Project 3

Aim :Design and simulation of Buck converter for Auxiliary load in EV

Given

• Input voltage is 48V, Output voltage is 12 V
• Load current is 10A

The calculations are done on the to find the values of L C and R

Vin=D*Vout

where Vin- input voltage

Vout- output voltage

D= duty ratio

D= Vin/Vout

=12/48=0.25

Finding inductance value

L=Vout(Vin-Vout)/ΔIl*fs*Vin

Ripple current ΔIl=0.2 to 0.4% of load current=0.4*10=4A

Then L= 12(48-12)/4*1000*48=2.25*10^-3

Finding capacitance

C=ΔIl/8*fs*Vout

=4/8*1000*12=4.16*10-5

Finding value of resistor

R=Vout/Il

=12/10=1.2ohms

The blocks used are

PWM generator

Used to provide pulses to the MOSFET

MOSFET

It is used to control the voltage in the circuit

Diode

Used as free wheeling diode in the circuit

Resistor

The load used is resistor load.

Value of R=1.2ohms

Capacitor

Used to give capacitance in the circuit

C=4.16*10-5

Inductor

Used to provide the purpose of inductor in the circuit.

L=2.25*10^-3

Switching frequency is given as 50kHz

Circuit

Buck converter:

It is used to step down voltage from higher to lower value.

From the output it is observed the aim has been accomplished by converting Input voltage of 48V to 12V