Hybrid Drives Development for Conventional Vehicle Model

Theory:-

In a conventional vehicle the power is generated by an internal combustion engine that converts the chemical energy in the fuel to mechanical energy.

This mechanical energy reach the wheels through a drive teain which contains the transmission & differential components.

The efficiency of an IC Engine is defined as the ratio of workdone to the energy supplied to an engine.

The Different types of Efficiencies are:-

• Mechanical Efficiency: It is the ratio of brake power to indicated power.
• Overall Efficiency: It is the ratio of the work obtained at the crankshaft in a given time to the energy supplied by the fuel during same time.
• Indicated Thermal Efficiency: It is the ratio of the heat equivalent to one kw hour to the heat in the fuel per I.P. hour.
• Brake Thermal Efficiency: It is the ratio of the heat equivalent to one kw hour to the heat in the fuel per B.P. hour.
• Volumetric Efficiency: It is the ratio of the actual volume of charge admitted during the suction stroke at N.T.P to the swept volume of the piston.

Model:-

A matlab code "Project1_Intifile.m" was created to load the variable to the workspace. In this project, a typical mid size car with a 1.9L engine & 4 speed automatic transmission is considered.

Data is taken from Advisor data base developed by NREL, USA.

Transmission shift map and controller is taken from Matlab/Simulink example database.

Code:-

%Hybrid Drives Development for Conventional Vehicle Model

%Initialization File for loading the variables

%Vehicle Parameters

M = 1500;

Cr = 0.015;

Rw = 0.35;

Cd = 0.33;

Af = 2;

rhoa = 1.225;

Vwind = 0;

g =9.81;

theta = 0;

myu_road_tyre = 1;

%Powertrain Parameters

FDR = 3.73;

DiffEff = 0.999;

NumGear = 4;

TransGear = [1:NumGear];

TransRatio = [3.06, 1.62, 1, 0.7];

TransEff = 0.90;

TC_SR = [0, .5, .6, .7, .8, .87, .92, .94, .96, .97, 1];

TC_TR = [2.232, 1.5462, 1.4058, 1.2746, 1.1528, 1.0732, 1.0192, 1, 1, 1, 1];

TC_Cf = 1e-4*[.72558, .66322, .63463, .59042, .51331, .4144, .29287, .22444, .12186, .04386, 0];

load Vehicle_data/Engine_data_1.9L_saturn_95kW

load Vehicle_data/Trans_shift_map

%Driver Parameters

Kp = 10;

Ki = 1;

Drive_cycle_select = 2;

%Drive cycle values in m/s

if Drive_cycle_select == 1

load DriveCycles/UDDS;

elseif Drive_cycle_select == 2

load DriveCycles/HWFET;

elseif Drive_cycle_select == 3

load DriveCycles/FTP;

elseif Drive_cycle_select == 4

load DriveCycles/US06;

elseif Drive_cycle_select == 5

load DriveCycles/NEDC;

elseif Drive_cycle_select == 6

load DriveCycles/WLTP;

end

time_end = cyc_time(end);

vel_end = cyc_vel(end);