VFD set up
VFD set up
(OP)
guys, .....question ...this might sound very elemetry but, I had to ask
what determines the type of VFD set??(constant torque, constatnt speed, constant power)
is it set by changing the drive parameter ??? or it is determine by the type of load or the motor??
what determines the type of VFD set??(constant torque, constatnt speed, constant power)
is it set by changing the drive parameter ??? or it is determine by the type of load or the motor??





RE: VFD set up
A load that has the same torque independent of speed is a constant torque load. A hoisting system is such a load. There are no constant speed loads (except if you are running against a synchronous motor connected to the grid). A constant power load is usually a winder where web force is constant so that torque increases and speed decreases as coil diameter grows. There are also loads where torque increases with speed - a fan and its quadratic speed/torque curve is a common example.
Gunnar Englund
www.gke.org
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Half full - Half empty? I don't mind. It's what in it that counts.
RE: VFD set up
Dan - Owner

http://www.Hi-TecDesigns.com
RE: VFD set up
The definition of "constant speed" in the mechatronics world is "Instantaneous Speed = Average Speed". I don't see that as possible in a VFD application given that a motor is all about torque and speed. Close, but not really there.
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