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Frequency response test

asked 2018-09-18 00:17:47 -0600

Hamid gravatar image


I have a frequency step test, dynamics study.

In Power World, one is able to simulate a frequency step test by changing the frequency at the slack generator.

In PSS/E, I couldn't find an equivalent 'disturbance' to emulate a frequency step test. The closest I found is the GRef, but I understand that changes the Pmech of a generator directly, instead of emulating a frequency step change. Is this correct? Or does PSS/E have a frequency step function similar to Power World?

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answered 2018-09-18 04:12:33 -0600

perolofl gravatar image

You can use generator model PLBVFU1 at a selected generator in order to simulate that kind of frequency step test.

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Hey. Im using the student version PSS/E 34. I have noticed i do not own this model in the library, although it is in the model manual. Am i missing something ? If not, how can i import the model, and where is it avaiable.

Diogo Carrilho gravatar imageDiogo Carrilho ( 2020-05-06 12:39:06 -0600 )edit

Model PLBFU1 was added in rev 34.1.

perolofl gravatar imageperolofl ( 2020-05-07 03:30:49 -0600 )edit

I found out i had to import first the dyr file and then the model happear as a generator.

Diogo Carrilho gravatar imageDiogo Carrilho ( 2020-05-07 11:42:46 -0600 )edit

answered 2018-09-18 06:30:59 -0600

Hamid gravatar image

Thank you for the answer; it looks like that model is to 'play in' field-measured signals, rather than force a frequency step for the generator I'm trying to simulate, is that correct?

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The model is general and can handle any curve form, for example a measured frequency. A step test is a very simple "curve", with just a few data points. The needed .plb file is thereby very simple to construct in a file editor.

perolofl gravatar imageperolofl ( 2018-09-18 09:54:16 -0600 )edit

Many thanks;what I mean is,this will only graph what was gathered in the field right?What I'm trying to do is this:I have modeled a generator,G1,with models GENTPJU1/ESST4B/WSIEG1,and a slack gen.I want to now make a system frequency step change and simulate G1's gov response. Would PLBVFU1 do this?

Hamid gravatar imageHamid ( 2018-09-19 23:41:33 -0600 )edit

Use PLBVFU1 at your slack generator. This will force a step change in the system frequency and G1 will respond to the changed frequency.

perolofl gravatar imageperolofl ( 2018-09-20 00:54:07 -0600 )edit

Many thanks; the manual, however, says: "PLBVFU1 model must be attached to this generator with the following conditions: Vscheduled =Vinitial of the bus, generator Pgen = 0.0, and generator QMAX=QMIN=0.0." How can the slack gen have Pgen=0 and Qmax/min=0?

Hamid gravatar imageHamid ( 2018-09-21 22:45:34 -0600 )edit

Add a load at the bus with (negative) P and Q cancelling the generator power.

perolofl gravatar imageperolofl ( 2018-09-22 00:20:10 -0600 )edit

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Asked: 2018-09-18 00:17:47 -0600

Seen: 944 times

Last updated: Sep 18 '18