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Small variable-frequency drive Chassis of above VFD (cover removed). A variable-frequency drive (VFD, or adjustable-frequency drive, adjustable-speed drive, variable-speed drive, AC drive, micro drive, inverter drive, variable voltage variable frequency drive, or drive) is a type of AC motor drive (system incorporating a motor) that controls speed and torque by varying the frequency of the ...
A vacuum fluorescent display (VFD) is a display device once commonly used on consumer electronics equipment such as video cassette recorders, car radios, and microwave ovens. A VFD operates on the principle of cathodoluminescence , roughly similar to a cathode-ray tube , but operating at much lower voltages.
In vector control, an AC induction or synchronous motor is controlled under all operating conditions like a separately excited DC motor. [21] That is, the AC motor behaves like a DC motor in which the field flux linkage and armature flux linkage created by the respective field and armature (or torque component) currents are orthogonally aligned such that, when torque is controlled, the field ...
Download as PDF; Printable version; In other projects Wikidata item; Appearance. ... VFD may refer to: Government. Veterinary Feed Directive, United States;
The variable-frequency drive controls the speed of compressor motor. The compressor is specifically designed to run at different motor speeds to modulate cooling output. Variable speed operation requires an appropriate compressor for full speed operation and a special compressor lubrication system.
When changing VFD frequency in standard low-performance variable-torque applications using Volt-per-Hertz (V/Hz) control, the AC motor's voltage-to-frequency ratio can be maintained constant, and its power can be varied, between the minimum and maximum operating frequencies up to a base frequency. Constant voltage operation above base frequency ...
In the past, VFDs that have a capacity greater than 3 hp (2.2 kW) were costly, thus making the rotary phase converter (RPC) an attractive alternative. However, modern VFDs have dropped considerably in cost, making them more affordable than comparable RPCs. Also working in the VFD's favor is its more compact size relative to its electrical capacity.
A vacuum fluorescent display (VFD) is a display device used commonly on consumer-electronics equipment such as video cassette recorders, car radios, and microwave ovens. A VFD operates on the principle of cathodoluminescence, roughly similar to a cathode ray tube, but operating at much lower voltages.