V. Rajini and V. S. Nagarajans
Foreword
It gives me great pleasure to write the foreword to the book entitled, Electrical Machine Design.
Electrical machines play a vital role in domestic and industrial fronts. Hence, it is essential that students of electrical engineering have a strong grounding in electrical machines. Conventional courses in electrical machines are not adequate for the purpose of understanding as they throw light on the construction, principle, characteristics and testing. A deeper understanding is possible only when they study the design aspects and their influence on the performance of the machines. It is thus necessary to have a course on electrical machine design, suitable for study by undergraduate students of electrical engineering.
This book is designed to meet the needs of a textbook for a course in electrical machine design. It gives a comprehensive design aspects of DC and AC machines with an appropriate introduction to basic design considerations and the magnetic circuits involved. Introduction to the design and analysis of the machines using the finite element analysis is also included as one chapter, to enable the readers to have a much deeper understanding. A design process always involves a long iterative process and a designer is required to take decisions in conflicting situations. The design procedure of all the machines is given as simple flowcharts for the reader to understand the iterative nature of design process. In addition to the worked examples, most chapters include number of problems designed to test the grasp of the subject. The readers will also appreciate the pedagogical practices followed in this book.
This book is the outcome of the long experience of the authors in teaching electrical machines and allied courses. The authors have made a commendable effort to present the contents in a clear and lucid form.
I hope this book will be well received by students, teachers and practicing engineers.
Dr V. Kamaraj
Professor and Head
Department of Electrical and Electronics Engineering
SSN College of Engineering
Chennai
Preface
Electric machines have become a part and parcel of our day-to-day lives. They play an inevitable role, right from a small toy to an electric power plant. Hence, the knowledge of their operating characteristics and performance is essential to Electrical Engineering graduates. Also, it is important for them to learn the design of these machines considering various technical and economical aspects. Hence, this book is intended to serve as a textbook for those who are interested in learning the design of electrical machines.
The target audience also include academicians, students of B.E./B.Tech. (Electrical and Electronics Engineering, Electronics and Instrumentation Engineering and Instrumentation and Control Engineering) and industrial ...
About the Authors
V. Rajini has been working as a Professor in the Department of Electrical and Electronics Engineering, SSN College of Engineering. She has 22 years of teaching and research experience. She was graduated from Annamalai University in 1992 and subsequently obtained her Ph.D. in High Voltage Engineering from Anna University in 2008. She has published over 90 research publications in referred journals. She has completed various projects funded by SSN Trust and AICTE and MNRE. She is currently working on the fields of Insulating Materials, High Voltage Applications in Process Technologies, Hybrid Electric Vehicles, Power Electronics for HV Applications, Solar Photovoltaic and Wind Energy Systems.
She has received Best paper awards in various conferences, has also received the Best teacher awards. Ms Rajini is the recipient of CTS SSN Best Faculty Award 2011 and distinguished scientist award 2016 by VIRA foundation for her contributions in the field of high voltage engineering. She is a senior member of IEEE and Life member of ISTE.
V. S. Nagarajan has been working as an Assistant Professor in the Department of Electrical and Electronics Engineering since June 2014. He did his B.E. (EEE) in SSN College of Engineering and was ranked 2nd in the college and 21st in the Anna University. After his graduation, he joined CTS as Programmer Analyst and worked there for about a year. Later, he did his Masters in Power Electronics and Drives in SSN College of Engineering scoring a CGPA of 9.34 out of 10 and was ranked 2nd in the college and 4th in the Anna University. He is currently pursuing Ph.D. in the field of Electrical Machine Design and Control under Anna University. He was the recipient of merit scholarship both for B.E. and M.E. and also the merit scholarship by Ministry of Human Resources and Development, Govt. of India (For GATE score). He has been awarded with four silver medals and one gold medal for being the topper of the department in various semester examinations. He has also been awarded with The Chairmans Silver Medal and College Silver Medal for securing Anna University ranks in B.E. and M.E., respectively. He has published six papers in National/International Journals and Conferences.
1
BASIC DESIGN CONSIDERATIONS OF ELECTRICAL MACHINES
1.1 Principles of Design
An electric machine is an electromechanical device that comprises the stationary and moving parts combined together to generate, transform or utilize the mechanical/electrical energy. Electric machines are used in applications like transportation, aerospace, defence and industrial automation industries. Electric motor-driven systems that drive pumps, fan, blower systems and air compression have become common in industries. Good engineering design is the heart of all such applications. Engineering design is the application of science, technology and invention to produce machines to perform specified tasks with optimum economy and efficiency.