Week-4 Challenge WOT Condition Part-2

Q1

Mapped model

The mapped model is one type where the data points are pre assigned in lookup tables.
The engine or motor torque required is sensed and the motor or engine block generates the requiered torque output just as required simply without considering the real time motor or engine, parameters.
The output values are stored for the corrresponding given input values of the engine motor and generator.
The accuracy of this type is not that high but the simulation will be done in much less time as it does not run by real time parameters.

Dyanamic model

The dyanamic model in other hand uses the combination of the outputs from various subsystems to generate the output.

It runs by real time simulation where the required input from the drive cycle is taken and for that individiual real time simulation gets performed and summing all the results of the subsystem gives the output for the simulation.

As per the drive cycle requirements the initial Bus voltage ,current is given along with the vehicle feedback so that it runs the actual simulation at that particuclar moment throught the drive cycle.

The accuracy of this model is very high as it considers the real outputs from all the subsystem to generate the output.

The simulation will take very long time to complete as it has so many individual simulations running by all the subsystem of the engine , motor/generator.

The figure below shows the working phase of the dyanamic model.

Q2

Milles per gallon

Miles per Gallon is a fuel economy rating determined by how far a car can travel on a gallon of petrol or Diesel for a Engine powered car.

In case of an electric vehicle it tells us the energy which is equivalent that of a engine powered carto propel the car through a distance.

The amount of Fuel Energy required to move a engine powered car through a distance is determined and then it is compared to the eqivalent amount of electric energy required to move the car throgh the same distance and is expressed as the miles per gallon.

The powertrain blockset has a model that calculates the miles per gallon for all kinds of vehicle.

Vehicle Speed And Fuel Flow

The Vehicle speed is a important factor while considering the fuel consumption at that particular time,so to determine the fuel consumption throughout the drive cycle.

To convert speed to Distance we can Integrate with time and we are doing the same of converting the velocity to get distance covered by integrating.

Battery Power

The amount of Energy from battery power required to propel the vehicle Equivalent to that of the Engine is calculated here.

The battery power is given in watts and it is converted to Kw by dividing with 1000.

Then we convert the power into energy by multiplying with the time into KWh.

Q3

Hybrid Electric Vehicle:

A hybrid electric vehicle (HEV) is a type of hybrid type that combines a conventional Internal combustion engine system with an electric propulsion system

The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional vehicle or better performance.

Example of HEV is Toyota Prius.

Case1

Simulation condition:

The simulation is done for Hybrid electric vehicle with Wide open Throttle Drive cycle.The Total cycle time = 100 seconds

The Top speed of this cycle = 80 mph

Time to start deceleration = 50seconds

The Grade angle = 0 degrees

The wind velocity = 0 m/s

plot 1:

Shows the velocity of the vehicle with respect to the Drive cycle data with the Time scale on the x axis.

The acceleration time to reach 80 mph - 16.7 seconds

The deceleration time from 80 to minimum = 6.2 seconds

plot 2:

Shows the changes in speed of the Engine,motor and Generator in Rpm throughout the drive cycle.

Peak Engine speed = 4780 Rpm

Peak Motor speed = 9497 Rpm

Peak Generator speed = 13690 Rpm

plot 3:

Shows the Torque characteristics and its changes of engine,motor and generator in (Nm) throughout the drive cycle.

Peak Engine torque = 138.7 Nm

Peak Motor torque = 206.7 Nm

Peak Generator torque = 42.2 Nm

plot 4:

Shows the Battery Current values (A) and its changes for various acceleration inputs as per the Drive cycle.

The peak current discharge from the battery = 163.5A

The peak current charging to the battery = -150.86 A

Plot 5:

Shows the Battery state of charge SOC (%) and its changes corresponding to the driving inputs.

The state of charge decreased from 60% to 39.8% of charge in a time period of 49.3 seconds , for the specified driving conditions.

Plot 6:

Shows the Fuel Economy as Mile per Gallons for the corresponding input driving conditions.

The maximum miles that the car can run per gallon of fuel equivalent = 46 Miles,for the given vehicle at the specified driving conditions.

Case2

Simulation Condition:

The simulation is done for Hybrid electric vehicle with Wide open Throttle Drive cycle.

The Total cycle time = 100 seconds

The Top speed of this cycle = 80 mph

Time to start deceleration = 50seconds

The Grade angle - 8 Degrees

The wind velocity = 10 m/s.

plot 1:

Shows the velocity of the vehicle with respect to the Drive cycle data with the Time scale on the x axis.

The top speed of 80 mph cannot be achieved as we have some additional forces acting and so the car can only run upto 67.2 mph

The acceleration time to reach top speed of 67.2 mph = 44.5 seconds

The deceleration time from 80 to minimum = 5.06 seconds

plot 2:

Shows the changes in speed of the Engine,motor and Generator in Rpm throughout the drive cycle.

Peak Engine speed = 4676 Rpm

Peak Motor speed = 8103.5 Rpm

Peak Generator speed = 12858.5 Rpm

plot 3:

Shows the Torque characteristics and its changes of engine,motor and generator in (Nm) throughout the drive cycle.

Peak Engine torque = 139.6 Nm ; Peak Motor torque = 206.4 Nm

Peak Generator torque = 48.2 Nm

plot 4:

Shows the Battery Current values (A) and its changes for various acceleration inputs as per the Drive cycle.

The peak current discharge from the battery = 167.6A

The peak current charging to the battery = -152.46 A

Plot 5:

Shows the Battery state of charge SOC (%) and its changes corresponding to the driving inputs.

The state of charge decreased from 60% to 25.98 % of charge in a time period of 49.3 seconds , for the specified driving conditions.

Plot 6:

Shows the Fuel Economy as Mile per Gallons for the corresponding input driving conditions.

The maximum miles that the car can run per gallon of fuel equivalent = 17.93 Miles,for the given vehicle at the specified driving conditions.

Observation:

• The simulation results for both the cases is found and we can see that the simulation 1 without the inclusion of hill climbing conditions and the wind drag velocity is much more efficient when compared to the simulation which includes the hill climbing conditions and the wind drag velocity.
• The vehicle was not able to achieve the required top speed though using the highest possible current discharge of that same battery used before.
• The state of charge also shows that the discharge is also high compared to the simulation 1
• The Fuel Economy is also down to half of the previous simulation.
• So one can say, it is evident that the efficiency of no load vehicle is high compared to the vehicle with additional loads acting on them and also we have visualized this using the Powertrain blockset.

Q4

Pure Electric Vehicle:

A battery electric vehicle or pure Electric vehicle is a EV that exclusively uses chemical energy stored in rechargable battery packs with no secondary source of propulsion (e.g. hydrogen fuel cell, internal combustion engine, etc.) of energy.

BEVs use electric motors and motor controllers instead of an conventional Internal combustion engines for propulsion. They derive all power from battery packs.

So they don't produce any emission of waste gas and they are eco friendly.

They also have their own limitations such as range etc.

Example of Pure EV is Nissan LeaNow comparing both the Pure electric and Hybrid electric vehicle with the given conditions in a simulation to observe the behaviour of both the type.

Case1

Simulation Condition:

The simulation is done for pure electric & Hybrid electric vehicle with Wide open Throttle (WOT) Drive cycle.

The Total cycle time = 100 seconds

The Top speed of this cycle = 80 mph

Time to start deceleration = 50 seconds

The Grade angle = 0 Degrees

The wind velocity = 0 m/s.

plot 1:

Shows the velocity of the vehicle with respect to the Drive cycle data with the Time scale on the x axis.

The top speed of 80 mph cannot be achieved as we have some additional forces acting and so the car can only run upto 108.9mph

The acceleration time to reach top speed of 108.9 mph = 50.2 seconds

The deceleration time from 80 to minimum = 9.8 seconds

plot 2:

Shows the changes in speed of the Motor in Rpm throughout the drive cycle.

Peak Motor speed = 1123 Rpm

plot 3:

Shows the Torque characteristics and its changes of Motor in (Nm) throughout the drive cycle.

Peak Motor torque = 260 Nm

plot 4:

Shows the Battery Current values (A) and its changes for various acceleration inputs as per the Drive cycle.

The peak current discharge from the battery = 216.8 A

The peak current charging to the battery = -173.7 A

Plot 5:

Shows the Battery state of charge SOC (%) and its changes corresponding to the driving inputs.

The state of charge decreased from 80% to 75.5% of charge in a time period of 50.3 seconds , for the specified driving conditions.

Plot 6:

Shows the Equivalent Fuel Economy as Mile per Gallons for the corresponding input driving conditions.Here there is no fuel in pure electric vehicle however this gives equivalent battery energy required that of the fuel energy,and calculates the Fuel efficiency.The maximum miles that the car can run per gallon of fuel equivalent = 20.45 Miles,for the given vehicle at the specified driving conditions.

Case2

Simulation Condition:

The simulation is done for pure electric & Hybrid electric vehicle with Wide open Throttle (WOT) Drive cycle.

The Total cycle time = 100 seconds

The Top speed of this cycle = 80 mph

Time to start deceleration = 50 seconds

The Grade angle = 8 Degrees

The wind velocity = 10 m/s.

plot 1:

Shows the velocity of the vehicle with respect to the Drive cycle data with the Time scale on the x axis.

The top speed of 80 mph cannot be achieved as we have some additional forces acting and so the car can only run upto 58.9mph

The acceleration time to reach top speed of 58.9 mph = 48.8 seconds

The deceleration time from 80 to minimum = 4.63 seconds

plot 2:

Shows the changes in speed of the Motor in Rpm throughout the drive cycle.

Peak Motor speed = 6254 Rpm

plot 3:

Shows the Torque characteristics and its changes of Motor in (Nm) throughout the drive cycle.

Peak Motor torque = 280 Nm

plot 4:

Shows the Battery Current values (A) and its changes for various acceleration inputs as per the Drive cycle.

The peak current discharge from the battery = 225.8 A

The peak current charging to the battery = -163.7 A

Plot 5:

Shows the Battery state of charge SOC (%) and its changes corresponding to the driving inputs.

The state of charge decreased from 80% to 75.5% of charge in a time period of 49 seconds , for the specified driving conditions.

Plot 6:

Shows the Equivalent Fuel Economy as Mile per Gallons for the corresponding input driving conditions.Here there is no fuel in pure electric vehicle however this gives equivalent battery energy required that of the fuel energy,and calculates the Fuel efficiency.The maximum miles that the car can run per gallon of fuel equivalent = 21.45 Miles,for the given vehicle at the specified driving conditions.