Week-4 Challenge WOT Condition Part-2
1.
What is the difference between mapped and dynamic model of engine, motor and generator? How can you change model type?
| Mapped Model | Dynamic model |
| In mapped models, there will be lookup tablein which we entire the essential data used for the simulation |
In dynamic model, there is no need of external data, it understands the the behaviour of the part and then it behaves accordingly, and here it is real time based data. |
In case of mapped model for Engine, Motor and generator, (ENGINE : Engine operation, power efficiency etc), (MOTOR : RPM, maximum efficienct,heat etc), (GENERATOR : Battery, torque, battery current, motor torque) all those data have to be manually entered.
In case of Dynamic model for Engine, motor and generator simulations are done on real specifications and the results can be obtained real time.
The below shown picture shows how to switch from mapped model to dynamic model
2. How does the model calculate miles per gallon? Which factors are considered to model fuel flow?
Here we are considering the power train blockset of hybrid electric vehicle.
The below show is a screenshot of blocks under visualization block where we can see the vehicle performance is calculated.
The factors considered to calculate the fuel efficiency include:
1. Vehicle speed
2. Fuel volume flow
3. Battery flow
The below shown blockset says how the miles per gallon is calculated in the power train blockset.
Miles per gallon is the distance measured in miles that a vehicle can travel per gallons of fuel.
The fuel calculation is of hybrid electric vehicle which means it have both fuel and battery.
3. Run the HEV Reference application with WOT drive cycle. Change the grade and wind velocityin the environment block. Comment on the block.
The blocktrain blockset of HEV is shown below,
Here the default drive cycle is changed to WOT (Wide open throttle) and run for T=40.
Here the drive cycle is changed to WOT.
The performance plot obtained after the simulation is shown below (There is no change in Grade and wind).
Plot 1 : Trace velocity target vs Actual (mph).
(here with Grade = 0, The actual velocity meets the desired velocity.)
plot 2 : Engine speed,Motor speed and generator speed (RPM).
(The achieved motor and engine speed can be analysed here)
Plot 3 : Engine torque, motor torque and Generator torque (Nm).
(It shows the Torqe analysis of motor, engine, generator.)
Plot 4 : Battery current (A).
(It shows how much ampere is taken from the battery.)
Plot 5 : Battery SOC.
(the anasysed SOC data can be fetched frm here.)
Plot 6 : US Fuel economy MPGe.
(It shows the fuel efficiency.)
Here in the environment block the Grade and wind is changed to a different constant value say Grade = 5 and wind = 10.
The plot after simulation with changed Grade and wind is shown below.
plot 1 : Trace velocity Target vs Actual speed.
Here Grade constat is changed to 5 and the actual speed cannot reach the required speed.
Plot 2 : Plot for Engine speed, Motor speed and Generator speed in (RPM).
Plot 3 : Plot for the Engine torque, Motor torquw and generator torque (Nm).
Plot 4 : Plot for Battery current (A).
Plot 5 : Battery SOC.
Plot 6 : Us Fuel Economy MPGe.
4.Keeping all other parameters same compare the simulated results of hybrid and pure electric powertrain.
Here we use power train blockset of HEV. All the data are Kept constant and run at T=40.
Here the powertrain blockset is of EV and the performance and FE scope is shown below
here we can conclude that the difference in behicle operation of EV has only the battery as its power sourceand the HEV has Engine and Batter as the power source. The Charts of different parameters are varried according to it.