The way we control the speed of fan motors or pump motors has tremendously changed in the past two decades with the introduction of variable-frequency drives (VFDs), aka variable-frequency controllers ...

The topic of motors and motor control techniques is wide and varied. Part one of this two-part article will cover the principles of alternating-current (AC) motor operation and control. Part two will ...

Speed, torque, and horsepower are three inter-related parameters in motor control. The speed of a motor, measured in revolutions per minute (rpm), defines a motor's ability to spin at a rate per unit ...

October 2025 marks the 50th anniversary of the Low Voltage Variable Speed Drive (LV VSD), which was used in a commercial ...

A dc motor driving an ac alternator was used to simulate an asynchronous wind electric generator. The output was used to drive a commercial air conditioning unit containing a hermetically sealed three ...