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Generator complex Impedance explanation

Generator complex Impedance explanation

Generator complex Impedance explanation

(OP)
Could you please point out a good textbook or reference book which explains all the following impedances for synchronous generators? Please explain as much as you can.

1) Direct-axis unsaturated synchronous reactance (Xd)
2) Direct-axis unsaturated transient reactance (Xdi')
3) Direct-axis unsaturated subtransient reactance (Xdi'')
4) Direct-axis saturated transient reactance (Xdv')
5) Direct-axis saturated sub-transient reactance (Xdv'')
6) Quadrature-axis unsaturated synchronous reactance (Xq)
7) Quadrature-axis unsaturated transient reactance (Xqi')
8) Quadrature-axis unsaturated subtransient reactance (Xqi'')
9) Negative-sequence unsaturated reactance (X2)
10)Zero-sequence unsaturated reactance (X0)
11)Negative-sequence saturated reactance (X2v)
12)Zero-sequence saturated reactance (X0v)
13)Potier reactance (Xp)
14)Leakage reactance (Xl)
15)Positive sequence resistance (R1)
16)Negative sequence resistance (R2)
17)Zero sequence resistance (R0)
18)Stator resistance per phase (Ra)
19)Rotor resistance (Rt)
20)Direct-axis transient unsaturated open-circuit time constant (Td0')
21)Direct-axis transient unsaturated short-circuit time constant (Td')
22)Direct-axis subtransient unsaturated open-circuit time constant (Td0'')
23)Direct-axis subtransient unsaturated short-circuits time constant (Td'')
24)Quadrature-axis transient unsaturated open-circuit time constant (Td0')
25)Quadrature-axis transient unsaturated short-circuit time constant (Td')
26)Quadrature-axis subtransient unsaturated open-circuit time constant (Td0'')
27)Quadrature-axis subtransient unsaturated short-circuits time constant (Td'')
28)Unsaturated short-circuit time constant of armature winding (Tz)

RE: Generator complex Impedance explanation

First, not all of these are impedances. Some are time constants.

I would assume this is a larger generator to have all these values listed. Many smaller ones don't.

There are several good books, but depending on what you are doing, you probally don't most of these.

You would get more help on Electric power & Transmission.

What is your area of concern? Protection, stability, planning?

RE: Generator complex Impedance explanation

Honestly, where have you even tried looking?  

Try Analysis of Faulted Power Systems by Anderson, or just paste each term into Google.

You need to at least make some effort of your own rather than expecting someone to spoon feed it to you.  

Is this a homework problem?



 

RE: Generator complex Impedance explanation

(OP)
You all guessed it right. I am doing the stability studies. Of course, I might not need to know everything that I listed.

I deal with a small isolated system. Every governor action, ever exciter action and many other things have a big impact on the small system. I am trying to model the generator, governor and exciters in a detailed manner.

These values are present in each generator system. We just don't understand them. I am sick of fully not understanding it. I have tried so many books (from Dr.Kundur's to Blackburn's book). They covered some of those but not all. Basically, I havn't found the holy grail yet. If you have found one, please let me know.

DPC, I wish this is just a homework problem. :) I haven't read the book that you recommended. Will it provide me with what I need?
 

RE: Generator complex Impedance explanation

There are some standard IEEE models for machine response which would be worth finding if you are trying to model them.

A while ago I uploaded an old CEGB document on generator capability charts which might be of interest. The links from edison123 are still alive: thread238-255286: Operating Curves For generators
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: Generator complex Impedance explanation

Probably not quite enough for stability studies, but it will help in understanding Park's Transformation and the DQ0 reference system that is the basis for most of these constants.  The Standard Handbook for EE (Fink & Beatty) has a reasonable amount of information.

I don't think you are going to find the holy grail.  There is a lot of similarity in the constants and once you have a basic understanding of the reactances and time constants, the meaning of a lot of them can be inferred.  

You should have no problem finding explanations for the basic reactances - sub-transient, transient and synchronous.  



There are also standard IEEE models for governors and voltage regulators.  

 

RE: Generator complex Impedance explanation

A good book, but not for what you're looking.  Focuses a lot of voltage transients/surge, but not on swing angle transients.  The section on generator modeling (11.2) is only 5 or 6 pages wrong and touches very few if any of parameters mentioned above.

=====================================
(2B)+(2B)'  ?

RE: Generator complex Impedance explanation

typographical error alert:

5 or 6 pages wrong
should've been:
5 or 6 pages long

lol
 

=====================================
(2B)+(2B)'  ?

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