Operation On A Generator; How Can I Estimate The Relative Line Short-Circuit Power When Directly Operated On A Generator; How Can I Estimate The Relative Line Short-Circuit Power When Operated On A Generator Via A Matching Transformer - Siemens SINAMICS S120 Engineering Manual

2 Examples and tips
2.2

Operation on a generator

How can I estimate the relative line short-circuit power when directly operated on a
generator?
As the ohmic resistance of the generator when compared to the inductive resistance is
very low, it can be neglected for the calculation.
As a consequence, the calculation is only made with the relative subtransient reactance
of the generator ��''
For a simplified calculation, the following applies for the generator impedance:
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With the formulas used in Chapter
over for the line short-circuit power at connection point IPC as follows:
The relative short-circuit power at the connection point IPC is therefore:
How can I estimate the relative line short-circuit power when operated on a generator via a
matching transformer?
Also here, the relative subtransient reactance of the generator ��''
For the calculation, the following applies for the generator impedance:
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With the formula for the generator impedance and the other formulas used in Chapter
"1.3.4.3 Calculations", the short-circuit power at connection point IPC is as follows:
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The relative short-circuit power at the connection point IPC is therefore:
Engineering manual S120 Booksize
Entry ID: 109808992, V1.0,
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