Operating Curves For generators 7

[jan63]

I want to draw operating curves for gen which will determine the max out put f the gen keeping in view the temperatures f stator and rotor and also the satbility limit of the gen is not crossed.Can some one give me an easy way as the books description is a lengthy one

 

[jan63]

Thankyou.I have got it.

 

[EddyWirbelstrom]

Operating performance of the synchronous machine and asynchronouse machine.

Betriebsverhalten der Synchronmaschine und Asynchronmaschine

http://www.et5.tu-harburg.de/Lehre/Praktikum/Grundlagen_Praktikum/PDFs/V19.pdf

 

[wolf39]

Hi Scotty:

It will be my pleasure to give you this information. However, due to heavy work load, I've to ask for a little bit of patience.

Regards

Wolf

http://WWW.HYDROPOWER-CONSULT.COM

 

[wolf39]

Hi folks:

Thanks for the patience.

Attached please find a method how to design a turbo generator (cylindrical rotor design) capability chart (Attachment I). It seems that it is not possible to place two attachments to one post. The second attachment will therefore be sent separately.

In case there is an interest, I can work out a capability chart design for a hydro generator (salient pole design) as well.

Best regards

Wolf
WWW.HYDROPOWER-CONSULT.COM

 

[wolf39]

Folks:

Here is my second attachment.

Regards

Wolf
WWW.HYDROPOWER-CONSULT.COM

 

[ThePunisher]

Hi everybody, this thread is very interesting.

scotty, do you still have that CEGB document online? I tried the link but I guess the sharepoint is expired.

Wolf39, is the procedure your posted applicable to diesel generators and GTGs as well?

 

[wolf39]

ThePunisher:

The procedure I issued is valid only for synchronous generators with cylindrical rotors. GTGs and fast running Diesel generators are falling into this category. Low speed Diesel generators with higher outputs, however, usually are equipped with salient poles, like hydro generators. To design a performance chart for this type of design is possible but more complicated. It seems that there is very little interest for such chart since there was no reaction expressed in the forum after I posted the other procedure last month.

Regards

Wolf

http://www.hydropower-consult.com

 

[ThePunisher]

So does it mean that I can use the same procedure for diesel generators 1000ekW and less? If you say slow speed, at what RPM are we talking about?

We have a large 3.74MW, 5.5MVA, 0.68 P.F. with a max kVAR = 4.45MVAR, 900RPM, Diesel generator. We have data for generator impendances and time constants. I am hoping you have something that couild help us at least construct this geenrator's capability curve since we are no longer able to contact the manufacturer for no apparent reason from the client.

 

[wolf39]

ThePunisher:

If you read my posts carefully, you will find all the information you've asked for.

Regards

Wolf

http://www.hydropower-consult.com

 

[ScottyUK]

Ok, it's back on Rapidshare for a while. Roughly 10MB compressed.

http://rapidshare.com/files/311035705/CEGB_Generator_Performance_Chart.rar.html

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

 

[ThePunisher]

Thanks scotty,

Sure this will be great info! Thanks wolf39 for the curve plot.

 

[rovineye]

wolf39,
I for one have slow salient pole generators. From what I remember the difference between the files you uploaded (which are great by the way) is that there would be a difference in the underexcitation limit, since it could be running for a while with no (or reverse) excitation. If you have any info I that I would be interested.
Thanks

 

[ScottyUK]

Hi Wolf,

If I remember my machine theory correctly a salient pole machine typically has a much greater capability to absorb reactive power than a turbo machine. I'd be interested in seeing how you develop a capability chart for a hydro machine, I haven't done much with salient pole machines because of the relative lack of hydro machines in the UK and I'd be interested to learn. Sorry if silence came across as dis-interest.


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

 

[esee135]

...the modern adopted method is there is no under-excited limit on the S-base circle for hydro-gen. To form the underexcited lower region you set the UEL limits with a margin to coordinate around the LOE-40 relay.

The underexcited zone becomes a question of bus voltage stability during the cap-curve test. The unit can run within a +/-5% variation of Vt for the given capability curve. Larger changes rescales the curve by the ratio of Vt/Xd against the base vector (Vt+IsxjXd = Ef)

Generally during underexcitation the stray flux tends to exit more perpendicular to the core laminations at the end-arms, hence the step back design of the top 3 and bottom 3 stator lamination stacks.

I've ran fully underexcited with good terminal voltage and with infra-red on a hydro, there were no heating concerns. In contrast, I have also ran another unit at ~ 70degrees rotor angle underexcited with a low bus voltage, and at that region a stability limit can exist.

UEL testing is the definitely the harder part of cap-curve testing.