energy
energy
Frequency, when referring to waves, is directly proportional to the velocity of the wave. Frequency in inversely proportional to the wavelength.
F is directly porportional to P
Variable voltage variable frequency
When a variable is directly influenced by another variable it is known as a dependent variable. Conversely, a variable that isn't directly affected by another variable is known as a independent variable.
Temperature is only sometimes directly proportional to frequency. Temperature however is not always directly proportional to frequency in all cases.
definitly it give more efficient than variable stator voltage.............but in variable frequency ...............the frequency is not only variable....it is E/F control.because to maintain constant flux......... USUALLY THIS SPEED CONTROL IS ODOPTING IN INDUSTRIES......
Many companies sell variable frequency drives. ABB, GE, Eaton, Baldor, AC Tech, Honeywell, Toshiba, IDM, Hitachi, and Yaskawa are major brands that sell variable frequency drives.
Single phase variable frequency drives are commercially available. Building it by an individual is complicated.
A variable-frequency drive (VFD) is a system for controlling the speed of a rotational or linear alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor.[1][2][3] A variable frequency drive is a specific type of adjustable-speed drive. Variable-frequency drives are also known as adjustable-frequency drives (AFD), variable-speed drives (VSD), AC drives, microdrives or inverter drives.
Main function of Variable Frequency Drive is to be able to run the AC Induction motors at different speeds (by changing the frequency). The speed is a function of frequency. N - Speed. F - Frequency P - Pole N= ( 120 x F)/ P
The signals frequency directly.