Use litspice or matlab samscope. Design a buck converter to perform a controlled

Photo of author

By admin

Use litspice or matlab samscope. Design a buck converter to perform a controlled pre-charge for a 10,000μF capacitor
bank. The input voltage is 300Vdc. The charging current should be 1A ± 100mA. The
switching frequency is 25kHz. Hint: Remember the maximum ripple theorem for a buck
converter. You can assume all switches are ideal. Provide the required voltage and
current rating for the switch and diode, and the inductance of the inductor.
2. Implement your converter in Simulink with a PI controller. When the output voltage
reaches 95% of its final value, the buck converter should shut off. Tune your PI
controller. Provide four figures:
a. The full model, with gains noted.
b. The output voltage for the full charging process.
c. The inductor current for the full charging process.
d. The inductor ripple current when the load voltage is at 150Vdc.
3.we discussed how a buck converter in discontinuous operation may
have problems if the switch is operated from a bootstrap supply. Explain why this will
NOT happen with a synchronous buck converter (i.e. a bidirectional DC-DC converter in
buck mode).
4. For the Cuk converter, derive the transfer function for the circuit using the continuity of
the capacitor voltage in the center capacitor (i.e. the average capacitor current must be
0A). Hint: What is the relationship between the inductor currents, and the input and
output currents? How are the input and output currents and voltages related with respect
to input and output power?
side note: your buck converter is the precharge circuit. Basically, you have a simple buck converter with no load except a huge output capacitor. The buck converter controls the charging current.
Don’t bother with any input capacitance.