Induction motor and sequence reactance

AI Thread Summary
Induction motors consist of three sequence components: positive, negative, and zero sequence components. The discussion seeks clarification on the meanings of running reactance, starter reactance, and standstill reactance in the context of induction motors. It questions whether any of these reactances represent the positive sequence reactance in an unsymmetrical fault system. The reference to IEC 60909-0 provides a formula for determining the impedance of asynchronous motors in positive and negative sequence systems. Understanding these reactances is crucial for analyzing motor performance under different operational conditions.
honyeehong8692
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Hello! This is my second post about sequence reactances. This time- its in induction motor.

To my understanding ( once again ) -

In any network (symmetrical or unsymmetrical) , there would be 3 components- positive sequence component, negative sequence component and zero sequence component.

Question:

In induction motors, what do the: running reactance, starter reactance and standstill reactance mean?

and,

Do anyone of them signify/mean the positive sequence reactance of a unsymmetrical fault system?
 
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BTW, a prompt reply is very much appreciated. Please and thank you!
 
According to IEC 60909-0 Ch. 3.8 Asynchronous motors 3.8.1 General:
The impedance ZM = R M + jXM of asynchronous motors in the positive- and negative-sequence systems can be determined by:
ZM=1/(ILR/IrM)*UrM/sqrt(3)/IrM=UrM^2/SrM//(ILR/IrM)
Where
UrM is the rated voltage of the motor;
IrM is the rated current of the motor;
SrM is the rated apparent power of the motor (SrM = PrM/(effrM* COSfiTM);
PrM is the rated motor power [kW]
effrM is the rated motor efficiency
COSfiTM is the rated motor power factor
ILR/IrM is the ratio of the locked-rotor current to the rated current of the motor.
 
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