English Intro72 ECTs (10 lessons)

Lesson 4

Ewen Ritchie

Agenda for 4th lesson

• Pronunciation exercises• Conducting a meeting• Writing a Report• Vocabulary

Pronunciation – Tongue twister

• Mixed metaphors muddle middling minds

Pronunciation – Tongue twister

• George Gabs grabs crabs,• Crabs George Gabs grabs.• If George Gabs grabs crabs,• Where are the crabs George

Gabs grabs?

Pronunciation – Tongue twisterCross-eyed Clara’sCrazy over crosswords,She’s got competitions on the brainWhen she’s workingEverybody’s wearyShe’s wrapped up in her dictionaryMa’s cross, Pa’s crossKing’s CrossCharing CrossEverybody’s got cross waysAnd it’s quite imposs….To avoid getting crossWith cross-eyed Clara and her crossword

craze

Pronunciation – Tongue twister

• Some say sweet-scented shaving soap soothes sore skins.

Pronunciation - Verse & poems

Limerick• ‘The order of nature,’ quoth he• ‘is wondrously brought home to me• When I think of my clock• With each tick and each tock

• Goes ‘

• (two pi times the root of one over g)

12g

π

Limerick

• The man who invented the sprocket,• Went on to develop the socket.• Then one afternoon• He went to the moon,• That’s right, he’d invented the rocket.

Pronunciation - Singing together

Pronunciation - Singing together

Reading aloud for the rest of the classAbstract - The performance and reliability of AC

Adjustable Speed Drives (ASDs) is continually improving. One of the key reasons for improvement has been the advent, development and use of Pulse Width Modulated (PWM) drives utilizing faster switching devices, primarily Insulated Gate Bipolar Transistors (IGBTs). As with many other developments, improvements in some areas may cause problems in others. An increased bearing failure rate in motors is one of the negative effects of these types of drives.

To mitigate bearing current damage in motors, as well as in loads and other auxiliary equipment attached to the motor shaft, it is important to understand how these currents are generated. In addition to theoretical explanations, actual field cases and solutions will be reviewed.

Reading aloud for the rest of the classShaft voltages exceeding 300mV require one bearing of the

motor to be insulated to prevent circulating current damage to the bearings (see Fig. 1). Typically this phenomenon only occurs on 500 frames and larger machines. Normally the Opposite Drive End (ODE) bearing is chosen. If the Drive End (DE) is insulated, the driven load can provide an electrical path that completes the loop to allow current to flow. PWM drives can cause increased circulating currents to flow due to a high-frequency flux produced by common-mode currents which link the stator, rotor and bearing loop. This is an inductive rather than capacitive effect .Motors become more asymmetrical at high frequencies because the high-frequency capacitive coupled currents depend heavily on the location of the first few turns within the slot. Since placement of the turns in random-wound motors is not well controlled by any manufacturer, even a motor which is symmetrical at low frequencies becomes asymmetrical at high frequencies.

Inductive circulating currents

Capacitive coupled current flow

Resume of lesson 3

Ethics

• Plagiarism – copying• Referencing• Claims in reports/ papers

Conducting a meeting

• Chairperson• Secretary• participant

• Agree the agenda• Discuss all points

on the agenda• Try and conclude

some of the points• Agree on work plan

for the next meeting

• Summarise the meeting

Writing a report

Components of a Report• Cover• Front Page• Preface• Contents• List of Abbreviations & Acronyms• List of symbols• Chapters• Conclusion• Appendices

Cover

• Make it Interesting!!• Title• Authors’ names and affiliation• Place• Date• Picture/ graph or something

Front Page

• Make it Informative!!• Title• Authors’ names and affiliation• Supervisor’s name• Place• Date• Abstract

Preface

• Some background– About the project– About the authors

• Target group• Reading instructions• Acknowledgements• Name and signature of the authors

List of Contents

• List of chapter and section headings with page numbers

• No more than 3 levels• List of appendices with appendix

number, title and page number• Clearly set out and edited to be

correct

List of Abbreviations & Acronyms

• The reader may not have the same definition of an abbreviation or acronym as you have

List of symbols• Optional• Must be complete and correct if

present• This list is a minefield in a report as

you may have different meanings for the same symbol

• The alternative is to use local lists in the text defining the symbols the first time they appear in e.g. each chapter

• Selection of which method to use is a matter of taste and skill

Chapters• Introduction• Description of the system to be studied• Models used• Simulation of the system response• Description of experiments• Results of experiments• Compare experimental results with

simulated results to verify that the simulation may be trusted

• Use the simulation to predict the response of a proposed real life system

• Conclusion

Introduction• Present the topic

– Why might it be interesting to study?• Review previous work by the research community

– Provides your reference for future work– Refer heavily to the references

• Discuss which future work might be useful and interesting

• Write the problem formulation• Write your objective• Review the resources you need to achieve your

objective• Review the work plan

– Conveniently expressed as a description of the remainder of the report

• Summarise the chapter

Objective

• The Objective should answer four questions:

– What will you change?– Why will you change it?– Who will benefit?– How will you change it?

Main work chapters

• Introduce each chapter– Objective of the chapter– How will this chapter be used in the project– Which other (previous) chapters will provide information

for this chapter?• Write the work of the chapter

– Referring to the references and appendices as necessary• Conclude the chapter with a summary and/or conclusion

– Have you achieved your objective for this chapter?– How will the results of this chapter be useful in the

remainder of the report• No textbook material in the chapters!

– All material should be relevant to the project• All your own work please!

– No cut and paste of other peoples work

Conclusion• Conclude the report

– List the results– Did you achieve the objective

of Chapter 1?– How will the results be

useful?– What work remains do be

done?

Appendices• Each appendix should have a meaningful

title• Each appendix should be capable of being

read independently of the report– Own objective, conclusions, references, etc.

• E.g. may use the appendices to develop system equations for use in the report

• If you do not refer to an appendix in the body of the report, the appendix is unnecessary – omit it!

VocabularyA fuel cell is a device that uses hydrogen (or hydrogen-rich fuel) and oxygen to

create electricity by an electrochemical process. A single fuel cell consists of an electrolyte sandwiched between two thin electrodes (a porous anode and cathode). While there are different fuel cell types, all work on the same principle:

Hydrogen, or a hydrogen-rich fuel, is fed to the anode where a catalyst separates hydrogen's negatively charged electrons from positively charged ions (protons).

At the cathode, oxygen combines with electrons and, in some cases, with species such as protons or water, resulting in water or hydroxide ions, respectively.

For polymer electrolyte membrane (PEM) and phosphoric acid fuel cells, protons move through the electrolyte to the cathode to combine with oxygen and electrons, producing water and heat.

For alkaline, molten carbonate, and solid oxide fuel cells, negative ions travel through the electrolyte to the anode where they combine with hydrogen to generate water and electrons.

The electrons from the anode side of the cell cannot pass through the membrane to the positively charged cathode; they must travel around it via an electrical circuit to reach the other side of the cell. This movement of electrons is an electrical current.

Parts of a Fuel Cell

Diagram of a Fuel Cell Driven Car