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Line-Earth Voltage in 3Phase unbalance loads 6

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MAZ13

Electrical
Apr 21, 2011
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Hi all,

If we have a 3phase unbalance load (400V L-L, 230V L-N nominal voltages), which all loads are on 1phase and the other phases are unloaded, is it expected that L-E voltage in unloaded phases changes? (anything rather than 230V?)

I know that by unbalance loading, neutral point displaces and neutral voltage is something rather than 0. Therefore I expect L-N voltage changes on all phases. But my question is about line to earth voltage.
I ask this question because software simulation of such unbalanced load by DIgSILENT power factory shows such strange results!
 
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For the 5-conductor cable side VL1E it is the bus voltage Va minus one-time VN and VL1N it is Va minus two times VN.
VL2E=VL2N and VL3E=VL3N
However, the accurate calculation it has to be done in complex.

 
I'm sorry, my mistake! According to my definition V2E = VR-0 [ground], so V2E ≠ V2N [same as V3E]. This means that V2E and V3E are nonsense. Also, basically, V2N and V3N are not usable.
 
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