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Parrallel motor cables in trefoil, phase formation.

Parrallel motor cables in trefoil, phase formation.

Parrallel motor cables in trefoil, phase formation.


In a 4x cables pr. phase system, how would you create the most symmetrical formation create a minimum of current unbalance?

With 4x cables pr phase it seems impossible to create 100% symmetry.

My solution would be this setup:

Where each phase i rotated 1 turn clockwise for each new trefoil.

Thanks in advance

RE: Parrallel motor cables in trefoil, phase formation.

Hello, thank you for the answer.

I've seen the ABC ABC ABC recommendations in many places, but i suspect it is the general recommendation because it is easy, and it will almost always be a sufficient formation.
Although the ABC ABC ABC formation should be sufficient, I'm wondering if the solution with clockwise rotated phase formation is better.
If it is better i see no reason to not create a more balanced drive supply.

Thanks in advance

RE: Parrallel motor cables in trefoil, phase formation.

Hi we have this in our National Standard (equivalent to IEC I believe). Since your stated goal is maximum reduction of current imbalance you should follow table D1.

The ABC ABC etc configuration is only for when your cable spacing is such that the influence of the magnetic fields no longer overlaps (significantly) and therefore there is no interaction.

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