The Quick Guide to AC Variable Frequency Drives: Easy Variable Frequency Drive Handbook

This ebook is meant as an easy guide to any electrical/electronic/instrumentation & control engineer or technician, who would like to know how modern AC variable frequency drives work. Variable Frequency Drives (VFDs for short), also known by other names such as Variable Speed Drives, Adjustable Speed Drives, Inverter Drives, or simply as VFD drives, are seeing increasing adoption by a host of industries and establishments. The drive towards saving energy costs is a big factor, but so are also other factors such as ease of use, sophisticated functions that allow precise control of ac motors and the ability to hook up these drives to communication networks and industrial control systems such as PLC/ SCADA and DCS systems, or to Building Automation Systems. This book is a quick guide written in an easy to understand style with plenty of illustrations and diagrams that explain key concepts. Over the past two decades, this technology has become mainstream, however most of the books out there have been written ages ago and also in a style that is not easy to understand. For more information on Variable Frequency Drive technology and applications please visit https://abhisam.com The author has worked in specifying, selecting, installing and maintaining AC Variable Speed Drives for at least 10 years in his two decade experience in industry, so this ebook has been written with an audience of engineers and technicians who wish to understand the technology quickly, without too much digression, so that they can start to build their applications using VFDs. The book consists of 6 chapters as follows: 1. Basic Concepts: Here you are introduced to different kinds of motors and loads, concepts of torque, advantages of using modern VFDs instead of older ways of controlling motors and their loads, basic features of VFDs. 2. Inside a VFD: Here you get to know the innards of a typical VFD including rectifier blocks, inverter blocks, components that are commonly found in VFDs such as thyristors, IGBTs and so on.Basic concepts of working of transistors, modulation including PWM, thyristors and so on are explained. 3.VFD Functions: Here typical VFD functions such as Starting/Stopping, Acceleration/Deceleration, Speed Control, Forward/Reverse, Vector Control, V/f control, Flux vector control, Field Oriented Control, Anti Windmill control, Flying Start, PID Control, Torque Control, braking are explained in detail. 4.Energy Savings using VFDs: This chapter is dedicated to explaining how one can implement energy savings schemes, using VFDs, for different types of loads such as Fans & Blowers, Centrifugal Pumps. 5.Specifying, Selecting and Installing VFDs: This chapter lays out a roadmap for implementing your own VFD project including analyzing the load,evaluating use of a VFD versus traditional controls, use of temperature and altitude derating,overload capacity, harmonics, installation in panels, earthing, maximum cable lengths. 6. Using VFDs with DCS/PLC systems: Many modern plants utilize either Distributed Control Systems (DCS) or Programmable Logic Controllers (PLCs) as a Control System and many times it is useful for the VFD to be integrated into such systems. This chapter covers those aspects. As you can see, this quick guide covers pretty much everything that you, as an engineer or technician, need to know about AC VFDs to start implementing this technology in your plant. Read more