1. Design of Powertrain for an Electric Car
ED5160 Fundamentals of Automotive Systems
Design of Powertrain for an Electric Car

2. Objective Vehicle specifications of an electric car are given.
Performance requirements are specified.
Determine the specifications of the powertrain to satisfy these requirements.

3. Task 1: Sizing of Transmission Ratio and Motor
This task is to be done by hand calculations.
Consider the acceleration and maximum speed specifications.
The following need to be determined from these performance requirements:
Transmission ratio (GR)

4. Limiting performance criterion
Max speed
Acceleration performance
Rated motor torque
Rated motor power

5. Task 2: Sizing of Battery
This task is to be done using a spreadsheet or code.
Consider the range specification.
The following need to be determined from this performance requirement:
Energy consumption from the battery (per unit distance covered)
Battery energy rating
These quantities depend on the driving cycle.

6. Drive cycle - It is a velocity vs time profile
Drive cycle - It is a velocity vs time profile. Standards specify different drive cycles for different categories of vehicles. For example, the vehicle under consideration is an M1 category vehicle.
Procedure for the task: Divide the drive cycle into 4 phases: idling, cruising, acceleration and braking and develop equations to estimate energy consumed in each phase.

7. Task 3: Bonus
Implement the sizing of the transmission and motor using a spreadsheet or code.
Consider regenerative braking as a factor for the energy sizing of the battery. For the same energy rating, what will be the additional range that can be achieved by the vehicle?