1. What's a Frequency Inverter?
Frequency inverter also called frequency converter, it is a power control conversion device to convert normal
power supply (50Hz or 60Hz) to another frequency power by inner power semiconductor on/off behaviors, to
control electric motors in variable speed operations. Variable frequency control is changing the frequency
supply to the motor stator windings to achieve variable speed control purpose.
The frequency inverter is mainly consisted of rectifier (AC to DC), filter, inverter (DC to AC), braking unit,
drive unit, detection unit and micro processing unit etc. The control circuit controls main circuit, the rectifier
circuit converts AC power into DC power, DC intermediate circuit smoothing the rectifier circuit output, then
the inverter circuit reverse DC current into AC current again.
A variable-frequency drive (VFD) (also termed adjustable-frequency drive, variable-speed drive, AC drive,
micro drive or inverter drive) is a type of adjustable-speed drive used in electro-mechanical drive systems to
control AC motor speed and torque by varying motor input frequency and voltage
Application considerations
 Frequency Converter for Pumps
 Frequency inverter for heavy duty application (mining)
 Frequency inverter energy savings for Thermal Power Plant
 Frequency inverter in Oil Industry
 Frequency inverter reconstruction to save energy
 Frequency inverter in power plant
 Frequency inverter on pumps for energy saving
 Frequency inverter for fans for energy saving
 Frequency inverter in Screw extruding machines
 Inverter drive in injection machine
 Frequency inverter in Automatic Disk Type Plastic Molding Machine
 Frequency inverter in NC Lathe
 Frequency inverter for Air Compressor
 Inverter in injection molding machine advantages
 Frequency inverter in hoist & crane
List of VFD company
 LS
 ABB
 Mitsubishi VFD
 Hitachi VFD
 Saftronics VFD
 Omran
 Delta