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Variable-frequency drive

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, VVVF 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 input electricity.…

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Application considerations

HarmonicsNon-linearElectric power companyAC gridSubstation
22 related topics

System description and operation

ControllerThree-phaseInduction motorSingle-phaseSynchronous motors
56 related topics

VFD types and ratings

DiodeSCRPulse-amplitude modulationDC chopperDarlington Pair
11 related topics

History

StrömbergMartti HarmoinenFiHelsinki Metro
4 related topics

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Overview

History

System description and operation

Starting and software behavior

Benefits

VFD types and ratings

Application considerations

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Variable-frequency drive

Nodes121
Edges120
Triples27
Avg. degree1.98
Density0.016529
Components1

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Variable-frequency drive

Top relations

related to history · 7
Variable-frequency drive → Finland, Helsinki Metro, Martti Harmoinen, Pulse-width, PWM, SAMI10, Strömberg
related to Load torque and power characteristics · 2
Variable-frequency drive → Variable, Variable-frequency
is a · 1
Variable-frequency drive → device used in a drive system consisting of the following three main sub-systems
related to System description and operation · 1
Variable-frequency drive → AC

Important terminology Word statistics

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Important terminology

motor speed drives ac drive power vfd torque voltage frequency control load output dc motors inverter energy current vfds used

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Variable-frequency driveis adevice used in a drive system consisting of the following three main sub-systems0.90text
common DC bus or solar applicationsinstance ofin some applications0.80text
drives are configured as DCinstance ofin some applications0.80text
Modbusinstance ofNetworked involves transmitting the intended speed over a communication protocol0.80text
Modbus/TCPinstance ofNetworked involves transmitting the intended speed over a communication protocol0.80text
EtherNet/IPinstance ofNetworked involves transmitting the intended speed over a communication protocol0.80text
or via a keypad using Display Serial Interface while hardwired involves a pure electrical means of communicationinstance ofNetworked involves transmitting the intended speed over a communication protocol0.80text
fault codesinstance ofIt is also common for VFDs to provide debugging information0.80text
the states of the input signalsinstance ofIt is also common for VFDs to provide debugging information0.80text
in hoistsinstance ofwhere the speed and torque can be in any direction0.80text
elevatorsinstance ofwhere the speed and torque can be in any direction0.80text
and hilly conveyorsinstance ofwhere the speed and torque can be in any direction0.80text

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