Week-6 Challenge: EV Drivetrain

1. Which types of power converter circuits are employed in electric and hybrid electric vehicle?

Types of Power Converter Used in Electric and Hybrid Vechicles
S:NO	Types
1	Diode rectifier.
2	AC-DC converters (controlled rectifier)
3	AC-AC converters (AC voltage controller)
4	DC-DC converters (DC choppers)
5	DC-AC converters (Inverters)
6	Static switches.

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'.

Here i have Attached Excel for Vechicle Speed- Torque Excel. I Explain Step by Step Mathematical Calculation.

3. Develop a mathematical model of a DC Motor for the below equation using Simulink.

ω= V/Kϕ -Ra/Kϕ^2 .T

Please find the attached screenshot for mathematical model of a dc motor using Simulink.

4. Explain in brief about author’s perspective.

Following within the windings to produce a torque interaction between the rotor and stator. While Rotate Contionusly stator current be contiously Varied and orque remains
constant and conversion of electrical to mechanical energy. Inverter are used in Current Control device

Dc Brushless Motor Advantages:

1. less rotor heat is generated with the DC brushless drive. Rotor cooling is easier and peak point efficiency is generally higher for this drive.
2. The DC brushless drive can also operate at unity power factor.

Dc Brushless Motor Dis Advantages:

1. brushless DC motor produces no starting torque when directly connected to fixed frequency utility power.
2. Need Inverter and maintained in step with the angular position of the rotor.
3. DC brushless drives require an absolute position sensor

Three-phase Induction Motor function:

Inveted by Nikola Tesla, Three set of Distributed Winding have Used is Stator Core.
Rotor have Different compared into Dc Brushless Motor.
There no magnets are used in Rotor – just stacked steel laminations with buried peripheral conductors that form a “shorted structure.”
Currents flowing in the stator windings produce a rotating magnetic field that enters the rotor and the frequency of this magnetic field is equal to the
difference between the applied electrical frequency and the rotational “frequency” of the rotor, induced voltage exists across the shorted structure
that is proportionate to this speed difference between the rotor and electrical frequency In response to this voltage, currents are produced within the rotor conductors
that are approximately proportionate to the voltage, hence the speed difference and Produce the force.

Three-phase Induction Motor Advantages:

1. 3-phase induction motor is connected to utility type 3-phase power
2. ability to start under load
3. No inverter is needed
4. Add an inverter (without any feedback control) and it becomes possible to power an induction machine from a battery or other DC source.
5. variable speed also becomes possible simply by adjusting the inverter frequency.
6. Induction drives require only a speed sensor
7. Achieving stability over the entire torque-speed range

Three-phase Induction Motor dis-Advantages:

1. Three phase induction motor operate from DC and AC is a must.
2. Shaft speed is proportionate to line frequency.
3. when operated from utility power, they have limited starting torque and somewhat limited running peak torque capabilities
4. Torque performance is low compared with DC machines
5. induction motor best power is 85 percent.
6. Induction machines are more difficult to control.
7. Temperature is more difficult with induction