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VFD (Variable Frequency Drive) Basics 101
What is a VFD and how does it work?
VFD How they work
VFD INSTALLATION/REPLACEMENT VIDEO :)
• HVAC VFD Installation ...
A Variable Frequency Drive (VFD) is a type of motor controller that drives an electric motor by varying the frequency and voltage supplied to the electric motor. Other names for a VFD are variable speed drive, adjustable speed drive, adjustable frequency drive, AC drive, microdrive, and inverter.
Applications:
Variable Frequency Drive (VFD) can be used in lots of fields. Variable frequency drives are widely used to control the speed of AC motors, like conveyor systems, blower speeds, pump speeds, machine tool speeds, & other applications that require variable speed with variable torque.
Basics:
These variable-frequency drives (VFDs) accurately control the speed of standard AC induction or synchronous motors. VFDs manipulate the frequency of their output by rectifying an incoming AC current into DC, and then using voltage pulse-width modulation to recreate an AC current and voltage output waveform.
Benefits/Advantages:
One of the main advantages of using a VFD is the energy cost saving sassociated with speed control. When using belts, sheaves, or gearboxes to reduce speed, the motor still runs at full speed; however, a VFD reduces the actual motor speed, which reduces the amps drawn by the motor.
A VFD can provides soft-start capability which reduces the inrush current when motors start up, and thereby reduces the mechanical stress on the motor and improves the motor reliability.
Function:
A VFD (Variable Frequency Drive), or rather a VVFD (Variable Voltage and Frequency Drive) is a precision electronic device specifically designed and used to control the speed of AC induction motors (single as well as three phase) without affecting the electric consumption, torque, impedance, magnetic flux, etc.
Efficiency:
At half its rated operating speed, the fan delivers 50% of its rated airflow but requires only 1/8 full-load power. Even with a reduced motor efficiency of 77.8% and drive efficiency of 86%, with adjust- able speed operation the power required by the fan and the VFD is only 2.8 kW.
A VFD has many benefits including improved process control, energy savings, higher reliability and reduced wear and tear. AC motors are very common in manufacturing and processing plants. When a motor runs at half of its maximum speed, it consumes significantly less energy than it does at full speed.
Energy efficiency is needed to not only meet burgeoning power requirements, but curtail greenhouse emissions. On a global scale, energy efficiency can reduce greenhouse emissions by around 40%.