Week-6 Challenge: EV Drivetrain
1Which types of power converter circuits are employed in electric and hybrid electric vehicle?
> AC to DC conveter
> DC to DC conveter
> DC to AC conveter
2. An Electric Vehicle's powertrain with 72V battery pack in shown in the diagram below. The duty ratio for acceleration operation is 'd1' and for the braking operation the duty ratio is 'd2'.
Solution:
Here, Armature voltage(v)= 72 V
Rated armature current= 400 A
Ra= 0.5Ω, KΦ= 0.7 Volt second
Chopper Switching frequency= 400 Hz
the speed torque formule is as below,
Tm=vk/Ra - k^2w/Ra
Tm= ((72*0.7*0.7)/0.5)-((0.7)^2*w)/0.5
Tm= (50.4/0.5)-(0.49w/0.5)
Tm= 70.56-0.98w
So, now we need to equate the both equation
Tm=Tl
24.7+0.0051w^2=70.56-0.98w
0.0051w^2+0.98w-45.86=0
As per quadratic equation,
X=(-b± √ b^2-4ac)/ 2a
which can be writen as,
w= (-0.98± √(0.98)^2-4(0.0051)*(-45.86))
w=(-0.98±1.377)/0.0102
w=+38.99 & w= -231
The steady state speed is 38.99 rad/sec.
3.Develop a mathematical model of a DC Motor for the below equation using Simulink.
ω= V/Kϕ -Ra/Kϕ^2 .T
Simulink model:
Result:
