variable-frequency drive , VFD (abbreviation)
adjustable-frequency drive , AFD (abbreviation)

Nowadays, variable-frequency drive motors are more commonly used instead.

These fans use airfoils instead of flat blades and feature onboard variable-frequency drives.

Variable-frequency drives are also categorized by the following load torque and power characteristics:

Speed control requires a variable-frequency drive.

Nowadays, synchronous motors are frequently driven by transistorized variable-frequency drives.

Some EMUs in this series use variable-frequency drive motors.

The variable-frequency drive article provides additional information on electronic speed controls used with various types of AC motors.

Transistorized inverters with variable-frequency drive can now be used for speed control, and wound rotor motors are becoming less common.

For AC motors, applications include variable-frequency drives, motor soft starters and excitation systems.

Today speed control by use of slip ring motor is mostly superseded by induction motors with variable-frequency drives.

It can occur in motors powered by variable-frequency drives, as often used in heating, ventilation, air conditioning and refrigeration systems.

Similar to a variable-frequency drive, they use a microprocessor to control solid-state power switching components to maintain balanced three-phase voltages.

At the mixing stage, variable-frequency drive controlled pumps add the surfactant and flocculating polymers to the mud in predetermined concentrations.

Variable speed controlled AC motors are provided with a range of different power inverter, variable-frequency drive or electronic commutator technologies.

The () is a Japanese manufacturer of servos, machine controllers, Variable-frequency drive , switches and robots.

Variable-Frequency Drive, also called an Adjustable Frequency Drive.

(See related: variable-frequency drive ) Switching states are developed for positive, negative and zero voltages as per the patterns given in the switching Table 1.

Line reactors are generally installed in motor driven equipment to limit starting current, and may be used to protect Variable-frequency drives and motors.:)

Before solid-state devices became available, variable-frequency drives used rotary machines and the General Electric Company obtained several patents for these in the early 20th century.

RMS sensing is necessary for measurements on non-sinusoidal periodic waveforms, such as found in audio signals and variable-frequency drives.

Squirrel cage induction motors are very widely used in both fixed-speed and variable-frequency drive (VFD) applications.

Feature IGBT variable-frequency drive.

Load Commutated Inverter, a specific topology of Power inverter used in variable-frequency drives.

Variable-frequency drive (VFD)

Because Azipod units utilize fixed-pitch propellers, power is always fed through a variable-frequency drive or cycloconverter that allows speed and direction control of the propulsion motors.

All variable- speed pumping equipment will employ adjustable-frequency drives.