Project-1: Modelling an electric Car with Li-ion battery

Objective: To model (a) an electric car using Lithium ion battery and suitable motor

(b) Vehicle speed control using PI controller to generate the accelerator commands

Description: The complete block diagram for the electric car is shown below:

The input to the system is given by the FTP75 drive cycle source

This gives the reference input to the driver block

The driver block compares the reference input with the actual vehicle speed and gives it to the PID controller. The controller tunes the signal and is given to the satuation block to limit the speed with 100km/hr. The accerleration and deceleration commands are send to the motor controller. The PID is tuned using the Linear Analysis Block.

The output of the driver block is given to the H-bridge motor drive which is driven by the controlled PWM voltage block.

The Litium ion battery is connected via the motor drive.

The drive is connected to the Permanent magnet DC motor

The DC motor is connected to the vehicle body via a simple gear system. The output of the vehicle body is the vehicle speed.

The speed of the vehicle is used to find the distance travelled by the vehicle via the integrator block and dividing it with 3600.

Output and discussion:

The SoC of the vehicle is given below. The vehicle discharges during the acceleration and stops discharging whenever the acceration is zero.

The vehicle speed vs the speed reference is shown below for FTP74 drive cycle source. The vehicle speed matches the speed reference during the entire drive cycle.