mode can be achieved.

Table 5 Simulation Parameters
Vin 50 – 200V
Vout 100V +/- 5%
Pout 1000W
Freq. 10kHz
L 10mH
Cout 1000uF
R sense 0.01 ohm
Rload 10 ohms

There are 3 operation modes of this model namely buck mode, buck-boost transition mode and full buck-boost mode. Each modes has its respective ramp generator which are switched over depending on the Vin levels and regulates the Vout up to ±5%.

Table 6 Simulation Modes
Modes Vin
Buck Mode 110 ≤ Vin ≤ 200V
Buck-boost transition mode 90 ≤ Vin ≤ 109
Full buck boost mode 50 ≤ Vin ≤ 89