Week-4 Challenge WOT Condition Part-2

AIM: To run WOT Drive cycle and answer the following questions.

OBJECTIVE:

1. What is the difference between mapped and dynamic model of engine, motor and generator? How can you change model type?
2. How does the model calculate miles per gallon? Which factors are considered to model fuel flow?
3. Run the HEV ReferenceApplication with WOT drive cycle. Change the grade and wind velocity in the environment block. Comment on the results.
4. Keeping all other parameters same, compare the simulated results of hybrid and pure electric powertrains.

1.

Mapped

• Mapped engines represent macro engine behaviour as a set of lookup tables that are brake torque,fuel flow,air mass flow,exhaust temperature,efficiency and emmisions as functions of commanded load and measured engine speed.
• The mapped engine model is generally faster while operating.
• Mapped model can be simply referred to a static system.

Dynamic

• Dynamic engines decompose engine behaviour into individual component models that account for engine dynamics,most notably intake air flow and turbocharger dynamics.
• There sre suitable to run diagnostics or controlling design parameters and are suitable for running.
• The dynamic model is usually slower while operating.

You can change the model type by following steps

open the blockset model of the vehicle and click on the vehicle block and go to electrical part and then click on the motor or generator and select the variant and change according to you choice.

2.

In performance calculations there are three inputs thet ara

1. vehicle speed
2. fuel flow
3. battery power

The battery power is converted to gallon and vehicle speed to miles you can see it in last step.

battery power is divided by 1000 w per kw and the result is again divided by 33.7 to gallon per hour and then hours is converted to second that is divided by 3600 and finally we get in m^3 per gallon .

3.HEV ReferenceApplication with WOT drive cycle.

This is the blockset of HEVM with WOT drive cycle.

WOT block parameters are show in the above image.

By clicking on the environment block we get this and let us give grade value 5 and wind value 10.

• without any grade and wind values

• After giving grade value 5 and wind value 10.

By comparing both the results we can observe the following things.

1. In the first case the maximum speed is more than 100mph but in the second case the max speed is less than 100 that means the grade and the wind effects the speed of the vehicle.
2. And also the US fuel economy more in first case compered to second case.
3. Deceleration time in first case is more than the second case.

4. By keeping all other parameters same

1.HEVM performance

2. EV PERFORMANCE

1. In the HEVM the maximum speed is more than EV vehicle.
2. And also the US fuel economy more in EV compered to HEV.
3. Deceleration time in EV is more than the HEV .
4. In EV there is no pollution.