Please do 3 and 4.
In a Buck dc-dc converter that is operating in the steady state under the following conditions:
Vin (V): 42
P.W: VV
Switching frequency (f): 400 kHz
Duty-ratio (D): 0.3
150
Assume ideal components and continuous conduction mode. If the output voltage (Vo) is kept constant while the input voltage (Vin) is allowed to vary 10% from the value in the above table, and the output power (Po) can vary from 30% to 100% of the value in the above table, find the minimum value of the inductance that guarantees continuous conduction. (Hint: When the output voltage is kept constant, use the Pomin condition to determine the minimum inductance value to guarantee CCM.)
Vo: 21 minls
2. Use the inductance of about 115% of the minimum value obtained from Problem 1 to find the average output voltage (Vo.p-p) neglecting the capacitor's ESR (8f).
3. Use the inductance of about 115% of the minimum value obtained from Problem 1 and the capacitance of about 110% of the value obtained from Problem 2. At the following four combined conditions: minimum and maximum input voltages, minimum and maximum output powers, find the corresponding operating quantities:
Input voltage Vin (V)
Output power P (W)
Duty-ratio D
Inductor Average Output Average output voltage input ripple current ripple current A) 1A Vop-p Iim(A)
Vinmin = Vinmax =
Pomin =
Pomin = Pomax =
4. Use the above parameters to perform simulations (using MATLAB/Simulink) for the four conditions in Problem 3. Plot the simulation results and compare them with those of the calculation in Problem 3.