Hey,
im required to design a buck converter that will step down the voltage to supply a piece of equipment.I also require to show the results of simulation of my circuit.
My circuit should meet the following specifications:
Vin=24V
Vout=18V
Max ripple compared to DC input=10%
load resistance=5 Ω
Switching frequency must lie between 50kHz to 200kHz
Assume ideal devices have been used!
ok..so to start of with, I no the circuit im required to design (not sure about the which switching device to choose yet).i have decided to use Pspice Student Version to simulate my circuit.
I have calculated:
Iout=Vout/Rload=18/5=3.6A
ΔI=0.1*3.6=0.36A
D=Vout/Vin=0.75
Now for continuous conduction mode:
we know that L=\(\frac{(Vin-Vout)*(D/Fs)}{Ir}\) whr Ir=ΔI
Now the issue is that i really cannot figure out how to choose Fs!!Once i choose Fs correctly, i can find the value for my filter inductor.
its mentioned in the ques that i can choose between 50kHz to 200kHz, but is there any appropriate logical way to selecting the Switching frequency?
I would also like to know whether its better to use a p/n type MOSFET or IGBT for my circuit and why!
thx
im required to design a buck converter that will step down the voltage to supply a piece of equipment.I also require to show the results of simulation of my circuit.
My circuit should meet the following specifications:
Vin=24V
Vout=18V
Max ripple compared to DC input=10%
load resistance=5 Ω
Switching frequency must lie between 50kHz to 200kHz
Assume ideal devices have been used!
ok..so to start of with, I no the circuit im required to design (not sure about the which switching device to choose yet).i have decided to use Pspice Student Version to simulate my circuit.
I have calculated:
Iout=Vout/Rload=18/5=3.6A
ΔI=0.1*3.6=0.36A
D=Vout/Vin=0.75
Now for continuous conduction mode:
we know that L=\(\frac{(Vin-Vout)*(D/Fs)}{Ir}\) whr Ir=ΔI
Now the issue is that i really cannot figure out how to choose Fs!!Once i choose Fs correctly, i can find the value for my filter inductor.
its mentioned in the ques that i can choose between 50kHz to 200kHz, but is there any appropriate logical way to selecting the Switching frequency?
I would also like to know whether its better to use a p/n type MOSFET or IGBT for my circuit and why!
thx