3 Phase Electric Power Question

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tomizzo
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I have a question and am wondering if reddit can help. In a 3 phase power system, the overall total power is meant to remain constant. Now, I understand that the individual powers are meant to vary, but as a system, it is supposed to be a constant. If you could take a look at this "code" if you wish that I've created in Mathematica, it is apparent that the power is time varying. I must be doing something wrong, any help?

Mathematica code defining three 20-volt cosine voltages at 377 rad/s with 120 degree phase shifts, resistances R1=5, R2=4, R3=2, and a total power function; below are plots of the three voltages and a plot of the total power, which varies with time between about 140 and 240.
 
...but as a system, it is supposed to be a constant.

Are you sure that statement is true for unbalanced system?

I know nothing of 'Mathematica" , but suggest you test your code by setting all three resistors equal...
 
jim hardy said:
Are you sure that statement is true for unbalanced system?

I know nothing of 'Mathematica" , but suggest you test your code by setting all three resistors equal...

I see. You sir are correct. I completely forgot about the fact that three different line impedances would put the system out of balance. I set the impedance values to be equal and of course, the power remained constant.

Thanks a lot Jim!