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 ?

powertrain blockset provides two types of combustion engine models
1)mapped 2)dynamic

Mapped engines represent macro engine behaviour as a set of lookup tables(brake torque,fuel flow,air mass flow,exhaust temperature,efficiency and emmisions) as functions of comanded load and measured engine speed.

Dynamic speed decomposes engine behaviour into individual component models that account forengine dynamics,most notably intake airflow and turbocharger dynamics.

You can switch between engine model types based on yoiur application.

Dynamic engine models are suitable for designing control,estimator, and diagnostic algorithms that depend on dynamic subsystem states,for example, in closed-loop AFR control algorithm develeopment.

Mapped engine modules are suitable for analysis and design activities that do not require engine subsystem,dynamic characteristics, for example in engine and transmission powertrain matching analysis for suel economy,emissions and perforamnce tradeoffs

Mapeed model : It is based on lookup tables.it is a steady statemodel and similution takes less time due to simplicity when compared to dyanmic model.

Dynamic model : It is based upon actual component model.Each component is modeled seperately and simulation takes more time due to complexity.

Mapped engine diagram :

Dynamic engine diagram :

Mapped and Dynamic model of CI/SI Engine :

Dynamic Model of SI engine :

Mapped SI engine model :
The Mapped SI engine block implements a mapped sapark-ignition(SI) engine model using power,air mass flow,fuel flow,exhaust temperatureand emission performace lookuptable you can use the block for:
. Hardware_in_the_loop (HIL) engine control design
. Vehicle_level fuel economy and performance simulations

The block enables you to specify lookuptables for these engine characteristics.The lookup tables for these engine characteristics. the lookup tanle developed the modelbase calibration toolboxare functtions of commanded torque Tcmd brake torque,Tbrake,and engine speed N.if you select input engine temperature,the tables also a function of engine temperature

Dynamic stage SI model:
The SI core engine block implements a spark-ignition (SI) engine from intake to exhaust port.you can use the block in large vehicle models,hardware-in-the-loop(HIL) engine control design,or vehicle fuel level economy and performance simulations

The SI core Engine block calculates :
. Brake torque
. Fuel flow
. Port gas mass flow,including exhaust gas recirculation (EGR)
. Air-fuel ratio (AFR)
. Exhaust temperature and exhaust mass flow rate
. Engine-out (EO) Exhaust emmisiions
         Hydrocarbon (HC)
         Carbon monoxide(co)
         Nitric oxide and nitrogen dioxide (N2O)
         Carbondioxide(CO2)
         Particular matter(PM)

Mapped CI engine model :
The mapped CI engine model block implements a mapped compression ignition (CI) engine model using power,air massflow,fuel flow,exhaust temperature efficiency and emmission performance lookup tables. you can use the block for
. Hardware-in-the-loop (HIL) engine control design
. Vehicle-level fuel economy and performance simulations.
The lookuptables developed with the model based calibration toolbox are functions of injected fuel mass F, engine torque T,engine speed N engine temperature T

Dynamic CI engine model :
The CI core engine block implements a compression ignition(CI) engine from intake to the exhaust port.you can use the block for hardware-in-the-loop(HIL) engine control design or vehicle-level fuel economy and performance simlations.
The CI core engine block calculates :
. Brake torque
. Exhaust temperature
. Airfuel ratio (AFR)
. Fuel pressure
. Engine out (EO) exhaust emmisions:
      Hydrocarbon (HC)
      Carbon monoxide(CO)
      Nitric oxide and nitrogendioxide(N2O)
      Carbon dioxide(CO2)
      Particular matter(PM)

Now to change the model from Mapped >> Dyanamic or Dynamic >> Mapped

Dynamic >> Mapped :
To change the model type we can do the changes with the help of the variant manager.we have to select the model which we have to activate/use in the simulation.After this we haver select subsystem&model reference >>convert to>> variant system now we can see a option added variant select that and now open the variant select that and now open the variant manager and from their you can observe the model is selected by default right click on that and from their select option set as label mode active choice

Inside view of mapped motor :

The Mapped motor block implements a mapped motor and drive electronicsoprating in torque control mode the output tracks the torque reference diamond and includes a motor response and the drive response time constant .Use the block for fast system level simulations when you do not know detailed motor parameters for example for motor and power tradeoff studies.The block assumes that the speed fluctuations due to mechanical load do not affect the motor torque tracking.

we can specify :
. port configuration-input torque or speed
. Electrical torque range-Torque speed envelope or maximum motor power and torque
. Electrical loss- single operating point,measured efficiency or measured loss. if you have model-based callibration toolbox,you can virtually calibrate the measured loss tables.

Insided view of dynamic motor :

By default a flux-based PMSM motor is used for simulation :
. rotor shaft torque
. rotor shaft speed
. stator terminal voltage
outputports/values used for simulation :
. bus signal
. phase a,b,c current
. motor torque
. motor speed

Mapped and dynamic model of the generator :

Inside view of Mapped generator :

 

Inputports/values used for simulation:
. generator torque demand
. generator speed
. bus voltage
Outports/values used in the simulation :
. generator torque
. generator current

Inside view of dynamic generator :

by default a flux based PMSM motor/generator is used for simulation :
Input ports/values used for simulation:
. generator shaft torque
. generator shaft speed
. stator terminal voltage
Output ports/values used for simulation :
. bus siignal phase a,b,c current
. generator torque
. generator speed

2)How does the model calculate miles per gallon ? which factors are considered to model fuel flow ?

Miles per gallon equivalent to the measure of the average distance travelled per unit of energy consumed. MPGe is used by the united states Environmental protection Agency (EPA) to compare energy consumption of alternative energy vehicle,plug-in electric vehicle and other advanced technology vehicles with the energy consumption of conventional internal combustion vehicles rated in miles per U.S.Gallon

To calculate the miles per gallon, we have to convert all of the battery powerin to gallons,this is defined by united states environmental protection agency (EPA) as 33.7 kilowatt-hours of electricity is equal to 1 gallon of gas

MODEL OF HEV :

we can get the fuel economy from the visualization block :

inside the block performance calculations :

-To calculate the fuel economy in miles per gallon(MPG) we need to consider the values 1. vehicle speed 2. fuel volume flow

-To calculate the vehicle speed of the value A speed value is inputed which is then durther calculating using math equations,after this we get the value in meter which is then converted in -to miles by multiplying the value by 0.000621371

-To calculate the fuel flow, the volume of the fluel flow is entered is considered which is converted from m^3to US gallon by dividing with 264.172.

3)Run the HEV reference application with WOT drive cycle. change the grade and wind velocity in the environmental block.

In the given data we have to import the HEV reference application file from the powertrain blockset .we have to run the simulation by using wide open throttle (WOT) drive cycle.Assumptions taken wind velocity =8;grade angle = 12

HEV MODEL :

 

Main components :
-SI/CI engine
-geartrain(Box
-clutch
-differential
-electric motor
-generator
-battery
-wheel and brake
The IC engine arrangement is in series where as the electrical motor arrangements is in parallel

DRIVE CYCLE selected : WOT(Wide Open Throttle) for 100 seconds

 

parameters updated>>Environment>>Grade& wind velocity :

OUTPUT RESULTS :

we have considered as grade angle =12 ;wind veociity = 8;
simulation time = 100seconds;WOT deceleration = 25 seconds;

we can observe from the output result that when the full throttle is been given for 25 seconds the maximum speed of 37.9 mph is achieved at time frame of 19.899 seconds,after 25 seconds time period the vehicle deceleration upto 100 seconds

we also observe the battery soc falls upto 68% to reach the wot 25 seconds as soon as the vehicle deceleration starts the regenrative braking system is enabled we can observe the rise in the battery soc 80%we observe the battery draws current around 500 amps upto 25 seconds whereas during deceleration it gets charged around 220 amps and stops charging when the engine is turned OFF

4)Keeping all other parameters same,compare the simulated results of hybrid and pure electric power trains

Given data :we have to import the EV Reference application file from the powertrain blockset.we have to run the simulation by using wide open throttle drive cycle
Assumptions : Grade angle= 12 ;windvelocity = 8

EV model:

 

Main components :
-Electric motor
-Geartrarin(box)
-Battery
-Differential
-Wheel and brake

--Drive cycle selected :- wide open throttle (WOT) for 100 seconds

OUTPUT results of EV model :

we have considered Grde angle =12 ; windvelocity = 8;simulation time= 100seconds; WOT deceleration = 25 sec

we can observe from the output result that when the full throttle is been given for 25 seconds the maximum speed of 42.53mph is acheived at time frame of 23.800 seconds,after 25 seconds time period the vehicle decelerates upto 100 seconds

we also observe the batry soc falls falls upto 76% to reach the WOT(25seconds) as soon as the vehicle deceleration starts the regenrative braking system is enabled we can observe there is less amount of current is produced so the graph remain constant

we observe that the battery draws current around 200 amps upto 25 seconds whereas during deceleration it gets changed around 120amps and stops charging when the electric motor is turned OFF.

Output results of HEV model:

 

The first difference observed in the speed the Hev acheived 37.9mph at 19.899 seconds whereas the EV acheived 42.53mph at 23.80 seconds here we can say the EV is more efficient due to less complexity and the power source keeps on changing according to the speed of the vehicle

The second difference observed was in the amount of the battery SOC in the case of HEV it went down upto68% and once the vehicle deceleratesthe regenerative braking system is activated we can observe the battery soc ring to 80% whereas in the case of EV it went down upt0 76% which was less compared to hev but when the vehicle decelerates the regenrative system activated the amount of current produces is very less we can observe in the graph as there is no seperate generator through which the battery can charge & in the case ec of the battery gets on depleted till its empty.