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?

ANSWER:-

MAPPED MODEL FOR MOTOR/GENERATOR:-

• It is a type of block where the input parameters are already assigned in lookup tables.
• The torque required for the engine or motor is has been sensed and the same blocks(engine or motor) blocks itself generates the required torque output just as required.

EXAMPLE:-

• That we can say simply as it does not respond on the real time motor and engine parameters.
• The values which we are obtaining as an output will be stored from the corresponding input parameters.
• The actual advantage of this model is it doesnot run at high speed but actually it runs in less time and it doesnot depends upon the real time parameters of input blocks.

DYNAMIC MODEL OF MOTOR/GENERATOR :-

• Dynamic model means it generates outputs using various input subsystems .
• this model is opposite to mapped , it runs by real time simulation where the required input from the drive cycle is taken
• And for that individual real time simulation gets performed and summing all the results of the subsystm gives the output for the simulation.

EXAMPLE:-

• From the vehicle fedback the inputs for drive cycle requirements the initial voltage, and current is given.
• As it considers the real time outputs from the subsystem it may consider as more accuracy than the mapped model .
• It takes too much time why because it has too many subsystems , it has to simulate various sperate subsystem blocks of engine and motor.

How to select the Type of model:-

1. In the Powertrain Blockset we need to select the type of vehicle say electric vehicle or hybrid electric vehicle or fully engine vehicle.
2. After appearing the simulink model appears by showing the work flow blocks of the model,
3. In that we need to go to passenger block electric plant - EV motor/gen block.
4. After moving into this block just right click and go to variance label mode active choice motorgenv mapped or dynamic.

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

ANSWER:-

• Miles per gallon is a measurement of fuel economy where it is determined by how long a car is travelled with a gallon of petrol/diesel for engine.
• If it was an electric vehicle we can say the energy which is equivalent that of a engine powered carto propel distance covered by the car.
• its actually the amount of fuel say petrol/deisel is required by a car to travel for a some distance
• And then the same situation is compared by an electric car then the amount of electric energy required totravel for same distance is expressed as miles per gallon.
• And this block can calculates the miles per gallon for types of vehicles.
• The below model takes the speed of vehicle , fuel flow and battery power is taken as input to calculate the fuel consumption and the equivalent battery consumpton and calculates the miles per gallon.

VEHICLE SPEED AND FUEL FLOW:-

• For Fuel consumption the vehicle speed is mandatory to take into consideration at that particular time.
• So to determine the fuel consumption throughout the drive cycle.

• we used integrator block to convert the speed to distance with the time and we are doing the same of converting the velocity to get distance covered by integrating.
• the fuel flow is expressed as mass flow rate , the fuel used at each moment in kg/sec.
• now integrating this will result in the mass of the fuel and by using it we can convert samevolume by multilying 1000 to get into litres.
• we can now get the result from comparing the two results.

Battery Power:-

• we convert power from watts into kw by divide by 1000.
• The required energy from battery to move the vehicle is equavalent to that of the engine is found is here.
• the power is converted into energy by multiplying by 1000.
• then the energy (kwh) is converted into US gallon by dividing with 33.7.

• 

• then we can get energy in US gallons. we convert the us gallons from hours to sec by dividing by 3600
• we multiply 0.003785 with the value we found
• Then the final fuel flow in (mA3 /s) we multiply with 739 which gives the result of mass flow rate in kilograms.
• to find the equivalent us gallons energy and estimate the miles per gallons we given the battery energy equivalent as an input.

TO CALCULATE MILES PER GALLON:-

• Our input speed in meters is converted into miles by multiplying with 0.000621
• after the input energy is converted into us gallon by multiplying with 264.172 .
• at final the two inputs miles covered and us gallon is both divided and we get the results in miles / gallon.