Final Project: Design of an Electric Vehicle

Electric Vehicle using a DC motor

Using MATLAB Simulink, we have designed an EV having the following configuration:

The MATLAB model developed was as follows:

The various blocks used for this model are as follows-

1. Drive Cycle Source:

The driving reference was simulated by using the FTP75 Drive cycle which is as below-

2. Longitudinal Driver:

The drive cycle is followed using the longitudinal driver that compares a reference and feedback signal and then gives acceleration or deceleration commands.

3. Motor Controller Subsysytem:

This subsystem has the following block configuration-

Controlled PWM Voltage:

This block is used to generate the required duty cycle using the pulse width modulation. The following settings were made-

H-Bridge:

The H bridge block is used to generate 4 quadrant operation as well as chopper operation for the control of motor. It had the following settings-

4. DC motor:

A simple PMDC motor block was used along with the following properties-

5. Battery:

The battery powered EV car was added with a simple battery of 300V.

6. Transmission Subsystem-

This subsystem had the following parts-

Tires:

The tires had the following parameters-

Four such tires were arranged on two axles. The vehicle was designed to be rear driven.

Vehicle Body-

The wind velocity and slope were given as zero.

Simple gear-

Results:

The following model was simulated for 2474 sec which was the length of the drive cycle and the following results were generated:

Speed (m/sec) vs Time (sec)

Distance travelled(km) vs Time (sec)

Inference:

From the results we can infer that the Motor and battery capacity are enough to meet the acceleration demand but due to vehicle inertia it doesn't decelerate to zero everytime. Nevertheless, it follows the drive cycle pattern quite well.

The distance travelled by the EV was 5.3kms and the top speed achieved was around 25m/s.