All about VFDs
This 15-minute video, “Variable frequency drives explained—VFD basics IGBT inverter” shows how they work in electrical engineering and power electronics. It demonstrates where and why to use a VFD or VSD, alternating current, direct-current, singlephase, three-phase, frequency, rectifier, DC bus, inverter, capacitor and pulse width modulation (PWM). It’s part of a series located here.
DoE improves performance
This 116-page article, “Improving motor and drive system performance: a sourcebook for industry” from the U.S. Dept. of Energy’s Industrial Technologies Program (ITP), presents a system approach, indications of poor system design, motor types and operating characteristics, and shows how to match motors and drives to their applications.
Power for speed and torque
This 43-minute video, “Introduction to motor drives” by Jim Pytel of Big Bad Tech, covers power electronics devices that vary the speed and torque of a motor under its direction by varying the supplied voltage magnitude and frequency.It also reviews properties that influence synchronous speed, discusses rectification, inversion and filtration, and examines motor drive specifications and programming.
Design, validation testing
This online library, “Accelerate the design, validation and texting of motors and drives” contains ebooks, whitepapers and case studies on testing motor and drive systems, developing premium efficiency motors, measurements challenges, AC kinetics and other topics.
AC basics and installation
This 38-minute video, “Drives 101: basic features of AC drives,” shows how to control motors speeds, save energy and develop control strategies. It also covers pulse width modulation (PWM), constant torque loads, affinity laws for centrifugal loads, digital/analog inputs, slip compensation, braking methods and other topics.
There’s also a link to a second, 27-minute video, “Best practices for installing AC drives,” which has strategies, suggestions and technical advice.
Different drive types
This online article “Types of motor drives” covers DC and AC drives and the motors that rely on them, servomotor drives, controllers and applications, and stepper motors and applications.
Troubleshoot drives, panels
This eight-minute video, “How to troubleshoot and diagnose a non-working VFD” by Craig Hartman, presents a step-bystep guide for inspecting different parts of systems to diagnose non-working VFDs or VFD panels that aren’t powering up, showing error codes or running rough. It also shows how to check maximum frequency, set acceleration times, disconnect motors and measure cables.
A second, five-minute video, “How to wire a VFD” by Steve Quist, provides instructions for wiring single-phase or three-phase Mitsubishi D700 series VFDs.
Three-phase inductive parts
This online article, “Get schooled: AC motor basics” by Jeff Payne, covers the essential parts of three-phase AC inductive (asynchronous) and synchronous motors, namely the stator and rotor, as well as rotating magnetic fields, soft starters and VFDs, controls and common applications.
Soft starter vs. VFD
This seven-minute video, “What’s the difference between a VFD and soft starter?,” examines their internal workings and applications, so users can determine which they might want to implement. For example, it shows how aa typical, threephase soft starter uses six thyristors or silicon-controlled rectifiers oriented in an anti-parallel configuration to start electric motors smoothly.