Task and Mark distribution:
You are asked to design and engineer a fully battery electric powertrain in order to meet some specific design criteria using model based design approach. The specification of the vehicle is as follows:
Mass : 1000kg + [the last 3 digits of your SID]
Total aerodynamic drag coefficient: 0.3
Tire size: 185/65R14
The rolling resistance is 0.015
The typical efficiency maps for different types of electromotors are given as attached files in AULA.
The vehicle is required to have an acceleration of 8 s for 0-100km/h in horizontal road.
In the following brief MD is Motor-Drive and VD is Vehicle Dynamics.
According to the serial hybrid architecture, evaluate the required specification for the motor(S), transmission, generator and battery. For each section, take in to the account the followings:
1)Motor-drive(s): (10%)
Calculate the required rating power for motor-drive based on the required acceleration time, find the transmission ratio and also the number and the type of the connection of motor to the wheels.
For the selected motor-drive, your report should comprised:
The calculation (procedure of selection)
Brand of selected moror
Type (IM, SMPM, IMPM,…)
Required DC voltage supply
Rated power
Rated torque
Maximum speed
Base speed
Maximum current
Hint: You need to calculate the required power based on the formulas given in lectures.
2)Battery: (20%)
Based on the required DC voltage and power requirements of the selected motor-drive(s), design the battery pack. The final design of the battery pack should comprise the following items:
The calculation process for battery selection (Relevant to each of the following items)
The type of battery cells used in the battery pack
The number of battery cells in parallel and series configuration
The capacity of the whole battery in Ah
Show the characteristic maps of cell and battery ( and )
Calculate the maximum attainable current of battery
Hint: The voltage of battery pack is dictated by the MD requirement, also the battery should be able to provide at least the maximum current (and power) needed by the electro motor.
3)Powertrain model development : (40%)
Based on the selected items (motor-drive and battery) and other technical properties of vehicle, develop a proper model in MATLAB/Simulink comprising MD/VD. Your model should comprises of the followings block/considerations:
Motor-drive block based on efficiency map modelling approach, use the scaling method to fit the typical efficiency maps to the selected MD
Battey model (Use a simple R-int modelling approach), assume that initial SoC of battery is 90%
Tire model and vehicle dynamics block
Take into the account the efficiency of transmission (between engine and generator/between MD and tyres, if needed)
After developing the model, you should test the developed model based on the following conditions; Apply maximum torque command to the MD, plot the desired diagrams and find the characteristics based on model result.
Plot the V-t plot
Plot the SoC-t plot
Plot the i-t plot (Battery current vs. time)
The maximum attainable speed
The 0-100km/h acceleration
Hint: For each model block, discuss the modelling approach and support your modelling report by the proper governing equations. Also, discuss the results and try to support your discussion by proper sensitivity analysis i.e., how changing in different parameters can affect the final results (max speed and acceleration).
4)Model simulation under driving cycle (30%)
Considering the vehicle is utilized just with a regenerative brake, use a proper PI or PID controller and tune the parameters to control the vehicle longitude speed to track a predefined speed profile (Driver model).
Using the FTP-75 (Federal Test Procedure) as the setpoint for vehicle speed, report the followings:
Plot the generated torque of motor as a function of time
Plot the MD current as a function of time
Plot the level of SoC as a function of time
Calculate the energy consumption (kWh/100 km) based on the cycle result.
Calculate the milage of vehicle based on the driving cycle. (You may need to expand the cycle so that the charge in the battery reaches 0%)
You need to describe each plot and discuss the result.
Modelling considerations:
The software to be used is MATLAB/Simulink
The starting capacity of the battery for the drive cycle is 90%
Report considerations
This is an engineering report requiring adequate formatting.
Marks will be allocated for referenced material and appropriate discussion. Estimations of fuel consumption and acceleration results according to literature will not be accepted. The motor/generator efficiency maps should be considered based on the maps provided in AULA. ALL results must be referenced from your submitted models. Battery SOC must be demonstrated how it is changing during the drive cycle as without it the model is considered incomplete. Every objective component must be clearly identified in the report. All relevant data must be in the report for marking.
Notes:
1. You are expected to use the Coventry University Harvard Referencing Style. For support and advice on this students can contact Centre for Academic Writing (CAW).
2. Please notify your registry course support team and module leader for disability support.
3. Any student requiring an extension or deferral should follow the university process as outlined here.
4. The University cannot take responsibility for any coursework lost or corrupted on disks, laptops or personal computer. Students should therefore regularly back-up any work and are advised to save it on the University system.
5. If there are technical or performance issues that prevent students submitting coursework through the online coursework submission system on the day of a coursework deadline, an appropriate extension to the coursework submission deadline will be agreed. This extension will normally be 24 hours or the next working day if the deadline falls on a Friday or over the weekend period. This will be communicated via your Module Leader.
6. Assignments that are more than 10% over the word limit will result in a deduction of 10% of the mark i.e. a mark of 60% will lead to a reduction of 6% to 54%. The word limit includes quotations, but excludes the bibliography, reference list and tables.
7. You are encouraged to check the originality of your work by using the draft Turnitin links on your Aula Web.
8. Collusion between students (where sections of your work are similar to the work submitted by other students in this or previous module cohorts) is taken extremely seriously and will be reported to the academic conduct panel. This applies to both courseworks and exam answers.
9. A marked difference between your writing style, knowledge and skill level demonstrated in class discussion, any test conditions and that demonstrated in a coursework assignment may result in you having to undertake a Viva Voce in order to prove the coursework assignment is entirely your own work.
10. If you make use of the services of a proof reader in your work you must keep your original version and make it available as a demonstration of your written efforts.
11. You must not submit work for assessment that you have already submitted (partially or in full), either for your current course or for another qualification of this university, unless this is specifically provided for in your assignment brief or specific course or module information. Where earlier work by you is citable, ie. it has already been published/submitted, you must reference it clearly. Identical pieces of work submitted concurrently will also be considered to be self-plagiarism.
