View
106
Download
0
Category
Preview:
Citation preview
DEPARTMENT OF ELECTRICAL AND INFORMATION ENGINEERING
FACULTY OF ENGINEERING
UNIVERSITY OF RUHUNA
INDUSTRIAL TRAINING REPORT SUBMITTED IN PARTIAL FULFILMENT
OF THE DEGREE OF BACHELOR OF SCIENCE IN ENGINEERING
27st April 2016
VEGA TECHNOLOGY, CODEGEN
INTERNATIONAL (PVT) LTD
(From 4th January 2015 to 25th March 2016)
MADHURANGA S.H.R (EG/2012/1986)
2 | P a g e
PREFACE
This report was prepared in relation to the second Industrial Training Program
for Engineering Undergraduates conducted by University of Ruhuna. The training
period was 12 weeks at VEGA Technology, CodeGen International (Pvt) Ltd.
This report consists of four main chapters. The report starts with an introduction
to CodeGen International (Pvt) Ltd. The history of the company, vision and mission,
organizational structure, and the strengths of the company that I observed during my
training period are described in the first chapter of the report.
My training experiences regarding technical facts are described in the second
chapter. I have explained about the things that I learnt at different worksites. Here my
objective was to give the basic idea about each technological fact and how they are
applied in practice.
In the third chapter I explained the experiences I got regarding management.
VEGA is a project of CodeGen International (Pvt) Ltd and it is an idea of Dr. Harsha
Subasinghe, who is the co-founder and CEO of CodeGen International Group of
Companies.
I used fourth and final chapter of this report to give a summary of my training
period, what I learnt and my experiences as a trainee. I conclude my report with a
description about the importance of this training and how it would be beneficial for my
future. Finally I included the sources that I referred in preparing this report.
I had good experience about motor controlling, isolated temperature, current &
voltage sensor and power electronics trouble shooting and debugging in VEGA car. As
an engineering student I was lucky to have this valuable and rare chance to have my
second industrial training experience at VEGA Technology, CodeGen Internationa
(Pvt) Ltd where I was able to gain great work place experience and technical
knowledge.
Madhuranga S.H.R.
EG/2012/1986
Department of Electrical and Information Engineering,
University of Ruhuna.
3 | P a g e
ACKNOWLEDGEMENT
I would like to thank some persons and organizations who really helped me
during the training period. First of all I take this opportunity to express my profound
gratitude and deep regards for Director Dr.J.M.R.S Appuhami who coordinated and
guided us in selecting training places and taking all the arrangements to make it more
successful. And also I express my deep regard for Dr.Keeerthi Gunawickrama, Head
of the Department, Electrical & Information Engineering and all the academic and
none-academic members of my faculty who associated to arrange my industrial training
at VEGA Technology, CodeGen International (Pvt) Ltd.
My sincere gratitude goes to Engineering Education Center of Ruhuna
Engineering Faculty for giving me this opportunity and also to NAITA for granting us
for the training.
I convey my special thanks to Electrical Engineer Mr. Shiranga Ariyasinghe, the
firmware developer & designer of VEGA car at VEGA Technology who arranged my
Training Plane. And also I would like to thank VEGA team leader and Research
Scientist, Dr. Beshan Kulapala. Electrical Engineer Mr. Supun Amarasinghe,
Electronic & Telecommunication Engineer Mr. Pabasara Karunanayake, System
Engineer Mr. Ruwan and all the other staff members in electrical & electronics,
software & firmware and mechanical.
My heartiest gratitude goes to my parents, my sisters and friends who helped
me a lot to make my industrial training a success .The blessing, help and guidance given
by them time to time shall carry me a long way in the journey of life on which I am
about to embark.
Thank you.
Madhuranga S.H.R.
EG/2012/1986
Department of Electrical and Information Engineering,
University of Ruhuna.
4 | P a g e
Contents
Chapter One ................................................................................................................. 9
Introduction to the Training Establishment.............................................................. 9
1.1 Company Profile. ............................................................................................ 9
1.1.1 Introduction. ............................................................................................. 9
1.1.2 Vision. .................................................................................................... 10
1.1.3 Mission. .................................................................................................. 10
1.1.4 History.................................................................................................... 11
1.1.5 Awards. .................................................................................................. 11
1.2 Organization Structure. ................................................................................. 12
1.2.1 Organization Structure of CodeGen (Pvt) Ltd. ...................................... 12
1.2.2 Organization Structure of VEGA Team. .................................................... 14
1.2.3 Working culture and people ........................................................................ 15
1.2.4 Company values .......................................................................................... 15
1.2.5 Products and services of CodeGen International (Pvt) Ltd. ....................... 16
1.2.6 Strengths. .................................................................................................... 20
1.2.7 Weaknesses. ................................................................................................ 21
1.2.8 Suggestions to overcome Weaknesses. ....................................................... 21
1.2.9 Opportunities............................................................................................... 22
1.2.10 Threats....................................................................................................... 22
Chapter Two ............................................................................................................... 23
Technical Details. ....................................................................................................... 23
2.1 Introduction to VEGA Project. .......................................................................... 23
2.2 Introduction Electric vehicles (EV) and inside of an EV. ................................. 26
2.3 Introduction to my training experience. ............................................................. 30
2.3.1 PCB designing. ........................................................................................... 30
2.3.2 Motor driver board was designed using VLA500-01 gate-driver ............... 32
.............................................................................................................................. 34
2.3.3 Motor driver board was re-designed using VLA503-01 gate driver and
VLA106-15242 DC-DC power supply. ............................................................... 37
2.3.4 The gate resistor board was designed according to driver board dimension.
.............................................................................................................................. 41
2.3.5 Collected information and created report about isolation amplifiers. ......... 42
2.3.6 Designed and Simulated temperature, voltage and current sensors using
TINA-TI. .............................................................................................................. 43
2.3.7 Participated for PCBs fabrication using UV light....................................... 51
2.3.8 Participated for the new gate driver experimentations and debugging ....... 55
2.4 Why electric vehicles are popular in the present ............................................... 56
5 | P a g e
2.5 Advantages of EV .............................................................................................. 57
2.6 Disadvantages of EV.......................................................................................... 57
Chapter Three ............................................................................................................ 59
Management Details .................................................................................................. 59
3.1 Training experience - management .................................................................... 59
3.2 Office practice .................................................................................................... 59
3.3 Safety procedures ............................................................................................... 60
3.4 Financial management ....................................................................................... 60
3.5 Management ....................................................................................................... 60
Chapter Four .............................................................................................................. 62
Summary and Conclusions ....................................................................................... 62
4.1 Summary ............................................................................................................ 62
4.2 Conclusions ........................................................................................................ 63
References ................................................................................................................... 64
Abbreviation ............................................................................................................... 65
6 | P a g e
LIST OF TABLES
Chapter Two………………………..………………………………...23
Table 2.1: Comparison of ACPL-782T and ACPL-C87X…………………………43
7 | P a g e
LIST OF FIGURES
Chapter One…………………………………………………………...……09 Figure 1.1: Company Logo………………………………………………………….……..09
Figure 1.2: VEGA Technology’s Logo…………………………………………….……....09
Figure 1.3: CodeGen Hierarchy………………………………………………………….....13
Figure 1.4: Organization structure of the VEGA team………………………………….…14
Figure 1.5: TravelBox Product Banner……………………………………………….…....17
Figure 1.6: Ru-Bank Logo…………………………………………………………….…...17
Figure 1.7: Destination Management Product Banner………………………………….….18
Figure 1.8: Zoom Sri Lanka Logo…………………………………………………….……18
Figure 1.9: Savaree Banner…………………………………………………………….…..18
Figure 1.10: The SolidWorks model of the car designed by VEGA……………............…20
Chapter Two………………………………………………………………...23
Figure 2.1: Final design of the VEGA car…………………………………………………23
Figure 2.2: Motor controller design of VEGA car…………………………………………24
Figure 2.3: Battery pack design of VEGA car……………………………………………..24
Figure 2.4: Level One charger……………………………………………………………..25
Figure 2.5: Level Two charger……………………………………………………………..25
Figure 2.6: Level Three charger……………………………………………………………25
Figure 2.7: ChargeNET membership card…………………………………………………26
Figure 2.8: The image of a permanent magnet synchronous motor that is used by electric
cars…………………………………………………………………………….27
Figure 2.9: Two motor controllers of VEGA car…………………………………………..28
Figure 2.10: The image of an IGBT that is use by VEGA………………………………...28
Figure 2.11: DC-AC inverter using six IGBTs…………………………………………….29
Figure 2.12: Designed schematic of VLA500-01 gate driver using eagle library editor…..33
Figure 2.13: Designed package of VLA500-01 gate driver using eagle library editor…….33
Figure 2.15: Single side schematic of the dual mode gate driver board using
VLA500-01 gate driver………………………………………………………34
Figure 2.15: Single side PCB layout of the dual mode gate driver board using VLA500-01
gate driver……………………………………………………………………35
Figure 2.16: Image of VLA503-01 hybrid integrated gate driver…………………………38
Figure 2.17: Designed schematic of VLA503-01 gate driver using eagle library editor….38
Figure 2.18: Designed package of VLA503-01 gate driver using eagle library editor……38
8 | P a g e
Figure 2.19: Image of VLA106-15242 hybrid integrated DC-DC power supply………….39
Figure 2.20: Designed schematic of VLA106-15242 hybrid integrated DC-DC power
supply using eagle library editor……………………………………………..39
Figure 2.21: Designed package of VLA106-15242 hybrid integrated DC-DC power
supply using eagle library editor…….....…………………………………….39
Figure 2.22: Single side schematic of the dual mode gate driver board using
VLA503-01 gate driver………………………………………………………40
Figure 2.23: PCB layout of the dual mode gate driver board using VLA503-01 gate
driver…………………………………………………………………………41
Figure 2.24: Gate resistor board……………………………………………………………42
Figure 2.25: Output voltage vs Input voltage of ACPL-C87B…………………………….44
Figure 2.26: Voltage sensor using ACPL-C87B isolation amplifier and OPA350
operational amplifier…………………………………………………………45
Figure 2.27: Input signal vs Output signal of the ACPL-C87B……………………………46
Figure 2.28: Vin(+) and Level shifted Vin(+) using first op-amp…………………………47
Figure 2.29: Vin(-) and inverted buffer amplified of Level shifted Vin(-) using
second op-amp……………………………………………………………….47
Figure 2.30: Level shifted output through third op-amp…………………………………...48
Figure 2.31: Current sensor using ACPL-C87B isolation amplifier and OPA350
operational amplifier………………………………………………………....49
Figure 2.32: Temperature sensor using ACPL-C87Bisolation amplifier and
OPA350 operational amplifier……………………………………………….50
Figure 2.33: A PCB layout that printed on transparent paper……………………………...51
Figure 2.34: Removing sticker on the presensitized positive photoresist copper clad
board…………………………………………………………………………52
Figure 2.35: UV bulb that used in VEGA…………………………………………………52
Figure 2.36: Exposing the Board using UV bulb at VEGA……………………………….52
Figure 2.37: positive developer……………………………………………………………53
Figure 2.38: Liquid ferric chloride………………………………………………………...54
Figure 2.39: PCB drilling………………………………………………………………….54
Figure 2.40: A new gate driver board using TOSHIBA TLP5214 gate driver…………….55
Figure 2.41: A new gate driver experimentation…………………………………………..55
9 | P a g e
Chapter One
Introduction to the Training Establishment.
1.1 Company Profile.
1.1.1 Introduction.
CodeGen is one of the largest software companies in Sri Lanka, specialized in
providing software solutions in the Travel Industry. Some of the world's largest airlines,
cruise-lines and holiday destinations run CodeGen's TravelBox software. With a 300
large employee base, based in Sri Lanka, UK, Canada and shortly in the U.S.A,
CodeGen is regarded as a leader in innovative software solutions provider.
Dr. Harsha Subasinghe is the co-founder and CEO of CodeGen International
Group of Companies. Dr. Subasinghe has a broad knowledge in various industries,
spanning computing, electronics, education, fashion and food, which he developed
through innovative Research and Development (R&D) at CodeGen International.
VEGA Technology is his idea.
Vega is a small team of highly motivated multi-disciplinary individuals pushing
the boundaries of technology. The teams includes engineers in Electrical, Electronics,
Figure 1.1: Company Logo
Figure 1.2: VEGA Technology’s Logo
10 | P a g e
Mechanical, Material, Software, Design, Project Management and Business
Administration fields.
Main target of the VEGA Technology is making a supper electric car. And also
they are making three type of electric car chargers and doing some small projects. In
this role Dr. Beshan Kulapala is leading CodeGen's efforts to expand in to electronic
and mechatronic product development. Dr. Beshan is a Research Scientist at CodeGen
International, Sri Lanka.
Contact details of CodeGen (Pvt) Ltd:
Address : Bay 1-5, Tripoli Square, Maradana
Telephone : +44 (0)20 8223 7481 or +94 112 470 740
Website : www.codegen.net
Contact details of VEGA Technology:
Address : Vega Technologies Pvt (Ltd). Trace Expert City,
Tripoli Market, Maradana, Sri Lanka.
Telephone : +94-1-5551-551
Website : info@vega.lk
1.1.2 Vision.
To be known globally for first mover end-to-end ICT solutions.
1.1.3 Mission.
Crafting high quality, intelligent ICT solutions by a community of dynamic
professionals through continuous research and knowledge sharing to optimize
business processes of corporate enterprises.
11 | P a g e
1.1.4 History.
Innovation has always being the nucleus for CodeGen, a multi-national
software company, founded in 1999 by Dr. Harsha Subasinghe, Mr. Bharat Patel and
Mr. Kusal Subasinghe. It is known to be one of the pioneers in using Open Source
Systems, Artificial Intelligence and it has ventured in to other business investments
such as Electronics, Medical Electronics and Automobile developments in Sri
Lanka.
CodeGen Sales and Marketing division was established in 2001 under the name
CodeGen Ltd at London United Kingdom. Having BOI status in 2001, CodeGen
successfully entered to the international market being a proud Sri Lankan product.
By introducing the “TravelBox Technology” to the world of tourism they
released their core software product “TravelBox” in 2003. It was a solution provider to
leading travel operators, air lines, tour consolidators, hoteliers and many other travel
oriented companies around the globe. AirTransat, Quantas, Virgin Holidays and Saga
Holidays are currently major giant clients of Travel box. Though CodeGen is product
base software firm it is working with other many bespoke software productions as well.
In 2014 CodeGen was moved to a newly established Trace City situated in
previously known place as “Tripoli Market”. Then 2014, Company started Sri Lanka’s
first ever car production process, VEGA an electric super car, as a research and
development entity under CodeGen.
1.1.5 Awards.
As their main product “TavelBox” Generates the most of the revenue for the
company. Since 2003 first sale of the product many companies in travel and
tourism industry have trusted CodeGen by TravelBox. Among the clients of
TravelBox “Virgin Holidays” the largest tour operator in United Kingdom, the 4th
largest in the world, and most successful transatlantic tour operator and the market
leader for travel to the USA and Caribbean completely operates on TravelBox
software. TravelBox generates over 400 million euros in profit per year.
12 | P a g e
Most recently one of the World largest travel company “Disney” join to the client list
of the CodeGen. Other than TravelBox, Zoom Sri Lanka has a lot of potential to
dominate the travel and tourism industry in Sri Lanka. It is generate revenue from
local travel and tourism industry.
In addition to those products CodeGen carry the VEGA project that touch automation
industry by manufacturing Electric Vehicles. As a part of this project they generate
income by producing electric vehicle chargers. At the moments they produce three
versions of chargers and hope to go for the mass production.
As a company CodeGen won following awards;
Technology Team of the Year - Travolution Awards-2015
Outstanding Entrepreneur - APEA Awards 2014
Gold Winner - Tourism and Hospitality Category - NBQSA Awards 2013
Bonze Winner - Overall Category - NBQSA Awards 2013
1.2 Organization Structure.
1.2.1 Organization Structure of CodeGen (Pvt) Ltd.
The board of directors consists with three founders of the CodeGen Dr. Harsha
Subasinghe, Mr. Bharat Patel and Mr. Kusal Subasinghe. They form an ideal mix of
skills and professional backgrounds.
Dr. Harsha Subasinghe (CEO & Chief System Architect)
Dr. Harsha has many years of experience in software environment who having
previously worked as a software engineer and project manager. Also he has PhD
in development of intelligent agents. He is the responsible person for overall
management and software development process as the development director. He
shares his knowledge and experience with team members in development or designing
new projects.
13 | P a g e
Mr. Bharat Patel (Commercial Director)
Mr. Barat Patel was being Managing Director of a large travel agency and tour operator
who has many years of experiences in the development of travel-related software. He
is a valuable resource for CodeGen in the area of the business as well as leading the
company’s Sales & Marketing activities. Also Mr. Barat holds a directorship in a
specialist travel software house.
Mr. Kusal Subasinghe
Mr. Kusal is the person who responsible for all the legal documentation and
input that is involved in the development and delivery of the company's software
solutions and day-to-day operational and financial management of CodeGen in Sri
Lanka. Mr. Kusal is a well-recognized experienced corporate lawyer and legal
consultant. Also he is the founder of a very famous law firm and investment brokerage
in Colombo.
In addition to the board of directors Company consist with following hierarchy.
Figure 1.3: CodeGen Hierarchy
14 | P a g e
1.2.2 Organization Structure of VEGA Team.
It’s an absolute technological miracle form this miracle island. Experts from
Electrical, Electronics, Mechanical, and Material Science background in private sector
as well as government sector come together to develop this complex engineering
project. Currently there more than 20 staff including 8 full time staff, volunteers and
trainees.
VEGA Team leader, Dr. Beshan Kulapala is leading CodeGen's efforts to
expand in to electronic and mechatronic product development. Dr. Beshan is a Research
Scientist at CodeGen International, Sri Lanka. Electronic & Telecommunication
Engineer Mr. Pabasara Karunanayake is VEGA project manager. Two Electrical
Engineers, one System Engineer, two Mechanical Engineers and one Material Engineer
are working for VEGA project as full time staff.
Figure 1.4: Organization structure of the VEGA team
15 | P a g e
1.2.3 Working culture and people
In CodeGen there is very cool and clam working culture. They maintain flat
hierarchy among employees and no more pushes or forced power for employees. For
new comers, it’s very easy to mix with every one and adapt to the situation. Also
CodeGen never discriminate employees due to gender, race, nationality, color or
religion. There is no separation other than responsibilities. Employees can address
their work related problems effectively and discuss until it solved. Company believes
that any matter can be solved by working together. This is called as “Open Door
Policy”.
Employees has very flexible time frame to work in CodeGen. Usually working hours
are 8.30 am – 5.30 pm but there is no any restriction so employees can choose their own
arrival and leaving time as they cover their work.
People in the CodeGen are very friendly and humble. They help interns in
technological matters as well as day to day life situations.
Employees can join with many events, functions which are organized by
many clubs and societies. CodeGen pool championship, annual trip, annual
bowling tournament, New Year festival, cinema shows, Dharma Deshana, Birthday
celebration are some of them. Also employees can join with those societies and clubs
as they wish. Welfare society, Photography club and Toastmasters club are the popular
among them. Also a pool table, a carom board, a table tennis court and a fully
equipped music band is provided by the company in order to maintain low stress
levels of the employees. Also Health Insurance Scheme, Staff Transport,
Reimbursements, Club Membership, Recreation are provided by the company
1.2.4 Company values
No one is left aside
CodeGen always encourage employees and try to get 100% out of them. Also each and
every project is a team work. A team consists of a Project Manager, a Tech Lead,
Senior Software Engineers, Software Engineers and QA Engineers.
16 | P a g e
Freedom and Creativity
They welcome any idea, comments or claims from any person in the project. Also they
give the freedom to think as they wish and come up with innovative and creative ideas.
The project manager or the software architect doesn't insist on a change unless it is
absolutely necessary.
Self-discipline
All employees are expected to have good qualities and they do. So no one is going to
make issues with others and no one is going to tell someone to how to behave. They
believe all are well educated and respected.
Responsibility
Each team member has to take sets of responsibilities as the role he/she plays in that
team. They have to complete their own responsibilities on or before given deadline.
Respecting Ideas
CodeGen always respect ideas of anyone. So anyone can come up with any idea and
it’s open to discuss.
Passion for futuristic developments
There is no completion of a project. Continuous developments are encouraged.
1.2.5 Products and services of CodeGen International (Pvt) Ltd.
The different products in CodeGen cover variety of business areas in all over the
world. Also those products are second to none of the existing products in the
world market. CodeGen involves in world business in threefold by basically focusing
travel industry and banking and gaming as their second interests. We can list their major
products as follows.
17 | P a g e
1. TravelBox
TravelBox is the main product developed by CodeGen, today it is the result of
more than 15 years of experience and evolution of CodeGen work. TravelBox
Technology is a revolutionary, next-generation Web Services-based platform that
forms the foundation of a suite of advanced software solutions designed specifically
for the travel and tourism industry. It can assist the company in a vast range of
operations including availability searching, bookings, inventory management,
costing, pricing, documentation, communication and accounting. TravelBox
Technology is an end-toend solution and it can help in all areas the business,
from pre-sales right through to accounting. This solution minimizes the many
manual works in Travel and Tourism industry.
2. Ru-Bank
Ru-Bank is a product that CodeGen involves with banking industry in Sri Lanka.
Ru-Bank has developed by CodeGen after a deep research in challengers faced
by co-operative bank community in Sri Lanka. Ru-Bank is a solution package
for small bankers who need to computerize their core business processes. Ru-
Bank has been developed to computerize the front and back office activities at
an affordable price. The enhanced version includes in addition, the ability to manage
all head office activities, produce customer documentation in more than one language,
and to manage the synchronization and archiving of customer data across a branch
network. Ru-Bank is used by more than 12 banks in Sri Lanka.
Figure 1.5: TravelBox Product Banner
Figure 1.6: Ru-Bank Logo
18 | P a g e
3. Destination Management System
With this solution CodeGen promote local business such like hotels, events,
restaurant and etc. to outside world. It consist with three main systems Content
Management System (CMS), Product Management System, Geographical Information
System (GIS).
4. Zoom Sri Lanka
Zoom Sri Lanka is a web application that enables travelers to plan their vacation in
Sri Lanka by considering geographical region. Travelers in entire world can search on
Sri Lanka map and get details under categories like culture, beach, nature, regions,
cities and etc. Also it includes Zoom Magazine, Hotel booking chapter, Restaurant
chapter, and Activities chapter.
5. Savaree
Savaree is almost an extension of TravelBox that facilitate to search for
accommodations and other holiday items under capability of Artificial Intelligence. It
can provide more relevant and updated search results to the user.
Figure 1.7: Destination Management Product Banner
Figure 1.8: Zoom Sri Lanka Logo
Figure 1.9: Savaree Banner
19 | P a g e
6. Global Online Poker Playing
This is the product that CodeGen involves with gaming. With this solution players
in the world can play poker against other players online using a downloadable plug-in.
Players has their own accounts and money can be debited or credited to accounts by
using credit cards.
7. Bespoke Development
In addition to the above products CodeGen developed many bespoke projects
for different customers. Automation of Customer Service Centre of Sri Lanka Ports
Authority is one of the most prominent bespoke projects and it handles to whole
container handling process of the ports.
8. Electric Vehicle Chargers
Electric Vehicle Chargers is the most recent product of the company. Those
chargers are produced by the VEGA Team. This was started as a R&D project and now
it’s ready to be sold in open market. There are two version of Chargers Called
“Level 2” and “Super Charger”. As the Electric vehicle market increased during the
last session these product has more demand in the society. Also these chargers are
well design for local conditions and integrated with multi payment gateways which
are already available in Sri Lanka.
Apart from those products CodeGen provides services to their products as well,
Customization of the products based on user requirements
Upgrading and customizing the sold software
Maintaining the sold software
Provide training to use the sold software
9. Vega vex project
VEGA EVX is the most recent grand investment of CodeGen. CodeGen initiated
this project with “Trace” to locally develop and manufacture Sri Lanka’s first high
performance electric sport car. Top speed of 240kmph, a 240km range, and 0-
100kmph acceleration under 4 seconds are the key aspects that team VEGA hope to
reach once they complete the car.
20 | P a g e
1.2.6 Strengths.
As a product based Software Company CodeGen has several strengths that move
them towards to the well-recognized and sustained company.
First thing is the experience and the domain knowledge that they gain from last
15 years from the travel and tourism industry. With the product of TravelBox
they have done so many researches and understand the challenges of the
industry.
The brand reputation that they have gained through TravelBox is one of
the strengths CodeGen has. Also they have world class clients. So many
companies tend to buy TravelBox.
As the CEO Dr. Harsha Subasinghe hold PhD in Artificial Intelligence that
influence and shares knowledge with the R&D teams, So CodeGen has number
of ongoing and successfully 13 one research and development projects related
to artificial intelligence. This makes software to be more users friendly.
Flat hierarchy and user friendly working environment motivate the staff
of the CodeGen to give their best to the company.
Attractive salary scheme of the company draw fully skilled employees.
Figure 1.10: The SolidWorks model of the car designed by VEGA
21 | P a g e
1.2.7 Weaknesses.
As CodeGen is a product based company if someone attracted to the industry
they will lost all the revenue. So they have to work hard and think hard about
the future of their products.
There are few weaknesses as I identified during my internship most of them are related
with VEGA project.
Lack of permanent Electrical and electronic Engineers is another concern. Due
to this the workload that one person has too many. So it reduces the
effectiveness and quality of the work. Also when it comes to the complex
designs, takes more times and lot of components to clarify the correct procedure.
So if they can get another two three experienced engineers it would be
much easy to carry out the proceedings.
Then lack of instruments and testing equipment is another problem. As a result
of it sometimes we have to wait many hours to test the product. As a R&D
project testing and verification is main concern. But many times we have to
share instruments and equipment with others due to limited resources.
Also PCB fabricating issues are another problem. As there is no any proper way
to fabricate in here, have to outsource from china. So it takes much time.
1.2.8 Suggestions to overcome Weaknesses.
To improve much more they need to avoid weaknesses. Also they have to think
new areas and new methods of software development rather going product
based solutions.
Considering electrical vehicle industry if they can quickly move to domestic
vehicles such as Cars, replacement for three wheelers, etc. they can grab the
local market. Also they need to increase the engineering staff in VEGA project.
22 | P a g e
In addition to that if CodeGen can move to the Robotics and Bio-Medical
industries which are current trend of the world, they can catch the most of the
world market as they are well known company.
1.2.9 Opportunities.
As CodeGen is a well-recognized and experienced software company in the travel and
tourism industry, through TravelBox CodeGen has many opportunities. If they can
precede their agreements with “Disney”, it’s a huge achievement. Also extend of the
TravelBox that include with Artificial Intelligence grab more clients.
When we consider about the VEGA project it’s really open market for Electrical
vehicle industry. As there is less number of electrical vehicle productions company in
the world and only company in Sri Lanka VEGA can be marketed in locally as well as
globally. So it’s a real opportunity to generate revenue.
Then as the increment of the Electrical vehicles in Sri Lanka, Electrical vehicle chargers
are highly demanded. So VEGA team also produces chargers it will earn considerable
amount of revenue through chargers. Also those chargers are totally made in Sri Lanka
with facilities that suitable for local market make an extra opportunity.
1.2.10 Threats
One threat that CodeGen has is their product based software development. If the travel
and tourism industry change strategies or get lost CodeGen also lost almost their
revenue.
Then considering the electric vehicle industry, there are well known automobile
companies who engaged with electric vehicle industry. Tesla, Nissan, Mitsubishi
are some companies already engaged with the industry. So it’s threat for VEGA in
world market. As VEGA is super car it’s a threat in local market.
Cheap electrical vehicle chargers are another threat. Due to that situation investors
tends to buy those products rather than Local products.
23 | P a g e
Chapter Two
Technical Details.
2.1 Introduction to VEGA Project.
VEGA is Sri Lanka’s ambition initiative to develop and manufacture a world
class high performance electric sports car. Once completed, the car will reach 0 to 100
kmph under 4 seconds, a 240 km range, and a top speed of 240 kmph. It will join a
small list of high performance cars in the world, and be an absolute technological
marvel for all of Sri Lanka.
Been developed through a consortium of expert in the private sector and
government universities, this project encompasses a large set of Sri Lankan experts
from all over the world. VEGA wants to build a unique culture in Sri Lanka where
experts from different areas can be brought together readily, and then be tasked to
handle complex engineering projects to success.
With the dawn of the electrical vehicle era, expertise for vehicle development
has focused on electronics, software, battery and motor technology. With world class
experts in Electronics and Electrical engineers in Sri Lanka, we are uniquely positioned
to take advantage and take the lead on electric vehicle and electric vehicle component
development. Before, combustion engines required a focus on mechanical engineering,
tooling, iron casting and other technologies that Sri Lanka was not focused on. But with
electric vehicles all that has changed, the focus on electronics and software is where we
shine.
Figure 2.1: Final design of the VEGA car
24 | P a g e
Looking on the technical of VEGA, this beast is powered by a 330V and
40kWh LiFePO4 battery pack with an active cooling system. The total discharge
current in peak performance is 1200A. The two rear wheels are independently driven
by Permanent Magnet Synchronous Motor (PMSM) each with 450bhp. There is no
mechanical differential to distribute the power to two wheels. Both wheels are
independently controlled with an electronic differential in order to achieve more
stability and traction. The chassis is designed with a space frame structure in order to
achieve the rigidity and safety. The body panels are made out of carbon fiber since high
strength to weight ratio is really important for the light weight. The total weight of the
car will be around 1600kg. The body design is optimized through aero dynamic
simulations to achieve sleek design as well as top speed.
There are enormous benefit to reap from building an electric vehicle industry
in Sri Lanka. First the multi-disciplinary aspect of the industry will create job
opportunities for a wide variety of Sri Lankan student graduates. It will spawn interests
in new research and curriculum, bring a renewed value to our technology education
hub. Having the technology to convert existing combustion engine vehicles to electric
cars will have potential to save US $2.5 billion in fuel imports. By converting to electric,
we will eliminate toxic environment pollution, and be able to provide a safe
environment for our generations to come. Once the technology is mastered, we will be
Figure 2.2: Motor controller design of VEGA car
Figure 2.3: Battery pack design of VEGA car
25 | P a g e
capable of developing other electric vehicles from mass transport, to 3 wheeled people
movers. Having a world class vehicle manufacturing capability in Sri Lanka, we will
save billions of dollars per year on foreign vehicle imports to the country.
As a project, VEGA is not only making an electric car. VEGA team does some
sub project with the university undergraduates. Some completed sub projects are
mentioned bellow.
Electric vehicle chargers.
ChargeNET.
Domestic off peak energy storage system.
RFID base school attendance system.
Finding mathematical algorithm for quad copter balancing.
Electric vehicle chargers and ChargeNET are only profitable production of the
VEGA. Commercially they product three type of electric chargers as Level One (Home
chargers), Level Two and Level Three (Supper charger).
Figure 2.4: Level One charger
Figure 2.5: Level Two charger
Figure 2.6: Level Three charger
26 | P a g e
ChargeNET is a network of the all the VEGA’s eStation. Using ChargeNET
website or mobile app any user can see what are the nearest eStation are and what are
the available at that movement. ChargeNET android, Windows and iso mobile apps are
now available.
If anyone have ChargeNET membership, they are issued a membership card.
Members can go to any bank and deposit money to the ChargeNET account. After that
member should call or send an email to ChargeNET, and then they will update
member’s account with the deposited amount. Members can also deposit money
through dialog EZcash, Mobitel mCash or pay at ChargeNET office in Tripoli Market
Maradana. Now, members can have self-service from eStation by tapping membership
card. No need to keep cash, pay at a cashier or wait for someone to come turn on the
system.
2.2 Introduction Electric vehicles (EV) and inside of an EV.
In a conventional car, the energy is stored in chemical form, locked inside the
gas you've pumped in your tank; you release it through a chemical reaction happening
inside the engine in which the hydrocarbon molecules in gasoline burn with oxygen in
the air to release heat, which pushes the pistons that turn the wheels (this all happens
inside the engine's cylinders, so we call it internal combustion).
Electric cars also use stored chemical energy, though they release it
electrochemically, without any kind of combustion, as electrons ping from their slowly
discharging batteries; there's no burning of fuel, no air pollution spewing from the
tailpipe, and no emissions of any kind are produced by the car itself.
Figure 2.7: ChargeNET membership card
27 | P a g e
The main part of an electric car is mentioned in below;
1 Electric Motor
2 Inverter
3 Main Battery
4 Battery Management system (BMS)
5 Charger
6 Reduction Drive
7 High Voltage Circuit
8 Accessories Battery
9 Relay
10 Microcontrollers
Electric motor and Main Battery are the main part of an electric car. In the
electric car manufacturing AC motors are used than the DC motors, because the
advantages of the AC motors (DC motors are constructed with brushes and a
commutator, which add to the maintenance, limit the speed and usually reduce the life
expectancy of DC motors). There are two type of AC motors as Induction Motor and
Permanent Magnet Synchronous Motor (PMSM). VEGA team uses two Permanent
Magnet Synchronous Motor with Reduction gear box that it was designed by VEGA
mechanical staff.
Motor controller is a very important part of an electric car. It control the high
voltage power supply using low voltage signals to drive electric motors of the car.
Normally motor controller consist inverter, bus bars, voltage sensors, current sensors,
Figure 2.8: The image of a permanent magnet synchronous motor that is used by
electric cars
28 | P a g e
temperature sensors, snubber circuits and microcontroller. When the car is accelerated,
generated analog signal convert to PWM signal using a microcontroller. Then that
PWM inputs are supplied to another microcontroller in the motor controller. That
microcontroller is supplied all the voltage, current, temperature sensor outputs, gate
driver fault signal and motor resolver. By checking all the input signals, second
microcontroller supplies PWM signal to the gate drivers. There are two motor
controllers are consist in VEGA car to drive two electric motors independently.
Inverter can be changed according to the motor type. VEGA uses DC-AC
inverter with Texas microcontrollers. VEGA DC-AC inverter was designed using six
POWEREX or IXYS IGBTs (insulated-gate bipolar transistor).
Figure 2.10: The image of an IGBT that is use by VEGA
Figure 2.9: Two motor controllers of VEGA car
29 | P a g e
Inverter is powered by 330v and U, V & W terminals were connected to the
three terminals of the PMSM. Six gate signals comes to the IGBTs’ gate through the
gate drivers. Driving motors of the electric car is a closed loop system. For that motor
exist a resolver. The resolver provides extremely accurate position information to the
inverter via the low voltage connection. The resolver receives field coil excitation from,
and returns sensor coil signals to the inverter to provide precision rotor position
information for accurate synchronization of the signals supplied by the inverter.
Main battery and the Battery Management System of an electric car are also
very important parts. Vega's LiFePO4 battery modules are designed for automotive as
well as for stationary industrial or consumer use.
Battery Management System (BMS) plays a critical role in ensuring durability,
and safety of the battery pack. VEGA advance BMS software runs on multiple micro-
controllers in each of the battery modules. For multi battery module management, a
supervisory level BMS solution is implemented. This BMS supervisor managers
multiple battery packs, takes intelligent actions based on faults and errors, and reports
and accepts command from upper level software for completely flexibility.
Figure 2.11: DC-AC inverter using six IGBTs
30 | P a g e
2.3 Introduction to my training experience.
As my second industrial training I was assigned to CodeGen
International Pvt. Ltd., VEGA project that under goes with design and manufacturing
of first Electric super car in Sri Lanka. In addition to the Electric super car they produce
Electrical vehicle chargers as well. In the three months period of my training I
gained lot of technical and non-technical experiences through the VEGA project. In
my training period I directly involved with motor controller designing & development
team. As a trainee, I have done following things with VEGA team.
Motor driver was developed using VLA500-01 hybrid integrated gate driver.
Motor driver was re-designed using VLA503-01 hybrid integrated gate driver
and VLA106-15242 hybrid integrated DC-DC power supply.
The gate resistor board was designed according to driver board dimension.
Collected information about isolation amplifiers and create a document about
ACPL-782T and ACPL-C87B isolation operational amplifiers.
Temperature, voltage and current sensors were simulated using TINA-TI.
Participated for PCBs fabrication using UV light.
Participated for the new gate driver experimentations and debugging. This gate
driver was created by using TOSHIBA TLP5214 isolation amplifier.
2.3.1 PCB designing.
A printed circuit board (PCB) mechanically supports and electrically connects
electronic components using conductive tracks, pads and other features etched from
copper sheets laminated onto a non-conductive substrate. Components - capacitors,
resistors or active devices - are generally soldered on the PCB. Advanced PCBs may
contain components embedded in the substrate.
PCBs can be single sided (one copper layer), double sided (two copper layers)
or multi-layer (outer and inner layers). Conductors on different layers are connected
with vias. Multi-layer PCBs allow for much higher component density.
There are numerous software packages available for designing printed circuit
boards (PCBs), too many in fact. That being said, there are three PCB design packages
31 | P a g e
that are the most popular: Altium, Eagle, and OrCAD. Among them, VEGA uses Eagle
cad software to design PCBs. Then designed PCBs are checked using GerberLogix
software before send them to fabrication.
What is eagle?
EAGLE, the Easy Applicable Graphical Layout Editor is a powerful PCB
design software tailored to meet the needs of professional engineers, makers and those
at school. The simplicity of the software provides a fast learning curve, even for those
new to PCB design. The openness of EAGLE design resources, such as its extensive
and fully-open component libraries, ease the design process for all.
EAGLE includes the following modules:
Schematic Editor
The schematic editor allows users to create a symbolic easy-to-read representation of
their design. The goal of the schematic is to provide documentation about the design,
allowing others to easily understand users’ design intent. EAGLE comes with
thousands of pre-made parts that simplify users’ schematic capture tasks. The ERC
functionality checks that users have defined all of their connections properly.
Layout Editor
The layout editor brings users’ design to life. The board represents the physical reality
of users’ design. Users can locate their components accurately and route copper traces
between them. EAGLE's Layout editor includes sophisticated features such as assembly
variants, differential pair routing and much more
Autorouter
The autorouter is a useful tool for placing copper traces between components. The
autorouter can be guided by adjusting its cost factors to control its routing behavior
producing useful results in no time. The autorouter runs as a multi-threaded application,
so users can explore several routing variations to choose the best option for your design.
The Autorouter protects pre-routed traces giving you full control over what nets need
to be manually routed and which can be routed automatically.
32 | P a g e
Library editor optimization
Now user can create their own library or develop a library using eagle library editor
with lot of options.
Ex: Connect a pin to multiple pads.
Draw arbitrary pad shapes easily.
What is GerberLogix?
It’s always a good idea to review PCB gerber files before committing
them to the PCB fabrication house. We review the gerber for any problems that might
have happened in the export process. It’s not an in-depth check that happens in the CAD
program, this is just a quick verification of following mistakes in PCB layout.
Missing solder pads – problems with the footprint, the solder pad is sometime
buried by mask
Drill problems – drills outside board or flipped
Silk problems – CAM didn’t export expected silkscreen layers
2.3.2 Motor driver board was designed using VLA500-01 gate-driver
This is a fully isolated two channel gate-drive circuit designed for use with dual
IGBT modules. The designed driver board utilizes Powerex VLA500-01 hybrid gate
drivers to provide efficient switching of modules rated up to 1400A. The hybrid gate-
drivers also provide protection against unexpected short circuit conditions using
desaturation detection. The VLA500-01 hybrid gate-drivers have an integrated DC to
DC converter with 2500VRMS isolation to provide isolated gate drive power. Control
signals are isolated using high speed opto-couplers with 15kV/µs common mode noise
immunity. This motor driver board provides an isolated fault feedback signal if a short
circuit condition is detected. Features of this driver board:
Up to 12A Peak Output Current
2500VRMS isolation for control power and signals
Operates from a single 15VDC supply
Wide output voltage swing +15V/-8V
33 | P a g e
VLA500-01 hybrid integrated gate driver
The VLA500-01 is a hybrid integrated circuit designed to provide gate drive for
high power IGBT modules. This circuit has been optimized for use with Powerex NF
Series and A-Series IGBT modules. However, the output characteristics are compatible
with most MOS gated power devices. The VLA500-01 features a compact single-in-
line package design. The upright mounting minimizes required printed circuit board
space to allow efficient and flexible layout. The VLA500-01 converts logic level
control signals into fully isolated +15V/-8V gate drive with up to12A of peak drive
current. Isolated drive power is provided by a built in DC-to-DC converter and control
signal isolation is provided by an integrated high speed opto-coupler. Short circuit
protection is provided by means of desaturation detection.
Figure 2.12: Designed schematic of VLA500-01 gate driver using eagle library
editor
Figure 2.13: Designed package of VLA500-01 gate driver using eagle library
editor
34 | P a g e
Fig
ure
2.1
4:
Sin
gle
sid
e sc
hem
ati
c of
the
du
al
mod
e gate
dri
ver
board
usi
ng V
LA
50
0-0
1 g
ate
driv
er
35 | P a g e
Short Circuit Protection
Figure 14 shows a block diagram of a typical desaturation detector. In this
circuit, two high voltage fast recovery diodes (D1 & D2) is connected to the IGBT’s
collector to monitor the collector to emitter voltage. When the IGBT is in the off state,
VCE is high and D1 & D2 are reverse biased. With D1 & D2 off the (+) input of the
comparator is pulled up to the positive gate drive power supply (V+) which is normally
+15V. When the IGBT turns on, the comparators (+) input is pulled down by D1 & D2
to the IGBT’s VCE(sat). The (-) input of the comparator is supplied with a fixed voltage
(Vtrip). During a normal on-state condition the comparator’s (+) input will be less than
Vtrip and it’s output will be low. During a normal off-state condition the comparator’s
(+) input will be larger than Vtrip and it’s output will be high. If the IGBT turns on into
a short circuit, the high current will cause the IGBT’s collector-emitter voltage to rise
above Vtrip even though the gate of the IGBT is being driven on. This abnormal
presence of high VCE when the IGBT is supposed to be on is often called desaturation.
Desaturation can be detected by a logical AND of the driver’s input signal and
the comparator output. When the output of the AND goes high a short circuit is
indicated. The output of the AND can be used to command the IGBT to shut down in
order to protect it from the short circuit. A delay (ttrip) must be provided after the
comparator output to allow for the normal turn on time of the IGBT. The ttrip delay is
set so that the IGBT's VCE has enough time to fall below Vtrip during normal turn on
switching. If ttrip is set too short, erroneous desaturation detection will occur. The
maximum allowable ttrip delay is limited by the IGBT’s short circuit withstanding
capability. In typical applications using Powerex IGBT modules the recommended limit
is 10µs. `
Figure 2.15: Single side PCB layout of the dual mode gate driver board
using VLA500-01 gate driver
36 | P a g e
Operation of the VLA500-01 Desaturation Detector
The Powerex VLA500-01 incorporates short circuit protection using
desaturation detection as described above. A flow chart for the logical operation of the
short circuit protection is shown in Figure 14. When a desaturation is detected the
hybrid gate driver performs a soft shutdown of the IGBT and starts a timed (ttimer)
1.5ms lock out. The soft turn-off helps to limit the transient voltage that may be
generated while interrupting the large short circuit current flowing in the IGBT. During
the lock out the driver pulls Pin 28 low to indicate the fault status. Normal operation of
the driver will resume after the lock-out time has expired and the control input signal
returns to its off state.
Adjustment of Trip Time
The VLA500-01 has a default short-circuit detection time delay (ttrip) of
approximately 3µs. This will prevent erroneous detection of short-circuit conditions as
long as the series gate resistance (RG) is near the minimum recommended value for the
module being used. The 3µs delay is appropriate for most applications so adjustment
will not be necessary. However, in some low frequency applications it may be desirable
to use a larger series gate resistor to slow the switching of the IGBT, reduce noise, and
limit turn-off transient voltages. When RG is increased, the switching delay time of the
IGBT will also increase. If the delay becomes long enough so that the voltage on the
detect Pin 30 is greater than VSC at the end of the ttrip delay the driver will erroneously
indicate that a short circuit has occurred. To avoid this condition the VLA500-01 has
provisions for extending the ttrip delay by connecting a capacitor (CT1) between Pin
29 and VEE (Pins 21 and 22). If ttrip is extended care must be exercised not to exceed
the short-circuit withstanding capability of the IGBT module. Normally this will be
satisfied for Powerex NF and A-Series IGBT modules as long as the total shut-down
time does not exceed 10µs.
Adjustment of Soft Shutdown Speed
As noted above the VLA500-01 provides a soft turn-off when a short circuit is
detected in order to help limit the transient voltage surge that occurs when large short
circuit currents are interrupted. The default shutdown speed will work for most
applications so adjustment is usually not necessary. In this case CS1 can be omitted. In
37 | P a g e
some applications using large modules or parallel connected devices it may be helpful
to make the shutdown even softer. This can be accomplished by connecting a capacitor
(CS1) at Pin 27.
2.3.3 Motor driver board was re-designed using VLA503-01 gate driver and VLA106-15242 DC-DC power supply.
This is a two channel gate drive circuit for high power IGBT modules. The
designed driver board utilizes Powerex hybrid gate drivers and DC to DC converters to
provide efficient switching of modules rated up to 400A. The hybrid gate drivers
include high speed opto-couplers for control signal isolation and desaturation detection
to protect the IGBT from short circuit conditions.
The hybrid DC to DC converters provide fully isolated control power for each
driving channel. This driver board also provides an isolated fault feedback signal.
Features of the driver board:
1.5A, 3A or 5A Peak Output Current
2500VRMS isolation for control power and signals
Operates from a single 15 VDC or 24 VDC supply
Wide output voltage swing +15V/-8V
VLA503-01 hybrid integrated gate driver
The VLA503-01 is a hybrid integrated circuit designed to provide gate drive for
high power IGBT modules. This circuit has been optimized for use with Powerex NF-
Series and A-Series IGBT modules. However, the output characteristics are compatible
with most MOS gated power devices. The VLA503-01 features a compact single-in-
line package design. The upright mounting minimizes required printed circuit board
space to allow efficient and flexible layout. The VLA503-01 converts logic level
control signals into fully isolated +15V/-8V gate drive with up to 5A of peak drive
current. Control signal isolation is provided by an integrated high speed opto-coupler.
Short circuit protection is provided by means of desaturation detection.
38 | P a g e
VLA106-15242 hybrid integrated DC-DC power supply
VLA106-15242 is a DC-DC converter. Its output power is 2.4W and the input is
isolated from the output. The over-current protection circuit is built-in. This device is
used for on-board power supplies in industrial control equipment.
Features:
Input Voltage Range: 12.0 to 18.0V DC
Figure 2.16: Image of VLA503-01 hybrid integrated gate driver
Figure 2.17: Designed schematic of VLA503-01 gate driver using eagle
library editor
Figure 2.18: Designed package of VLA503-01 gate driver using eagle
library editor
39 | P a g e
Output: +24V, 100mA (Output Power: 2.4W)
Thin Profile, Lightweight Design
Electrical Isolation Voltage between Input and Output: 2500 Vrms for 1 Minute
Built in Over-current Protection Circuit
Figure 2.19: Image of VLA106-15242 hybrid integrated DC-DC
power supply
Figure 2.20: Designed schematic of VLA106-15242 hybrid integrated DC-DC
power supply using eagle library editor
Figure 2.21: Designed package of VLA106-15242 hybrid integrated DC-DC
power supply using eagle library editor
40 | P a g e
Fig
ure
2.2
2:
Sin
gle
sid
e sc
hem
ati
c of
the
du
al
mod
e gate
dri
ver
board
usi
ng V
LA
503
-01 g
ate
driv
er
41 | P a g e
There are few difference between first gate driver and this gate driver. Main difference
is DC-DC inverter is integrated with VLA500-01 hybrid gate driver IC of the first gate
driver board. So working principle is same. But some features of the two gate drivers
are difference as mentioned above.
2.3.4 The gate resistor board was designed according to driver board dimension.
Gate resistor is most important part in the driver board. According to the IGBT
module we had to change gate resistor value. If gate resistor value is not match, IGBT
will desaturase. Then IGBT will heat and after it will blast. Old driver board were
damaged, because of gate resistor replacement. So that we desired to build gate resistor
part separately. Then I create the gate resistor board PCB design according to driver
board dimension. That board can be connect and disconnect without disordering and
soldering.
Figure 2.23: PCB layout of the dual mode gate driver board using
VLA503-01 gate driver
42 | P a g e
2.3.5 Collected information and created report about isolation amplifiers.
There are number of isolation op-amp manufactures. Avago, Agilent, Toshiba
& etc. In my document I talked about Avago HCPL series and Avago ACPL series. By
comparing all the isolation operational amplifiers, we could select suitable one for
temperature, voltage and current sensor of the VEGA car. Car is an automotive system
and it will face for hazardous situations. So selected op-amp should have possibility to
face that kind of scenarios.
According to gathered information ACPL isolation operational amplifiers are
more suitable for car temperature, voltage and current sensor than the HCPL isolation
operational amplifiers. Because operating temperature range is lower and gain tolerance
is higher in HCPL isolation operational amplifiers. From ACPL isolation operational
amplifiers ACPL-782T and ACPL-C87X are better than other ACPLs. Comparison
table of the ACPL-782T and ACPL-C87X is shown in below.
Figure 2.24: Gate resistor board
43 | P a g e
According to above comparison ACPL-782T and ACPL-C87B isolation
operational amplifiers are suitable for temperature, voltage and current sensing circuits.
Operating temperature range and gain of the ACPL-782T is higher than the ACPL-
C87X. But ACPL-C87X has large input voltage range compare with ACPL-782T. And
also we can have good gain tolerance using ACPL-C87X (Gain tolerance of ACPL-
C87B is -/+0.5%). Most important thing is active high shutdown pin of the ACPL-
C87X. Therefore using ACPL-C87B, we can have more accurate and safety
temperature, voltage and current sensor.
2.3.6 Designed and Simulated temperature, voltage and current sensors using TINA-TI.
I designed and simulate temperature, voltage and current sensors for ACPL-
C87B isolation operational amplifier using TINA-TI simulation software. TINA-TI is
a product of Texas instrument. If 𝑉𝐼𝑁 for the ACPL-C87B isolation operational
amplifier is equal to 2V, then 𝑉𝑂𝑈𝑇+ = 2.25V & 𝑉𝑂𝑈𝑇− = 0.25V or then 𝑉𝑂𝑈𝑇+
= 0.25V & 𝑉𝑂𝑈𝑇− = 2.25V according to following table. (ACPL-C87X isolation
operational amplifier is unity gain op-amp);
ACPL-782T ACPL-C87X
Operating temperature range is -40C to 125C
Operating temperature range is -40C to 105C
The gain is 8 Unity gain
Gain tolerance is + or - 2% Gain tolerance are + or - 3%(ACPL-C870), + or - 1%(ACPL-C870), + or – 0.5%(ACPL-C870)
Input voltage range is -200mV to 200mV
Input voltage range is -2V to 2V
There are 8 pin surface mount package and through hole package
Have only surface mount package. But it is stretched.
It doesn't have any shutdown pin. Have an active high shutdown pin.
Table 2.1: Comparison of ACPL-782T and ACPL-C87X
44 | P a g e
So if we consider 𝑉𝑂𝑈𝑇+ & 𝑉𝑂𝑈𝑇− are sinusoidal. Then the phase difference
between then 𝑉𝑂𝑈𝑇+ & 𝑉𝑂𝑈𝑇− is180°. If we use OPA350 op-amps we can create
voltage, current and temperature sensors as shown in below.
Voltage sensor using ACPL-C87B
According to the maximum value of measuring voltage, we have to select 𝑅′
and 𝑅′′. Those two resistors work like voltage dividers. 𝑅𝐴 and 𝑅𝐵 are also voltage
divider circuit. Those two resistors reduce the voltage level lower than maximum input
voltage of the isolation op-amp. The simulated voltage sensor schematic is shown in
below.
Figure 2.25: Output voltage vs Input voltage of ACPL-C87B
45 | P a g e
Fig
ure
2.2
6:
Volt
age
sen
sor
usi
ng A
CP
L-C
87B
iso
lati
on
am
pli
fier
an
d O
PA
350 o
pera
tion
al
am
pli
fier
.
46 | P a g e
If input signal voltage of the ACPL-C87B is change between maximum and
minimum values (-2V & +2V). Then output signal of the ACPL-C87B will change as
shown in below.
Considering first OPA350 op-amp;
Here 𝑅6 = 𝑅7 = 3.3k & 𝑅8 = 𝑅9 = 3.3k;
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 𝑅8
𝑅6 (𝑉𝐼𝑁+ - 𝑉𝐼𝑁−)
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 3.3𝑘
3.3𝑘 (4.5V – 0.25V)
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 4.25V
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 𝑅8
𝑅6 (𝑉𝐼𝑁+ - 𝑉𝐼𝑁−)
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 3.3𝑘
3.3𝑘 (4.5V – 2.25V)
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 2.25V
Figure 2.27: Input signal vs Output signal of the ACPL-C87B
47 | P a g e
Considering second OPA350 op-amp (This op-amp works as inverting buffer);
Considering third OPA350 op-amp;
Here 𝑅10 = 𝑅11 = 4k & 𝑅14 = 𝑅16 = 3.3k;
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 𝑅14
𝑅10 (𝑉𝐼𝑁+ - 𝑉𝐼𝑁−)
Figure 2.29: Vin(-) and inverted buffer amplified of Level shifted Vin(-)
using second op-amp
Figure 2.28: Vin(+) and Level shifted Vin(+) using first op-amp
48 | P a g e
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 3.3𝑘
4𝑘 (4.25V – 0.25V)
𝑉𝑜𝑢𝑡(𝑚𝑎𝑥) = 3.3V
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 𝑅14
𝑅10 (𝑉𝐼𝑁+ - 𝑉𝐼𝑁−)
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 3.3𝑘
3.3𝑘 (4.25V – 4.25V)
𝑉𝑜𝑢𝑡(𝑚𝑖𝑛) = 0V
Current sensor using ACPL- C87B
Simulated current sensor circuit is little bit difference from voltage sensor. In
here we have to replace 𝑅′ and 𝑅′′ resistors R(sense) resister that have small resistance.
Selected resistor should supply voltages for ACPL-782T op-amp between -200mV and
+200mV. Schematic diagram for current sensor using ACPL-782T is shown below. All
the calculation is same as voltage sensor calculation.
Figure 2.30: Level shifted output through third op-amp
49 | P a g e
Fig
ure
2.3
1:
Cu
rren
t se
nso
r u
sin
g A
CP
L-C
87
B i
sola
tion
am
pli
fier
an
d O
PA
350
op
era
tion
al
am
pli
fier
.
50 | P a g e
Temperature sensor using ACPL- C87B
Our thermistor’s (USP7765) operating temperature is between -40℃ to 105℃
and it gives 336,479 ohm for-40℃ and 587.6 ohm for 105℃. According to the following
circuit, isolated op-amp input signal is always positive. Therefore one differential op-
amp is enough for after isolation op-amp. (No need any voltage shifting like voltage
and current sensing)
Using 5V(ISO), we have to set input voltage between 0V - 2V. If input voltage is equal
to 2V, then output voltage can be found as shown in below.
Here 𝑅2 = 𝑅3= 2k & 𝑅4 = 𝑅5= 3.3k;
𝑉𝑂𝑈𝑇 = 𝑅4
𝑅2 (𝑉𝑂𝑈𝑇+ - 𝑉𝑂𝑈𝑇−)
𝑉𝑂𝑈𝑇 = 3.3𝑘
2𝑘 (2.25V – 0.25V)
𝑉𝑂𝑈𝑇 = 3.3V
Figure 2.32: Temperature sensor using ACPL-C87Bisolation amplifier and
OPA350 operational amplifier.
51 | P a g e
2.3.7 Participated for PCBs fabrication using UV light
At VEGA, I had good opportunity to participate PCB fabrication using UV
light. Normally commercial PCBs are sent china to fabricate by VEGA. But testing
BCBs are fabricated by themselves using above mentioned method. With the UV light
method it can be produced good single and double-sided PCBs for through-hole and
surface mount designs with track densities of 40-50 tracks per inch and 0.5mm SMD
pitches. Using following steps, a PCBs can be fabricate;
Getting the Layout Ready
In this step you will prepare your layout for etching. For this step you will need:
a quality laser printer, a sheet of transparent paper.
Exposing the Board
This step transfers your layout design to a positive-resist PCB by exposing UV
light to the sensitized PCB with the printout as a mask. For this step you will need: a
presensitized positive photoresist copper clad board, scissors, tape, a UV bulb and thin
plate glass or exposure unit. This step takes 5-10 minutes.
First, it should be turned off all the lights and used only red light source. Then
place the design on top of the exposed resist, ink-side down, so that it appears not-
mirrored when you look through the paper at the board. Placing the ink closest to the
resist means less light can leak around and cut into thin traces. Next, tape down the
design on two edges, so that the tape does not overlap any of the layout, but holds the
paper flat. Now take it to be exposed under a UV lamp.
Figure 2.33: A PCB layout that printed on transparent paper
52 | P a g e
After it has been exposed, peel off one piece of tape and flip it open, to look at
the photoresist. Well exposed photoresist is a paler green, and you will be able to see
the layout in the original, yellower green, faintly. If you don't see anything, re-tape that
side, and try a few more minutes under the lamp.
Figure 2.34: Removing sticker on the presensitized positive
photoresist copper clad board
Figure 2.35: UV bulb that used in VEGA
Figure 2.36: Exposing the Board using UV bulb at VEGA
53 | P a g e
Developing the Board
In this step, the exposed photoresist is removed chemically using developer,
leaving a positive of your layout in photoresist on copper. For this step you will need:
gloves, apron, sink, dev tray, developer, small soft sponge. This step takes 3 minutes.
Put on the apron and a pair of 'rubber gloves'. Find the dev tray and the bottle
of developer, (both marked DEV) and make sure the tray is clean. Place the board face
up in the tray and pour developer in until there is about 1/4" (or enough to cover) in the
tray. It should be developed in 1/2 to 1 minute. If you leave it in too long, some of the
finer traces won’t come out. Leaving it in too little means that there will be a very thin,
invisible, layer of resist left that will stop the etching process and force you to repeat
this step. Use a soft sponge to wipe the photoresist away.
Etching the Board
In this step, the board is placed in another tray, which is contain warm ferric
chloride (or another etchant) over the board, eating away any exposed copper. For this
step you will need to make sure the etchant is warm enough to use. This step takes
2minutes.
Figure 2.37: positive developer
54 | P a g e
Strip
In this step, the remaining photoresist is stripped away, leaving only copper. For
this step you will need chemical stripper and/or a scrub pad. This step takes 2 minutes.
Drilling
In this step, any holes or vias in the PCB are drilled out. For this step you will
need: a drill press that can run at 2000+ RPM, high-speed carbide wire-gauge drill bits.
This step takes 3-10 minutes, depending on number of holes in PCB.
Figure 2.38: Liquid ferric chloride
Figure 2.39: PCB drilling
55 | P a g e
2.3.8 Participated for the new gate driver experimentations and debugging
VEGA team did some experiments using another motor driver. This motor
driver was designed using TOSHIBA Smart Gate Driver Coupler TLP5214. I had
opportunity to participate, for that experimentation and debugging as my final work.
We got lot of experiments using oscilloscope, digital logic analyzer and
multi-meter. Sometimes I had to change gate resistor value. Sometimes I had to replace
the IGBTs, diodes and etc. While the experiments gate driver circuits were damaged.
Then I had to find the error and rebuild the circuit.
Figure 2.40: A new gate driver board using TOSHIBA
TLP5214 gate driver
Figure 2.41: A new gate driver experimentation
56 | P a g e
2.4 Why electric vehicles are popular in the present
An electric car is an automobile that is propelled by one or more electric motors,
using electrical energy stored in rechargeable batteries or another energy storage
device. Electric motors give electric cars instant torque, creating strong and smooth
acceleration. They are also around three times as efficient as cars with an internal
combustion engine.
The first electric cars were produced in the 1880s. Electric cars were popular in
the late 19th century and early 20th century, until advances in internal combustion
engines, electric starters in particular, and mass production of cheaper gasoline vehicles
led to a decline in the use of electric drive vehicles. The energy crises of the 1970s and
1980s brought a short-lived interest in electric cars; although, those cars did not reach
the mass marketing stage, as is the case in the 21st century. Since 2008, a renaissance
in electric vehicle manufacturing has occurred due to advances in batteries and energy
management, concerns about increasing oil prices, and the need to reduce greenhouse
gas emissions. Several national and local governments have established tax credits,
subsidies, and other incentives to promote the introduction and adoption in the mass
market of new electric vehicles depending on battery size and their all-electric range.
There are 15 Electric Cars Hitting the Market in 2015;
1 Tesla Model X
2 BMW X5 eDrive
3 VW Passat GTE Plug-in
4 Audi A3 e-Tron
5 Audi Q7 Plug-in
6 Rimac Concept_One
7 2016 Chevy Volt
8 Volvo XC90 T8
9 Mercedes-Benz GLE-Class Plug-in
10 Mercedes-Benz E-Class Plug-in
11 Mercedes-Benz C-Class Plug-in
12 Mitsubishi Outlander Plug-in
13 BYD Tang
14 Volvo S60 Plug-In
15 BMW 3 Series Plug-in
57 | P a g e
2.5 Advantages of EV
Saving money and no need petroleum fuels: These cars can be fuelled (Charging
batteries) for very cheap prices and a great way to save money in our own life.
No Emissions: Electric cars are 100 percent eco-friendly as they run on
electrically powered engines. It does not emit toxic gases or smoke in the
environment as it runs on clean energy source. They are even better than hybrid
cars as hybrids running on gas produce emissions.
Safe to Drive: Electric cars undergo same fitness and testing procedures test as
other fuel powered cars. In case an accident occurs, one can expect airbags to
open up and electricity supply to cut from battery. This can prevent you and
other passengers in the car from serious injuries.
Cost Effective: Earlier, owing an electric car would cost a bomb. But with more
technological advancements, both cost and maintenance have gone down. The
mass production of batteries and available tax incentives have further brought
down the cost, thus, making it much more cost effective.
Low Maintenance: Electric cars runs on electrically powered engines and hence
there is no need to lubricate the engines. Other expensive engine work is a thing
of past. Therefore, the maintenance cost of these cars has come down.
Reduced Noise Pollution: Electric cars put curb on noise pollution as they are
much quieter. Electric motors are capable of providing smooth drive with higher
acceleration over longer distances.
2.6 Disadvantages of EV
Recharge Points: Electric fuelling stations are still in the development stages.
So less number of charging points are available.
58 | P a g e
Short Driving Range and Speed: Most of these cars have range about 50-100
miles and need to be recharged again.
Longer Recharge Time: While it takes couple of minutes to fuel your gasoline
powered car, an electric car take about 4-6 hours to get fully charged.
Silence as Disadvantage: Silence can be a bit disadvantage as people like to hear
noise if they are coming from behind them. An electric car is however silent and
can lead to accidents in some cases.
Battery Replacement: Depending on the type and usage of battery, batteries of
almost all electric cars are required to be changed every 3-10 years.
Not Suitable for Cities Facing Shortage of Power: As electric cars need power
to charge up, cities already facing acute power shortage are not suitable for
electric cars. The consumption of more power would hamper their daily power
needs.
Some base models of electric cars are still very expensive because of how new
they are and the technology it took to develop them.
59 | P a g e
Chapter Three
Management Details
3.1 Training experience - management
In my second industrial training period at CodeGen VEGA project I had to
experienced many management practices which are followed by international level
companies. There I experienced management process in both VEGA project and
CodeGen as well. VEGA project is funded by CodeGen as sub project; management
process is sometimes different with the CodeGen management process. All the
management related work carried out from the Human Resources (HR) department and
they have been well trained and well capable in that manner. They maintained high
quality management process to keep the company states.
3.2 Office practice
When consider about the office practice they maintain high quality document
handling system. They maintain personal file for every employee in the company
and maintain those files according to employees’ progress. Also they use modern
attendance making system using fingerprint identification. That is really easy for
everyone in the company to mark in and out without wasting time. In VEGA they
never mind that scenario because they trust the employees in the section. HR
department keeps the total documentation process nice and clean manner.
Though in VEGA they really keep updated equipment list with details because
there are lot of expensive items. Once a month or twice they update the current
list with the existing equipment, components etc. In VEGA they maintain complete
documents for the experiments, projects which they carried out. Those documented data
very valuable when we need to revise or review those projects after long time. So they
keep that procedure with every project.
60 | P a g e
3.3 Safety procedures
As a company CodeGen follows the basic rules in safety procedures. As there
are expensive & valuable equipment they use several safety procedures to protect both
equipment and human lives. In VEGA as it is workshop safety is must condition. There
we have to work with many mechanical tools, high voltage systems, wide range
of equipment and sensitive devices & circuits. So safety is must to protect both users
and components as well. So they maintain well establish safety procedure. We had to
wear shoes inside the workshop area, use special goggles for hard work like
welding, grinding, and high voltage testing, and etc. Before use some components
we had to carefully check the connections, power rating (110 or 230), component
placement as well. Then we had to use proper places to carry out the experiments or
designs. Also when we used the tools we had to find correct tool for correct task to
assure the safety. By using such safety procedures the safety of both equipment and
user are ensured.
3.4 Financial management
Financial side is also handled by HR department. From salaries to purchases
they offer money. They do it in really control manner. In our project we need money to
purchase components. When we need some components we have to add them to the
required list. Then one day they purchase all the components. But this process change
sometimes due to the situation. Those purchases are done usually through internet
but sometimes they quick purchase few components from local market as well.
If the requirement is critical they offer money immediately to complete the project as
soon as possible. For some big amount of components, services or special components
they get few quotations and purchase based on those quotations.
3.5 Management
Management in CodeGen is well organized and planed procedure. They
maintain friendly environment entire the company area. When new comer enters to the
61 | P a g e
company staff, they conduct induction sessions for them. In that session they give total
idea about the company and working culture in the company. Also they collect our ideas
and our attitudes and interests through those sessions. That is really good chance to
understand about the company as well as to convey our ideas and interest to them.
There nobody wants us to call them “sir” or “miss” even for CEO. Everyone
call other like “aiya” or “akka”. In VEGA they follow really close relationship
each other so we can call anyone only with name also. Many functions are
organized by welfare society, toastmaster club and HR department to motivate
and encourage employees. There are cultural, entertainment, sport, employee
appreciation day, many workshops and religion etc. variety of events for everyone. Also
they celebrate birthdays of everyone in the company. At end of the month they celebrate
birthdays of the whole people in that month in grand level. Also they support for the
employees in many aspects like offering free or half rate memberships in many
organizations, easy payment methods, low interest rates for credit cards, etc. They
always take care about the employees.
There are meetings with project team in every week. There members can discuss
and share their ideas progresses of the project. Sometimes CEO also joins with those
meetings and encourages and motivates everyone to achieve the goal. As VEGA
located separately from main office and he is really passionate about the project, CEO
recently visits our site. He gives advices; share his knowledge and chatting with us also.
Also they maintain clean and nice environment throughout the company area.
62 | P a g e
Chapter Four
Summary and Conclusions
4.1 Summary
We learn lot of theories, technical methods and etc. but in the industry there we
need some other qualifications, Extra knowledge and practical experiences as well.
Without those kinds of requirements we cannot work properly in the industry. So
industrial training is very important to make a good engineer. For the second time as an
Undergraduate Trainee I got lot of experiences, lessons, knowledge etc. I’m glad to say,
I had a successful & awesome training in CodeGen International (Pvt) Ltd, “VEGA”
Project.
I was appointed as trainee of electronic field but in VEGA Project I had
a wonderful opportunity to train in many areas including Electronic, Electrical and
even Mechanical as well. When consider about the electronic field, got lot of
practical experiences those are not in books or theories. They got those kinds of
methods from their usual wellbeing practice and experience. So it is very important.
How to find design proper systems, how keep standards, how detect faults, how to
solve them, how to analyze a system practically, how to solder electronic
equipment, how to remove equipment from circuit, etc. kinds of methods were
known. Then considering about the other fields got knowledge about power
electronics systems, panel board design and wiring, various kind of equipment and
components, how to follow international standards and etc. Also I had a chance to get
experiences and knowledge about mechanical field as well. I got knowledge about
drilling, milling, cutting etc. So the training place was compact with many things that
impact to my carrier.
By the way except the technical training this was a wonderful opportunity
to move with industry people. The experience gained dealing with industry people
is very important to understand the role of the Engineer and what the society aspect
from Engineers. There I met various types of people who have various kinds of
impressions and attitudes. So it is a chance to recognize the people.
63 | P a g e
CodeGen International Pvt. Ltd. has well planned organizing system and
management system. So I also got some management experiences as well. How
to handle workers, how to incorporate with workers are some of them. Finally
it’s pleasant, friendly marvelous environment and wonderful place to work; I had
successful 3 months training in CodeGen International Pvt. Ltd. “VEGA” Project.
4.2 Conclusions
As my second industrial training I got wonderful 3 months period in CodeGen
International Pvt. Ltd. “VEGA” Project. It is a nice and friendly working place; we got
full freedom to work and enjoy ourselves in many areas. Also we got lot of experiences
and practical knowledge in technical field as well as day to day life experiences with in
this time period.
First of all training place is very pleasant and wonderful. There were many fields
to work and many researches & experiments have been going on because it’s a research
and development project. They never underestimate us as trainee undergraduates. So
they welcome us warmly and tried to give 100% effort to make our training
fruitful one. There was very friendly environment and they treated us as very friendly
manner. Always they encouraged us, taught us so many things, shared their
experiences, etc... Other than that we enjoy with them. So those reasons made my
training wonderful one.
In mean time other people in CodeGen International (Pvt) Ltd. Treated us as
very friendly manner. They welcome us warmly in many functions. Also they enjoy
with us in some co-activities. The HR people also made us courage and passionate about
the training and help to carryout wonderful three months training.
So my second training as undergraduate CodeGen International Pvt. Ltd.
wonderful one and got so many thing to my life. Finally thank all who help to get that
kind of training.
64 | P a g e
References
01. http://vega.lk/
02. http://www.codegen.co.uk/
03. http://www.cadsoftusa.com/
04. http://www.easylogix.de/products_detail.php?prog_id=1
05. http://www.pwrx.com/
06. http://www.ixys.com/productportfolio/powerdevices.aspx
07. https://www.idc-com.co.jp/search/search/Pdf/en/14/VLA106-15242
08. http://www.pwrx.com/pwrx/docs/vla503_01.pdf
09. http://www.ti.com/adc/docs/midlevel.tsp?contentId=55102
10. http://www.avagotech.com/docs/AV02-1565EN
11. http://www.avagotech.com/docs/AV02-3563EN
12. http://evobsession.com/new-electric-cars-market-2015-list/
65 | P a g e
Abbreviation
CodeGen - CodeGen International Pvt. Ltd
UK - United Kingdom
CEO - Chief Executive Officer
HR - Human Resource
HTML - Hyper Text Markup Language
CMS - Content Management System
GIS - Geographical Information System
GWT - Google Web Toolkit
R&D - Research and Development
ICT - Information and Communications Technology
USA - United State of America
EV - Electrical Vehicle
PCB - Printed Circuit Board
TI - Texas Instruments
PWM - Pulse Width Modulation
QA - Quality Assurance
IC - Integrated Circuit
DC - Direct Current
AC - Alternative Current
CAD - Computer Aided Design
IGBT - Insulated Gate Bipolar Transistor
Recommended