Project 1

Battery: The battery provides electricity to start the engine and power vehicle electronics/accessories.

Electronic control module (ECM): The ECM controls the fuel mixture, ignition timing, and emissions system; monitors the operation of the vehicle; safeguards the engine from abuse; and detects and troubleshoots problems.

Exhaust system: The exhaust system channels the exhaust gases from the engine out through the tailpipe. A three-way catalyst is designed to reduce engine-out emissions within the exhaust system.

Fuel filler: A nozzle from a fuel dispenser attaches to the receptacle on the vehicle to fill the tank.

Fuel injection system: This system introduces fuel into the engine's combustion chambers for ignition.

Fuel line: A metal tube or flexible hose (or a combination of these) transfers fuel from the tank to the engine's fuel injection system.

Fuel pump: A pump that transfers fuel from the tank to the engine's fuel injection system via the fuel line.

Fuel tank (gasoline): This tank stores gasoline on board the vehicle until it's needed by the engine.

Internal combustion engine (spark-ignited): In this configuration, fuel is injected into either the intake manifold or the combustion chamber, where it is combined with air, and the air/fuel mixture is ignited by the spark from a spark plug.

Transmission: The transmission transfers mechanical power from the engine and/or electric traction motor to drive the wheels.

FORWORD MODEL

forword model is somthing like forword engineering is a method of creating or making an application with the help of the given requirements and the output is given is the input as in the form of feedback. which let us know how much difference is there in between actual and desired values.

A drive cycle is typically represented by a series of data points which plots vehicle speed against time. Driving cycles are produced to assess the performance of vehicles in various ways, including fuel consumption and pollutant emissions.different drive cycles like UDDS, HWFET, FTP, NEDC, etc.

here we are running the code to load the values and variable so that we can use this values in simulink model.this script defines the inputr values of that are required for the calculation .

if else loop is used so that when we change the drive cycle selection values between (1-6) the datata of that drive cycle will be loaded.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Skill-Lync -> Hybrid Drives Development
% Project 1 - Conventional Vehicle Model
% By - RITIK SONKAMBLE
clear all
close all
clc
% Description:

%% Initialization File
% Initialization file for loading the variables for the Conventional vehicle simulation model

%% Vehicle Parameters
M = 1500;       % Vehicle weight [kg]
Cr = 0.015;     % Rolling resistance coefficient
Rw = 0.35;      % Rolling radius [m]
Cd = 0.33;      % Drag coefficient
Af = 2;         % Frontal area [m2]
rhoa = 1.225;   % Air density [kg/m3]
Vwind = 0;      % Wind velocity [kmph]
g = 9.81;       % Gravitational acceleration [m/s2]
theta = 0;      % Slope [deg]
myu_road_tire = 1; % Coefficient of friction between tire - road interface

%% Powertrain Parameters 
FDR = 3.73;                         % Final Drive Ratio / Diff Ratio
DiffEff = 0.99;                     % Differential efficiency (assumed independent of operating conditions)

NumGear = 4;                        % Number of gears in transmission
TransGear = [1:NumGear];            % Transmission Gears
TransRatio = [3.06, 1.62, 1, 0.7];  % Corresponding Transmission ratios
TransEff = 0.90;                    % Transmission efficiency (assumed independent of operating conditions)

TC_SR = [0, .5, .6, .7, .8, .87, .92, .94, .96, .97, 1];   % Torque Converter Speed Ratio (Matlab default) -> TurbSpd/PumpSpd  
TC_TR = [2.232, 1.5462, 1.4058, 1.2746, 1.1528, 1.0732, 1.0192, 1, 1, 1, 1];   % Torque Converter Torque Ratio (Matlab default) -> TurbTrq/PumpTrq
TC_Cf = 1e-4 * [.72558, .66322, .63463, .59042, .51331, .4144, .29287, .22444, .12186, .04386, 0]; % Torque Converter Capacity Factor (Matlab default) -> PumpTrq/PumpSpd^2 [Nm/rpm^2]

load Vehicle_Data/Engine_data_1_9L_Saturn_95kW
load Vehicle_Data/Trans_Shift_map

%% Driver Parameters
Kp = 10;                    % P gain for driver PI model
Ki = 1;                     % I gain for driver PI model
Drive_Cycle_Select = 1   % Drive cycle selection

% Drive cycle values in m/s

if Drive_Cycle_Select == 1
    load DriveCycles/UDDS;
    fprintf('UDDS CYCLE IS LOADED \n')
    
elseif Drive_Cycle_Select == 2
    load DriveCycles/HWFET;
     fprintf('HWFET CYCLE IS LOADED \n')

elseif Drive_Cycle_Select == 3
    load DriveCycles/FTP;
     fprintf('FTP CYCLE IS LOADED \n')

elseif Drive_Cycle_Select == 4
    load DriveCycles/US06;
     fprintf('US06 CYCLE IS LOADED \n')
    
elseif Drive_Cycle_Select == 5
    load DriveCycles/NEDC;
     fprintf('NEDC CYCLE IS LOADED \n')
    
elseif Drive_Cycle_Select == 6
    load DriveCycles/WLTP;
     fprintf('WLTP CYCLE IS LOADED \n')
 
end

time_end = cyc_time(end);
vel_end = cyc_vel(end);

end of the script in command window shows the drive cycle 1 that mean the values of that drive cycle is loaded.

this model consist of 3 main sub system

‘Driver’ block, which is a basic PI controller that generates accelerator and brake pedal outputs to match the desired and actual vehicle speeds.

‘Controller’ block is the brains of the vehicle, representing the electronic controls units. Based on the driver inputs, it generates desired engine torque, desired transmission gear and desired brake torque. These inputs are fed to the ‘Powertrain’

‘Powertrain’ block which represents the drivetrain of the vehicle. It consists of an ‘Engine’ connected to the ‘Automatic Transmission’ through a ‘Torque Converter’. The output of the transmission is connected to the ’Differential’, which powers the ‘Wheels’, that provides the tractive force for vehicle acceleration. The longitudinal dynamics of the vehicle along with the road load is represented in the ‘Vehicle Dynamics’ block. whig finally gives the velocity this velocity if given back to the driver block as feed back and ckeck the difference between actual vs desired vehical speed.

driver block works on a PI controller PI controller takes the error and integrates it with a constant and gives the output. Here we have drive cycle (desired) and velocity (actual) which is vehical speed for calculating an error. For drive cycle we are providing time as input. the output of the PI controller is divided into 2 parts and saturated as possitive value for acceleration AND negative vaues for brake negative gain block is used to convert the negative sign of the brake as positive.

this graph compaires the desired and actual velocity.

CONTROLLER BLOCK

controller block takes acceleration and brake as input and provide ENGINE TORQUE ,GEAR , BREAK TORQUE AS OUTPUT this output is given to bus controller to get all in 1 single output .

controller block works on 3 main sub system

ideal controller is given so that it does not exceed the ideal speed. this is added to the throttle that is recieved from the driver and based on maximum and minimum torque curve we calculare the enginr torque required.

idle speed controller is consist of PI controller where is thkes the error of engine ideal speed values (constant) and engine speed value and then calculate the throttle idle by saturating possitive value from 0 to 100.

Transmission Control Unit works on state folow chart where the input are given as throttle and velocity and gives output as gear combination velocity is converted into m/s to mph. by using a gain block.

this is how gear system logic looks like,

gear state consist of 4 gear which changes upon up and down condition. this condition are computed from another selection state which works on the simulink function.

the product of brake and max friction depended on tire to road interface and weight of the vehical is calculated for break trqe .

this is the final output of what engine torque is required ,what gear will be selected and what is the brake torque is required.

this block is designed to calculate the fuel consumption in the engine at specific fuel rate on the basis of torque required.the torque required is checked whether the torque is between max or min torque curve and then pass it to the fuel consumption map.based on the speed and torque fuel consumption is calculated and provide the fuel consumption in gram/sec. we are using to work space block to sent the values to the main workspace so that we can use those values for plotting.saturation block is used to filter the values between the given limit which is 0.5 to -0.5.integrator is used to convert fuel rate into fuel consumption.

TRANSMISSION

this block takes engine torque and gear selector and provide torque output.onthe basis of gear selector by the driver the gear ratio is filtered from the look up table.

torque convvertor is used to convert it into transmission torque which is multiplyed by the gear ratio and gives to the switch which on the bases of effency and as (possitive) and loss (negative) provide the output transmission torque.

scope output of transmission system.

we are useing torque converter as a fluid coupling device because this system is consist as an automatic transmission torque converteris used. main purpouse is to connect the engine to the transmission.

figure shows the output pump and turbine torque analysis.

here we are providing transmission output torque to th differential ratio which gets multiplyed and gives the possitive and negative values (effiency and losss).and passes to the switch which according to the condition gives the axle torque.we are using to work space block to sent the values to the main workspace so that we can use those values for plotting.

wheel recieve axile torque and subtract break torque from it and we wll get net wheel torque which is divided buy rolling radius to give tractive force. we are assuming as no loss of traction for simple calculation.

this block is used to calculate the acceleration of the vehical which is integrated to find velocity which is integrated to get the distance.where the input is given as tractive force subtracted by the sum of drag resistance, grading resistance ,rolling resistance.

this shows various forces acting in graph.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Skill-Lync -> Hybrid Drives Development
% Project 1 - Conventional Vehicle Model
% By - RITIK SONKAMBLE


%% Post-Processing File
%  File for post-processing the Conventional vehicle simulation model data

%% Renaming variables
Time = out.tout;
Acc_Pdl = out.Acc_Pdl;          % Accelerator pedal [%]
Brk_Pdl = out.Brk_Pdl;          % Brake pedal [%]
Gear_Cmd = out.Gear_Cmd;        % Transmission gear
Trans_In_Spd = out.Trans_In_Spd*30/pi;  % Transmission input speed [rpm]
Trans_Out_Spd = out.Trans_Out_Spd*30/pi;% Transmission output speed [rpm]
Eng_Trq = out.Eng_Trq;          % Engine brake torque [Nm]
Eng_Spd = out.Eng_Spd*30/pi;    % Engine speed [rpm]
Eng_Fuel_Consump = out.Eng_Fuel_Consumption;    % Engine fuel consumption [g]
Veh_Dist = out.Veh_Dist/1000;   % Distance traveled by vehicle [km]
Veh_Spd = out.Veh_Spd*18/5;     % Vehicle speed [kmph]
WheelSpd=out.WheelSpd;            % wheel speed [rpm]
Eng_Fuel_rate=out.Eng_Fuel_Rate;
%% Data Analysis
Eng_Pwr = Eng_Spd.*pi./30.*Eng_Trq./1000;   % Engine brake power [kW]
rho_petrol = 0.7197;                    % Density of petrol [kg/L]
kmpl = Veh_Dist(end)/(Eng_Fuel_Consump(end)/1000/rho_petrol);    % Fuel economy [kmpl] 

%% TIME TRACT FOR ENGINE
figure(1)
hold on
grid on
plot(Time,Trans_In_Spd, 'linewidth', 1, 'Color', 'black')
plot(Time,Trans_Out_Spd, 'linewidth', 1, 'Color', 'red')
plot(Time,WheelSpd, 'linewidth', 1, 'Color', 'green')
xlabel('time [s]')
ylabel('speed [rpm]')
xlim([0, Time(end)]);
ylim([0, 6000]);
legend('Trans In Spd','Trans Out Spd','WheelSpd')
%% Plotting torque ,power,fuel rate,fuel consumption
figure(2)
subplot(4,1,1)
grid on
plot(Time, Eng_Trq, 'linewidth', 1, 'Color', 'black');
xlabel('time [s]')
ylabel('engine torque [Nm]')
xlim([0, Time(end)]);
subplot(4,1,2)
grid on
plot(Time, Eng_Pwr, 'linewidth', 1, 'Color', 'blue');
xlabel('time [s]')
ylabel('engine power [Nm]')
xlim([0, Time(end)]);
subplot(4,1,3)
grid on
plot(Time,Eng_Fuel_rate, 'linewidth', 1, 'Color', 'green');
xlim([0, Time(end)]);
xlabel('Time [s]');
ylabel('engine fuel rate');
subplot(4,1,4)
grid on
plot(Time,Eng_Fuel_Consump, 'linewidth', 1, 'Color', 'red');
xlim([0, Time(end)]);
xlabel('Time [s]');
ylabel('engine fuel consumption');
%% Plotting vehicle characteristics time trace
figure(3)
subplot(4,1,1)
hold on
grid on
plot(Time, Acc_Pdl, 'linewidth', 1, 'Color', 'black');
plot(Time, Brk_Pdl, 'linewidth', 1, 'Color', 'red');
ylabel('Pedal [%]')
xlim([0, Time(end)]);
legend('Accel','Brake');
subplot(4,1,2)
hold on
grid on
plot(Time, Gear_Cmd, 'linewidth', 1, 'Color', 'black');
xlim([0, Time(end)]);
xlabel('Time [s]');
ylabel('Gear');
subplot(4,1,3)
hold on
grid on
plot(cyc_time,(cyc_vel.*(18./5)), 'linewidth', 1, 'Color', 'black');
plot(Time, Veh_Spd, 'linewidth', 1, 'Color', 'red');
ylabel('velocity')
xlabel('Time [s]');
xlim([0, Time(end)]);
legend('desired speed','Actual speed');
subplot(4,1,4)
hold on
grid on
plot(Time, Veh_Dist, 'linewidth', 1, 'Color', 'black');
xlim([0, Time(end)]);
xlabel('Time [s]');
ylabel('distance [km]');

%% Plotting engine operating points on engine fuel map
figure('Name','Engine Operating Points');
hold on
grid on
title('Engine Operating Points','fontsize',12);
p1=plot(Eng_map_spd*30/pi,Eng_max_trq,'linewidth',2,'color','r');
p2=line([Eng_map_spd(end)*30/pi Eng_map_spd(end)*30/pi],[0 Eng_max_trq(end)]);
set(p2,'linewidth',1,'linestyle','--','color','k');
p3=line([Eng_map_spd(1)*30/pi Eng_map_spd(1)*30/pi],[0 Eng_max_trq(1)]);
set(p3,'linewidth',1,'linestyle','--','color','k');
[c,h] = contour(Eng_map_spd'*30/pi,Eng_map_trq,Eng_fuel_map');
clabel(c,h);
xlabel('Engine Speed [rpm]');
ylabel('Engine Torque [Nm]');
title('Engine Fuel Consumption Map [g/s]');
p4 = plot(Eng_Spd,Eng_Trq,'.','color','k');
legend([p1 p4],{'Max Curve','Operating Points'});
axis([Eng_map_spd(1)*30/pi Eng_map_spd(end)*30/pi 0 Eng_map_trq(end)]);

in this code we will plotthe values that are extracted from the simulink model and compair it with {UDDS CYCLE VS HWFET CYCLE}

WE WILL SEE PLOT FOR

1. Tabulate the fuel economy numbers (kmpl) for UDDS and HWFET cycle.
2. Plot the time trace for engine, transmission input, transmission output and wheel speed on one plot.
3. Plot engine torque, engine power, fuel rate and fuel consumption using subplots.
4. Plot accelerator and brake pedal, gear command, vehicle desired and actual speed,vehicle distance using subplots.
5. Plot the engine operating points on the engine fuel map.

1. Tabulate the fuel economy numbers (kmpl) for UDDS and HWFET cycle.

fuel economy numbers (kmpl) for UDDS cycle = 16.8534

fuel economy numbers (kmpl) for HWFET cycle = 21.2041

fuel economic number is in HWFET cycly is higher because ther is low pealing which cause low energy loss which cause less fuel consumption where as as compaire to UDDS cycle there is more pedeling means more energy loss due to loss which cause more fuel consumption .

2. Plot the time trace for engine, transmission input, transmission output and wheel speed on one plot.

in the below figure1 we there is more fluctuation in speed .means transmisson speed is decreasing to zero in every few time which cause less out energy generation .as compaire to figure 2 we can see that there is less fluctuation means transmission speed is very low to zero for long period of time which produce more energy. we can see this in figure no 5 AND 6 FIRST PLOT.

FIGURE 1 : engine, transmission input, transmission output and wheel speed FOR UDDS CYCLE

FIGURE 2 : engine, transmission input, transmission output and wheel speed FOR HWFET CYCLE.

3 . Plot engine torque, engine power, fuel rate and fuel consumption using subplots.

in figure 3 and 4 we can see the engine torque, engine power, fuel rate is directly proportional to each other . which means as engine power is increased the torque is also increased and at time fuel rate is also increase the main difference between figure 3 and 4 is fluctuation due to instant increase and decrease in power,torque ,fuel rate. due to the driving condition.

FIGURE 3: engine torque, engine power, fuel rate and fuel consumption FOR UDDS CYCLE

FIGURE 4: engine torque, engine power, fuel rate and fuel consumption FOR HWFET CYCLE

4. Plot accelerator and brake pedal, gear command, vehicle desired and actual speed,vehicle distance using subplots.

in figure 5 we can see that if the gear is not constant for long period we will recieve less velocity where as in figure 6 the gear is constant for long period means velocity is also increasing due to which there is less pedeling and cause less power loss. by looking at the graph 5 and 6 we can identify that vehical is stopped multipal time in a given distance due to zero velocity at multipal time for UDDS cycle where as in HWFET cycle no vehical stop multipal time in given diastance due to gradually increasing and decreasing in velocity without making it zero.

FIGURE 5: accelerator and brake pedal, gear command, vehicle desired and actual speed,vehicle distance for UDDS CYCLE

FIGURE 6: accelerator and brake pedal, gear command, vehicle desired and actual speed,vehicle distance for HWFET CYCLE.

5. Plot the engine operating points on the engine fuel map.

from the below figures we can see that in UDDS CYCLE engine operating point are exceding the max curve wher as in HWFET CYCLE the engine operating points are low. in both the figure we can see that there is much nigher RPM is availabe which is not used 60000.

FIGURE 7: Engine operating points FOR UDDS CYCLE

FIGURE 8: Engine operating points FOR HWFET CYCLE

link to access :

https://drive.google.com/drive/folders/1ZArTjjUGOk4YBlhz09DL-IuPuLY7SyXn?usp=sharing

CONCLUSION:

hence i we have tudied how Conventional Vehicle Model is designed and work by using matlab coding and and matlab simulink.

we had studyed how the graph of the vehical is plotted with different drive cycle .

THANK YOU