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Apply line-to-line voltage to EMD Synchrnous Motor

Builder
Builder

Hi,

 

In EMD library, the source inputs of the sychrnous motor (for example, PMSM) are line-to-neutral voltages. In reality, if there are three power leads coming from the motor windings, the three phase source connected to the leads are line-to-line quantity. So I am wondering if it is possible to apply line-to-line voltage to the model.

 

Thanks,

Kan

2 REPLIES 2

Re: Apply line-to-line voltage to EMD Synchrnous Motor

Siemens Valued Contributor Siemens Valued Contributor
Siemens Valued Contributor

Hi kan,

In the EMD library, all 3 phase motor models take as input electric potential. Fom this we derive:

  • the line to line voltage as the potential difference between 2 lines.
  • the phase voltage as the potential difference between the input and the output of a phase (UsA,UsB,UsC).

Now depending if the motor is star or delta connected, we have the following relation:

Star:

StarConnection.png

Line to line voltage = sqrt(3) * phase voltage (phase voltage in star is also called line to neutral voltage)

Line current = phase current

Delta:

DeltaConnection.png

Line to line voltage =  phase voltage

Line current = sqrt(3) * phase current

 

I would say it is up to you to provide the correct potential to your machine based on those relations.

Best regards,

Florent

Re: Apply line-to-line voltage to EMD Synchrnous Motor

Builder
Builder

Hi fpasteur,

 

Thanks for your explanation.

I fully understand the relationship which is applicable to sinusoidal case. However, when going to nonlinear case, I think the phase voltage might not be sinusoidal anymore even the line-to-line voltage is sinusoidal. 

 

Kan