EEE8155 Designing Sustainable Electric Propulsion and Generation Systems: Assignment 1
Weighting: 40% of module
1. Introduction
This is the first of two assignments for the module Design and Analysis of Electrical Machines and Drives, EEE8015.
The assignment involves you choosing an application for an electrical motor drive and designing a sine wave
permanent magnet motor for that application. The design will be produced using basic calculations, rather than using a commercial motor design tool.
In this assignment we are seeking to evaluate how well you:
• understand the fundamentals of electrical machine design.
• are able to produce a high level specification.
• produce an outline design using analytical calculations and appropriate approximations.
• perform. a critical analysis of your design.
You have to produce a report detailing your reasoning, calculations presenting the design. The final report (.pdf) is due on Monday 22nd April 2024 and must be uploaded to Canvas.
Please follow the name format for your submission of two documents.
Format: Last Name_First Name_Student ID_Assignment1.pdf. For example, John_Smith_B123456_Assignment1.pdf
2. What you need to do
Choose an application. This can be anything which involves an electric motor drive. The only applications which are NOT allowed area propulsion drive for an electric car or an electric drill, as examples have been covered in class.
You will then:
(a) Produce a specification, based around typical requirements for such an application, referencing any sources used. The specification will also say whether the drive is connected to the output via a gearbox. Try and base your specification to be as close to the real application as possible. Your specification must include speed, power and dc supply voltage to the inverter.
(b) You must now design a 3 phase PM machine to meet the specification. Within this you may:
• Decide upon magnetic and electric loadings and thengo on to choose the rotor dimensions.
• Decide, with reasons why, your choice of pole number.
• Decide the magnet material and characteristics.
• Choose a suitable air-gap length.
• Determine your magnet thickness and pole arc.
• Decide upon the number of slots and the winding type, along with winding factors.
• Choose the required back emf and hence the number of series turns per phase to achieve this.
• Determine the tooth width and core back depth.
• Decide upon your wire diameter and then the slot depth.
• Draw a sketch of your design and comment upon whether you think it could be improved.
• Perform. any other calculations which you think are appropriate, such as efficiency estimates, thermal predictions etc.
3. Report and Marking Scheme
The overall breakdown of marks is
10% Report: Style. / presentation / quality of language
20% Specification: Specification and sourcing of information
60% Main Design: Choices made, calculations performed, clarity of thinking and any additional material presented.
10% Conclusions Including critique of your design and statements about how it may be further improved.
The report must be less than 8 pages (excluding title / contents page, appendices and references)
4. Marks Awarded
Marks awarded will typically reflect the following assessment of the report:
Pass (50-60%)
A good report which has a sensible application and derives an appropriate specification. Choice of parameters made, with reasons given and appropriate calculations shown. Some discussion.
Merit (60-70%)
A very good, well presented report, with a clear specification produced using good references, showing a significant amount of background work. Well reasoned choice of parameters and calculations made, along with an insightful analysis and discussion of the results.
Distinction (>70%)
As in a merit, with some additional calculations and insight beyond what is asked for above. High quality discussion of results and commentary on how the design could be refined.
5. Warning
In recent years we have found that a few students have clearly used an external source to help them complete this assignment. You must not:
(a) Use an external person or website to do the work for you - we can tell!
(b) Copy reports from previous years - we will check!
(c) Use equations which have not been used in your notes without demonstrating that you completely understand them. If you do so, it is only acceptable if you reference the source and define all symbols used.
All relevant equations should be available in your notes. Students who ignore this warning are very likely to fail.