3 phase wye wye delta R C L circuit

Discussion in 'Homework Help' started by de_rock, Mar 22, 2009.

  1. de_rock

    Thread Starter New Member

    Mar 22, 2009
    2
    0
    Ok well i am having troubles with question 5 i have a pretty huge test tommorow, and was hoping somebody could help me out just click on the attachment and take a gander.

    Thanks
     
  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    5,448
    782
    Perhaps show how far you have got with your answers on this - it's a lot of work for someone to do without first seeing your attempt.
     
  3. de_rock

    Thread Starter New Member

    Mar 22, 2009
    2
    0
    Yea i realize it is kind of alot of work but even just the formulas needed would be a ton of help.
    my Professor told me this is on the test and the internet has for some reason not worked out for me this time.
     
  4. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    5,448
    782
    OK - I'll just give my method for RMS current magnitudes only. I'll use the notation |I| to indicate the magnitude of I.

    3-phase loading is balanced so all line currents balance.

    For IR:

    |IR|=(Vline/√3)/R where Vline = 440V

    For IXC1:

    |IXC1|=(√3 x Vline)/Xc where Xc=1/(ωC)

    For IXC2:

    |IXC2|=Vline/Xc

    For IXL:

    |IXL|=(Vline/√3)/XL where XL=ωL

    For I2:

    |I2|=||IXC1|-|IXL||

    i.e. subtract the reactive current terms since they are in anti-phase

    For IT:

    |IT|=√(|IR|^2+|I2|^2)

    i.e. vector addition of real and reactive current values.

    Hope that's of some help. I'll leave the rest to you.
     
  5. Jennifer

    New Member

    Mar 23, 2009
    3
    0
    was that of any help to you? I haven't quite gotten to motor controls yet, but that is where I'm heading. He gave you the formula to work the problem out. Good luck on your test.
     
Loading...