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Inertia Constant

Inertia Constant

Inertia Constant

(OP)
All,

Can anyone explain the relationship between J = GD(Squared)/H and kW sec/kVA.

Regards

G

RE: Inertia Constant

Both equations appear are for Units of Energy or Work.
It appears improper use of Upper/Lower case was used in the second equation.
J= GD(squared)/H
J= Joules,(SI unit of Energy)
G= Gauss, (GCS unit of flux Density)
H= Henry, (SI unit of Inductance)

kW sec/kVA
k= (Lower Case) (SI prefix for 10'3)
K= (Upper Case)Kelvin (SI Unit of temperature)
W= Watt, (SI unit of Power)
VA= Voltampere, (SI Unit of "Aparrent-Power")

Neither formula appears to have any merit that would make it a legitimate statement...

RE: Inertia Constant

York - you have misinterpretted the units.

J is moment of inertia in kgm^2
H = (1/2) * J w0^2/Sbase where S is base power has units of seconds interetted as the amount of time to develop the syncronous kinetic energy ((1/2) * J w0^2) at rated power Sbase.

I have to look up the other two... it has been awhile.

RE: Inertia Constant

electripete;
Sorry for the confusion, I was responding to the "Units" as posted. I could be outdated, but using the latest tables I can find, I see that by "SI" postings that;

J=    Joules
I,J=  kg^m2 (Moment of Inertia)
H=    Henrys

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