Control technology

Electrical Apparatus, Feb 2005 by Nailen, Richard L

Control technology Variable Speed Drive Fundamentals. By C.A. Phipps. The Fairmont Press, Inc., 700 Indian Trail, Lilburn, Ga. 30047; (770) 925-9388. $84 (hardbound). 212 pages.

A review of the first edition of this book that appeared in the Oetober 1996 Electrical Apparatus applies to most of this one as well. Written for the drive user or installer, without a great deal of electronic theory or math, the volume deals with operating principles of both mechanical and electrical drives. Retired as a control industry manager, the author draws on 50 years of electrical industry experience, most of it in drive application.

The bulk of the easy-to-read text concerns a-c and d-c electronic drives, including enclosures and heat transfer, economic calculations, applications, and case histories. One chapter offers maintenance and troubleshooting advice for pulsewidth-modulated drives. Another gives step-by-step procedures for starting up a typical drive and setting its operating parameters.

This is a quick scan of a broad field of technology. Harmonics and vector control are mentioned but not treated in detail. But users are cautioned about many drive problems such as torsional oscillation, mechanical resonance, and overvoltages from PWM inverters. A limited list of drive manufacturers and available software, electrical formulas, and a useful glossary of drive terms conclude the book.

In November 1997, we reviewed the second edition of this book, which offered significant changes, including added material on harmonics and the effects of non-linear loads. The index and appendices were expanded. The latest third edition makes no changes at all, however, except in those appendices, mostly in the listing of drive manufacturer identities and contact information. Unfortunately, since six years have elapsed, much of that "newer" material is now outdated. Except for that, anyone interested in the field who doesn't have the second edition will find this one useful. Otherwise, nothing is to be gained by buying the third.-RLN