Why is S_{RATED}=I_{RATED}V_{RATED} Insufficient for Synchronous Generators?

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The formula S_{RATED}=I_{RATED}V_{RATED} is insufficient for synchronous generators because it does not account for the three-phase nature of the system. In this case, the apparent power must be calculated using the formula S = √3 * V_line * I_line, where V_line is the line voltage. The confusion arose from treating the generator as a single-phase device rather than recognizing it as a three-phase machine. This misunderstanding led to incorrect calculations for full load current and voltage regulation. Correctly applying the three-phase formula resolves the issue and provides accurate results.
sandy.bridge
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Hey all,

If we are given a synchronous generator with the following nameplate values 10MVA, 13.8kV, 2 pole, 60 Hz

why is it not sufficient to go
S_{RATED}=I_{RATED}V_{RATED}

as we did for transformers?

My reason for asking is because I am trying to determine the voltage regulation of a particular generator. However, if I determine the full load current using the above formula, I get an absurd result.
 
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Is the generator a 3 phase machine? If so, the apparent power = √3 Voltageline ⋅ Currentline.
13.8kv is a line voltage.
 
How silly of me. Honestly, this entire time my issue was that I did not divide S by three. Thanks!
 

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