Variable frequency Drive (VFD), also called Inverter or Drive controllers, is Inverter translated by whose Inverter is not Inverter.
Frequency converter is a kind of adjustable speed drive system, is the application of frequency conversion drive technology to change the working voltage frequency and amplitude of ac motor, to smooth the control of ac motor speed and torque, the most common is the input and output are ac/AC converter ac.
Before in frequency converter, motor speed adjustment of application should be through the dc motor to complete, otherwise is to through the use of a built-in coupling machine v motor, in operation by coupling machine dropping speed of motor, frequency converter simplifies the work above, the device volume, greatly reduce the maintenance rate.
However, there are high-frequency switching signals on the power line and motor line of the frequency converter, which will cause electromagnetic interference, and the power factor on the input side of the frequency converter is generally not good, which will generate the power end harmonic.
Frequency converters are used in a wide range of applications, from small household appliances to large field grinders and compressors.
About a third of the world's energy is consumed in motors that drive fixed-speed centrifugal pumps, fans and compressors. Market penetration of frequency converters is still low.
The significant improvement in energy efficiency is one of the main reasons for using frequency converters.
Frequency converter technology is closely related to power electronics, including semiconductor switching elements, frequency converter topology, control and simulation technology, and control hardware and firmware advances.