Project 2

THE SIMULINK MODEL:

WORKING OF EV-CAR MODEL:

The Drive Cycle Source block generates a FTP75 longitudinal drive cycle and give specified vehicle longitudinal speed.It Produce realistic velocity and shift references for closed loop acceleration and braking commands for vehicle control according to FTP75 drive cycle its value varies from 0 to 1.This acceleration and brake commands are given to simulink to ps converter ,this block converts those signals to physical system signalThis signal is given to physically controlled voltage source.It produces voltage output according to the physical signal input,these output are also varies between zero to 1The output of controlled voltage source1 goes to controlled PWM voltage and output of controlled voltage source goes to brak input of H bridgeIn controlled PWM voltage we set mininum input voltage 0 and maximum input voltage 1 because the input varies between 0 and 1 .It give output according to input signalsThese output values is fed to a H bridge. If the input signal has a value greater than the Enable threshold voltage parameter value 2.5V the H-Bridge block output is on and has a value equal to the value of the Output voltage amplitude 800V. If it has a value less than the Enable threshold voltage parameter value, the block maintains the load circuit using freewheeling diode.The Output of H bridge is connected to dc motor the motor rotates according to the voltage output fom h bridge.The current flowing through H bridge given goes to controlled current source and it controled current in battery circuit and give SOC% accordinglyThe transmission is happening in dc motor here the electrical energy is converting to mechanical energy.The mechanical outputfrom the motor is given to vehical body subsytem ,It first go to a simple gear with tooth ratio 10,So it multiply torque to tentimes and given to the axle ,the inertia block provide proper inertia to tire to move.The resulting traction motion developed by tires is given to vehicle body through port H. Then physical signal output ports NF and NR goes to front and rear tires thses are normal wheel forces, which moves the tires.Headwindspeed and road inclination values are also given The vehicle body gives the Speed output according to the input given to it.

Energy analysis of the EV:

The vehicle parameters taken are:

Vehicle body weight (kg):800kg

width in m:1.8

height in m:1.96

Drag co-efficientL:0.4

Rolling resistance:0.015

DC Motor Rated load (kW):60kw

Rated DC supply voltage (V):300V

The fORCES THAT HAS TO BE CALCULATED FOR ENERGY ANALYSIS ARE:

Rolling Resistance Force= μrr*m*g

=800*9.8*0.015

=117.6N

Frontal Area=0.85*Width*Height=3m^2

Airdrag force=0.5*ρ*A*Cd*V^2 = 0.360*v^2

Hill climbingforce=m*g*sin(Ψ)=110N

Angle of inclination =0.01rad,

Accelerational force=m*a

=800*a

Here total tractive force is calculated using formula,Tractive force=Accelerational force+ Rolling Resistance Force+ Hill climbingforce+Airdrag force This total tractive force vis multiplied with speed to find propulsion power,then a integrator block is given to calculate total tractive energy.

Results:

CASE 1: DRIVE CYCLE FTP75 IS GIVEN AS INPUT