[PDF] Electric Motors and Drives by Austin Hughes

PREFACE:Like its predecessors, the third version of this ebook is meant primarily for non-specialist customers and college students of electrical motors and drives. My unique intention was to bridge the hole between specialist textbooks (that are pitched at a degree too tutorial for the common person) and the extra prosaic ‘handbooks’, that are stuffed with helpful element however present little alternative for the event of any actual perception or understanding.

The truth that the second version was reprinted ten occasions indicated that there had certainly been a niche out there, and {that a} third version could be worthwhile. It was additionally gratifying to study that though the unique ebook was not supposed as yet one more undergraduate textbook, lecturers and college students had welcomed the ebook as a mild introduction to the topic.

The intention all through is to offer the reader with an understanding of how every motor and drive system works, within the perception that it is just by realizing what ought to occur that knowledgeable judgements and sound comparisons could be made. Provided that the ebook is aimed toward readers from a variety of disciplines, introductory materials on motors and energy electronics is clearly vital, and that is introduced within the first two chapters.

Many of those fundamental concepts crop up often all through the ebook, so except the reader is well-versed within the fundamentals it might be clever to soak up the primary two chapters earlier than tackling the later materials. As well as, an consciousness of the fundamental concepts underlying suggestions and closed-loop management is critical with a purpose to observe the sections coping with drives, and this has now been supplied as an Appendix.

The ebook explores a lot of the extensively used trendy sorts of motors and drives, together with typical and brushless d.c., induction motors (mains and inverter-fed), stepping motors, synchronous motors (mains and converter-fed) and reluctance motors. The d.c. motor drive and the induction motor drive are given most significance, reflecting their dominant place when it comes to numbers.

Understanding the d.c. drive is especially necessary as a result of it’s nonetheless extensively used as a body of reference for different drives: those that develop grasp of the d.c. drive will discover their know-how invaluable in coping with all different sorts, notably if they’ll set up a agency grip on the philosophy of the management scheme.

Youthful readers could also be unaware of the unconventional adjustments which have taken place over the previous 40 years, so maybe a few paragraphs are acceptable to place the present scene into perspective. For greater than a century, many various kinds of motors had been developed, and every grew to become carefully related to a specific utility.

Traction, for instance, was seen because the unique protect of the sequence d.c. motor, whereas the shunt d.c. motor, although outwardly indistinguishable, was seen as being fairly unsuited to traction purposes. The cage induction motor was (and nonetheless is) essentially the most extensively used however was judged as being suited just for purposes that referred to as for fixed pace.

The explanation for the plethora of motor sorts was that there was no straightforward means of various the availability voltage and/or frequency to acquire pace management, and designers had been due to this fact pressured to hunt methods of offering pace management throughout the motor itself.

All types of ingenious preparations and interconnections of motor windings had been invented, however even the most effective motors had a restricted vary of working traits, and all of them required cumbersome management tools gear-control, which was manually or electromechanically operated, making it troublesome to rearrange computerized or distant management.

All this modified from the early 1960s when energy electronics started to make an impression. The primary main breakthrough got here with the thyristor, which supplied a comparatively low-cost, compact and simply managed variable-speed drive utilizing the d.c. motor.

Within the 1970s, the second main breakthrough resulted from the event of power-electronic inverters, offering a three-phase variable-frequency provide for the cage induction motor and thereby enabling its pace to be managed.

These main developments resulted within the demise of lots of the particular motors, leaving the vast majority of purposes within the palms of comparatively few sorts, and the emphasis has now shifted from complexity contained in the motor to sophistication in provide and management preparations. From the person’s perspective this can be a combined blessing.

Higher flexibility and superior ranges of efficiency can be found, and there are fewer motor sorts to think about. But when something greater than fixed pace is known as for, the person can be confronted with the acquisition of an entire drive system, consisting of a motor along with its related energy electronics bundle.

To decide on properly requires not just some information of motors, but additionally the related power-electronics and the management choices which might be usually supplied.

Electric Motors and Drives Fundamentals: Types and Applications PDF

Author(s): Austin Hughes, Bill Drury

Publisher: Elsevier, Year: 2019

ISBN: 978-0-08-102615-1

Download Electric Motors and Drives Fundamentals, Sorts and Functions Third Version by Austin Hughes PDF