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Modeling Motor in EMTP

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tiftif

Electrical
Joined
Jul 16, 2010
Messages
13
Location
CA
I have motor data as magnetizing inductance => 5 pu. I have stator and wound rotor resistance and inductance. All like 0.0x pu.
I need
Rs: Resistance of each stator coil
Lls: Stator leakage inductance
Rr1: Resistance of the rotor windings from stator side.
Llr1: Rotor leakage inductance from stator side.

So I'll put these four to be equal to the 0.0x pu above. No change.

What about
Lmd: d-axis main inductance
Lmq: q-axis main inductance

Are these equal to the magnetizing inductance i.e. 5 pu?
 
Let's take kVAbase=kVArated Srated=sqrt(3)*(Irated*Vrated)/1000 [kVA]
Zbase=Vrat^2/Srated
Let's say it is an induction motor of: P[HP]=100 HP;
Vrat=480 V 4 poles 60 hz
P[kW]=100*0.746=74.6 ; efficiency=90%;p.f.[cos(fi)]=0.9 ; Srated=74.6/0.9/.9= 92 kVA
Zbase=Vrat^2/Srat/1000=2.5 ohm
Xm=5p.u.=5*2.5=12.5 ohm ; Lm=12.5/(2*π*60)=0.033 H
Xm= magnetizing reactance=2*π*60*Lm [ohm]
Lm=magnetizing inductance[H]
If it is about a synchronous motor then Lmq is different than Lmd.For an induction motor Lmq=Lmd
 
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