Project 1
ANS :-
1) Boost CCM
Calculation :-
Vi = 20-30 V, assume Vi = 25 V
Vo = 40 V
P = 600 W
Assume fs = 20 KHz
now, Vo/Vi = 1/(1-D) >> D = 0.375
R = (Vo)^2/P >> R = 2.67 Ohms
Il = Io = P/Vo >> Il = Io = 15 A
now, we Assume that 10% ripple in inductor current & 5% ripple in o/p voltage
delta Io = delta Il = 1.5 A
delta Vo = 2 V
from all value, L = Vi*D/fs*delta Il >> L = 0.3125e-3 H
C = D/ R*fs(delta Vo/Vo) >> C = 0.1404e-3 F
Simulation :-
for Vo ~ 40 V we take Vi = 26 V in simulation
Result :-
2) SEPIC CCM
Calculation :-
Vi = 30-60 V, assume Vi = 45 V
Vo = 45 V
P = 1 KW
Assume fs = 20 KHz
now, Vo/Vi = D/(1-D) >> D = 0.5
R = (Vo)^2/P >> R = 2.025 Ohms
Il1 = P/Vi >> Il1 = 22.22 A
Il2 = P/Vo >> Il2 = 22.22 A
now, we Assume that 10% ripple in inductor current & 5% ripple in o/p voltage
delta Il1 = delta Il2 = 2.22 A
delta Vc1 = delta Vo = 2.25 V
from all value, L1 = Vi*D/fs*delta Il1 >> L1 = 0.5063e-3 H
L2 = Vi*D/fs*delta Il2 >> L2 = 0.5063e-3 H
C1 = D/ R*fs(delta Vc1/Vc1) >> C1 = 0.2469e-3 F
C0 = D/ R*fs(delta Vo/Vo) >> C0 = 0.2469e-3 F
Simulation :-
for Vo ~ 45 V we take Vi = 47 V in simulation
Result :-
3) Buck-Boost CCM
Calculation :-
Vi = 300-600 V, assume Vi = 450 V
Vo = -450 V
P = 2 KW
Assume fs = 20 KHz
now, Vo/Vi = -D/(1-D) >> D = 0.5
R = (Vo)^2/P >> R = 101.25 Ohms
Il = Io = -Vo/R*(1-D) >> Il = Io = 8.89 A
now, we Assume that 10% ripple in inductor current & 5% ripple in o/p voltage
delta Io = delta Il = 0.889 A
delta Vo = -22.5 V
from all value, L = Vi*D/fs*delta Il >> L = 12.65e-3 H
C = D/ R*fs(delta Vo/Vo) >> C = 4.938e-6 F
Simulation :-
for Vo ~ -450 V we take Vi = 441.5 V in simulation
Result :-
