Re: [CAD_CAM_EDM_DRO] handle inertia was (Re: Mariss' power supply circuit)

Hello Less,
that is an excelent point that imo should be handled as a own thread
I have to hande some smaller cases where you see an negative efect out
of this problem.
example a 2 meter knife grinder where the carriage bumps fast slow fast
slow over the hole lenght. Result waves in the knife edges.

Right now I go to adjust a pump regulatio control with so much
fluctuation that the pump cavitates although it is driven by an
inverter.
Regards
Sven Peter

Les Watts wrote:

>
> > hay how about a livley discussion on rotor/system inertial mismatches
> > tomorrow night!!
> >
> > John H. Berg
>
> I would be happy to discuss inertial matches. I have been modeling some
> machine components as transmission lines. With some components (longer
> ballscrews) I have tried terminating them in their characteristic mechanical
> impedance with good results.
>
> I am also playing around with second order mechanical resonant absorbers
> particularly on gantries.
>
> And as I have mentioned before EMC has the basic bandwidth capability
> to do some anti-vibration functions.
>
> Although my latest system is a close inertia match on x I do not think it is
> of overiding importance. I think one can get higher accelerations with
> the same (complex) power by driving with a lower mechanical impedance
> even though system energy transfer is not optimum. Theoretically I^2R in
> the motor armature is minimised at 1:1 (for a given output) but that
> often is not a particularly critical design requirement. I have a 2:1 and
> 3:1
> inertia mismatch on y and z on the latest machine.
>
> Look forward to discussing!
>
> Les
>
> Leslie Watts
> L M Watts Furniture
> Tiger, Georgia USA
> http://www.rabun.net/~leswatts/wattsfurniturewp.html
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