Project 2

1. The ‘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’ block which represents the drivetrain of the vehicle.
2. a state flow machine is used to represent the supervisory control unit which decided the operating mode while its is start /stop mode or cruising mode or regen braking mode for each modes the engine drive and the motorr drive are controlled.

1. the input to the state flow charts is accle. and brake pedal input from the driver unit engine actual speed actual vehicle speed soc status ant the clutch lockup stste and the output to the controller are the mode engine on /off request engine input thottle and electric motor input throttle.
2. all control signal passed to transmission model which represent the drive train.

Engine control unit:

1. engine control unit compare engine speed with the maximum torque and minimum torque curve of the lookup table and give the required torque command to the engine block. the throttle input is combine with the idle speed throttle and gains with torque output from the lookup table to estimate the torque input required for the engine.
2. throttle input idle throttle and their sum can be scoped from this block.

Idle speed controller;

Transmission control block;

The transmission control block control the gear shifting using the study flow variable chart.

The gear shifting is controlled according to the vehicle speed and throttle input.

The gear command is passed to the transmission block to select the desired gear ratio.

Electric motor control unit;

Motor control unit compare EM speed with the max torque curve and max torque generation curve of the lookup table and give the required torque command to the electric motor the EM throtle input is used to compare the lookup table and to estimate the torque input required for the e-motor.

Brake control unit;

Brake control unit produce required brake torque according to the brake pedal input and passes the brake torque in to the wheel block in the transmission model.

Powertrain model;

The power train model include all the components that converts the power of the engine into the vehicle motion.
This includes the engine,e-motor,battery pack,transmission,diffential,wheels,and vehicle body dynamics subsystem.

Battery model;

A battery pack subsystem is created with electric power input and battery soc as output
2 diff. subblock have been created to determine the soc and termonal voltage seperately soc is used to determine he terminal voltage.

SOC Estimation model;

pack current in ampere is converted to amphr and divides with max capacity and adds with the initial soc to determine the soc of the battery at each instance the soc value is limited betwen 0 to 1.

Terminal voltage model;

Ideal voltage and internal resistance are determined by 1D lookup table and battery voltage is determoned using the model.
The specified values are send back to workspace using the to workspace block and can be used for post processing.

Engine model;

1. Based on the engine speed the required torque from the controller is saturated between max torque curve and min torque curve and passes the engine torque to the transmission block
   
2. The 2D lookup table is used to calculate the fuel flow rate based on engine speed and engine torque.
   
3. The new engine also has an on/off feature to eliminate the fuel flow rate when the engine is off also the engine torque cannot be negative torque as min.torque curve mode saturated.
   
4. The fuel rate is then integrated to find the fuel consumption.
   
5. Estimated fuel flow rate fuel consumption engine torque and engine speed are passed to the MATLAB workspace using the to-workspace block
   
6. Engine fuel flow rate and fuel consumption are scoped.

Electric Motor Model;

Based on the engine speed the required EM torque from the cotroller is saturated between max EM torque curve and max EM torque generation curve and passes the EM torque to the crank hub
the 2D lookup table is used to calculate the input electric power to the motor basd on the EM speed and EM torque.

crank hub;

Crank hub adds up the EM torque and the engine torque and pass it to the transmission block as the crank torque.

Transmission model;

The engine block is connected to the automatic transmission via a torque converter the output of the transmission is connected to the differential.

Torque converter;

The gear selection from the transmission control unit is multiplied by the engine torque in this block and the efficiency and engine dynamics of the torque converter are applied in this model.

Differential Model;

The transmission output torque is multiplied by the differential ratio and differential effieciency in this block and the torque is transmiteed to the wheel as the axle torque.

Wheel Model;

The brake torque from the control model is subtracted from the axle torque and divides from the rolling radius to determine the tractive force
The wheel speed is calculated from the vehicle velocity and saved in the workspace.

Vehicle dynamics;

The longitudinal dynamics of the vehicle along with the road load is represented in the vehicle dynamics block
Tractive force and road loads are used to calculate the vehicle velocity

1. Tractive force = ηt*λt*Te/Rw = M*(dVveh/dt) + 0.5 *ρa *Af*Cd*(Vveh+Vwd)^2 + Cr*M*g*cosθ +M*g*sinθ

2. Road load = 0.5 *ρa *Af*Cd*(Vveh+Vwd)^2 + Cr*M*g*cosθ +M*g*sinθ

where,

ρa = air density

Af = frontal area

Cd = drag co-efficients

Cr = rolling co-efficients

M = vehicle mass

g = acceleration due to gravity

θ = slope

1. The variable are loaded on the workspace using MATLAB scripts.
2. The acceleration velocity and distance travelled are calculated and stored in the workspace.

Post processing file;

%% Hybrid Drives Development

% Project 2 - P1 Hybrid Vehicle Model

% By - Mohammed Asad Ali

%% Post-Processing File

% File for post-processing the P1 Hybrid 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]

Eng_Fuel_Rate = out.Eng_Fuel_Rate; %engine fuel rate

Veh_Dist = out.Veh_Dist/1000; % Distance traveled by vehicle [km]

Veh_Spd = out.Veh_Spd*18/5; % Vehicle speed [kmph]

Whl_Spd = out.Whl_Spd*30/pi; % wheel speed[RPM]

Desired_spd = out.Desired_Velo*18/5 ; %desired speed [KMPH]

EM_Spd = out.EM_Spd*30/pi; % E motor speed[rpm]

EM_Trq = out.EM_Trq; % E motor torque[Nm]

EM_Pwr = out.EM_Pwr; % E motor input power[W]

V_batt = out.V_battery; % battery pack voltage [V]

I_batt = out.I_battery; % battery pack current [I]

SOC = out.SOC; % STATE OF CHARGE [%]

RS = out.RS; % internal resistance

VOC = out.VOC; % open circuit voltage

%% 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];

% display fuel Economy of the cycle

formatspec = 'fuel economy is %2.2f kmpl';

fprintf(formatspec,kmpl);

%% Plotting vehicle characteristics time trace

% ploting transmission input,transmission output and wheel speed

figure(1)

hold on

grid on

plot(Time,Trans_In_Spd);

plot(Time,Trans_Out_Spd);

plot(Time,Veh_Spd);

xlabel('Time[s]')

ylabel('speed[rpm]')

xlim([0,Time(end)]);

legend('trans input','trans Output','wheel speed');

title('transmission input transmission output and wheel speed')

% plotting engine torque,engine power,fuel rate ,fuel consumption

figure(2)

subplot(4,1,1)

hold on

grid on

plot(Time,Eng_Trq,'LineWidth',1,'Color','black');

ylabel('torque[NM]')

xlim([0,Time(end)]);

title('Engine Torque')

subplot(4,1,2)

hold on

grid on

plot(Time,Eng_Pwr,'LineWidth',1,'Color','black');

ylabel('power[KW]')

xlim([0,Time(end)]);

title('Engine Power')

subplot(4,1,3)

hold on

grid on

plot(Time,Eng_Fuel_Rate,'LineWidth',1,'Color','black');

xlim([0,Time(end)]);

xlabel('Time[s]');

ylabel('Engine fuel rate');

title('Engine fuel rate')

subplot(4,1,4)

hold on

grid on

plot(Time,Eng_Fuel_Consump,'LineWidth',1,'Color','black');

xlim([0,Time(end)]);

xlabel('Time[s]');

ylabel('Engine fuel consumption[g]');

title('Engine Fuel Consumption')

% plotting accelerator and brake pedal gear command vehicle desired and actual speed ,vehicle distance

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');

title('Acceleration and brake pedal inputs')

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');

title('gear command')

subplot(4,1,3)

hold on

grid on

plot(Time, Veh_Spd, 'linewidth', 1, 'Color', 'black');

ylabel('Speed [kmph]')

xlim([0, Time(end)]);

legend('actual speed','desired speed');

title('vehicle actual and desired 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]');

title('vehicle distance')

% plotting drive cycle

figure(4)

hold on

grid on

plot(cyc_time,cyc_vel,'LineWidth',1,'Color','black')

xlabel('time[s]')

ylabel('velocity[mph]')

title('drive cycle')

% test result

Avg_speed = sum(Veh_Spd)/length(Veh_Spd);

Max_speed = maxk(Veh_Spd,1);

table (Avg_speed,Max_speed,kmpl,'variablenames',{'average speed[kmph]','maximum speed[kmph]','fuel economy[kmpl]'})

%% Plotting engine operating points on engine fuel map

figure('Name','Engine Operating Points');

hold on

grid on

title('Engine Operating Points','fontsize',12);

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]');

legend({'Max Curve','Operating Points'});

axis([Eng_map_spd(1)*30/pi Eng_map_spd(end)*30/pi 0 Eng_map_trq(end)]);

%% Electric Motor

% plotting motor speed ,motor torque,motor input power

%% BATTERY

% plotting pack current,voltage,soc,internal resistance,open circuit

% voltage

figure(7)

subplot(5,1,1)

plot(Time,V_batt,'LineWidth',1,'Color','r');

xlabel('Time[sec]');

ylabel('voltage[v]');

title('pack voltage')

xlim([0,Time(end)]);

grid on

subplot(5,1,2)

plot(Time,I_batt,'LineWidth',1,'Color','b');

xlabel('Time[sec]');

ylabel('current[I]');

title('battery current')

xlim([0,Time(end)]);

grid on

subplot(5,1,3)

plot(Time,SOC,'LineWidth',1,'Color','g');

xlabel('Time[sec]');

ylabel('SOC[%]');

title('STATE OF CHARGE')

xlim([0,Time(end)]);

grid on

subplot(5,1,4)

plot(Time,RS,'LineWidth',1,'Color','r');

xlabel('Time[sec]');

ylabel('Internal resistance[ohm]');

title('Internal resistance')

xlim([0,Time(end)]);

grid on

subplot(5,1,5)

plot(Time,VOC,'LineWidth',1,'Color','b');

xlabel('Time[sec]');

ylabel('Open circuit voltage[v]');

title('Open circuit voltage')

xlim([0,Time(end)]);

grid on

%% Plotting engine operating points on engine fuel map

figure('Name','Electric motor Operating Points');

hold on

grid on

title('Electric motor Operating Points','fontsize',12);

p1=plot(EM_map_spd*30/pi,EM_max_trq,'linewidth',2,'color','r');

p4=plot(EM_map_spd*30/pi,EM_max_gen_trq,'LineWidth',2,'Color','b');

p2=line([EM_map_spd(end)*30/pi EM_map_spd(end)*30/pi],[EM_max_gen_trq(end) EM_max_trq(end)]);

set(p2,'linewidth',1,'linestyle','--','color','k');

p3=line([EM_map_spd(1)*30/pi EM_map_spd(1)*30/pi],[EM_max_gen_trq(1) EM_max_gen_trq(1)]);

set(p3,'linewidth',1,'linestyle','--','color','k');

[c,h] = contour(EM_map_spd'*30/pi,EM_map_trq,EM_inpwr_map');

clabel(c,h);

xlabel('Motor Speed [rpm]');

ylabel('motor Torque [Nm]');

title('Motor in power map [W]');

legend([p1 p4 p3],{'Max Curve','regen curve','Operating Points'});

xlim([EM_map_spd(1)*30/pi EM_map_spd(end)*30/pi]);

ylim([EM_max_gen_trq(1) EM_max_trq(1)]);

Post processing Result;

Drive Cycle;

We have 2 cycle

1. UDDS cucle

2. HWFET cycle

1. UDDS.

Drive cycle

2. HWFET cycle.

2. Fuel Economy Numbers (KMPL)

UDDS CYCLE;

2. HWFET cycle.

The time trace for engine ,transmission input,transmission output,wheel speed;

1. UDDS CYCLE;

2. HWFET cycle.

1. Much of the fluctuating input speed is facilitated by the torque convertor and the transmission input speed fluctuates according to the engine torque required to achive the drive cycle.
2. wheel speed and transmision output speed vary according to gear and differential ratio.

Engine torque,engine power,fuel rate,fuel consumption;

1.UDDS CYCLE;

2. HWFET cycle.

Accelerator and brake pedal,gear command,vehicle desired and actual speed,vehicle distance:

1.UDDDS CYCLE;

2. HWFET cycle.

1. Acceleration and brake pedals are used more bcoz the drive cycle is not very smooth and the gear has to be shifted frequently.
2. Brake requirement are lower more acceleretor pedal are applied on the highway drive cycle and gear shift often occurs bcoz the drive cycle is smoother.
3. Acceleration and brake pedal the gear command of the transmission control unit the required speed of the vehicle the actual speed and the actual vehicle distance are plotted.

The engine operating points on the engine fuel map;

1.UDDS CYCLE;

2. HWFET cycle.

1. The engine operating points are plotted on the fuel map and the operating points is under the maximum torque curve.

The motor speed,motor torque,motor input power;

1. UDDS

2. HWFET cycle.

The pack voltage ,current,SOC, VOC,internal resistance;

1.UDDS

2. HWFET cycle.

The motor operating points on the motor inputs power map,with the motor max motoring and generating torque curves;

1. UDDS

2. HWFET cycle.

CONCLUSION ;

1. Therefor the forward energy based fuel consumption model of a P1 Hybrid vehicle has been successfully simulated using MATLAB and SIMULINK.Analysis and understand vehicle operating points based on engine.

2.Speed,torque,transmissionspeed,pedalposition,gear,distance,velocity,acceleration,battery,voltage,current,SOC and pedal position acceleration,battery,voltage,current,SOC and pedal position.

3. Post process calculation were performed and the required graphs were successfully plotted.

Succesfully calculated vehicle fuel efficiency number(kmpl) for the given city cycle UDDS and highway cycle HWFET.and also compared to the conventional vehicle.

Thank you,