What are variable frequency drives? What are AC motors?

Variable frequency drives (VFDs), or ac drives, are designed to reduce energy usage by controlling the speed of the motor and can offer cost-effective benefits for plants. AC motors convert electrical energy into mechanical rotating or linear energy to operate industrial equipment.
Motors, Drives September 24, 2012

Permanent magnet motors outperform induction motors in many applications

Permanent magnet synchronous motors offer significant advantages on high-energy-consuming and high-dynamic applications, compared to induction motors. See table, photo gallery.

By Harald Poesch
Motors, Drives April 1, 2006

Thinking inside the box: Energy costs drive ac-drive innovations

The types of ac drives used with ac induction motors are V/Hz, encoderless and flux vector. While there are many drives available for synchronous and servo motors, induction motors have the majority of applications. Sensorless vector control is the same as encoderless vector control, which better describes its operation.

By Jack Smith, Senior Editor
Power Systems June 10, 2004

Basics of power management software

Powerful analytical tools — software, PCs, networks, and the internet — are within a click of the mouse. Power monitoring equipment captures data; software analyzes critical data required for responsible electrical energy management. Power management software tools provide control over how you manage your use of electricity.

By Jack Smith, Senior Editor, Plant Engineering magazine
Electrical October 10, 2003

Basics of how to minimize harmonics

The August 14, 2003 blackout emphasized that power quality should not be taken lightly. The blackout was caused by, and affected the power grid — our nation's electrical infrastructure. The issues raised by this event should and will come under scrutiny. Just as the nation looks at its power quality issues, plant engineers must look at power quality issues inside the plant.

By Jack Smith, Senior Editor, Plant Engineering Magazine
Motors, Drives March 1, 2001

Choosing between IEC and NEMA motor controls

Key Concepts NEMA and IEC motor controls differ in size, ruggedness, and complexity. The solid-state overload relay is common to both NEMA and IEC motor controls.

By Jack Smith, Senior Editor, Magazine