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Dear Adrien,<BR>
<BR>
I have seen in example PID-Cooling-Flowrate that the control signal is used to modulate the cold-side flowrate; so I think it can be used in this way.<BR>
<BR>
In my model, I don't understand why the outlet temperature ( first of all the outlet flowrate) from the collector has such big oscillations and it 's not fixed at 280°C.<BR>
<BR>
Any advices are accepted. Thanks.<BR>
<BR>
<BR>
<BR>
<BR><BR>> Date: Wed, 2 May 2007 17:05:23 +0200<BR>> From: a.jezequel@itf.biz<BR>> To: ozzysam@hotmail.com<BR>> CC: trnsys-users@engr.wisc.edu<BR>> Subject: Re: [TRNSYS-users] Request<BR>> <BR>> Dear Samuel,<BR>> <BR>> If you see the example concerning the use of PID, you will see that the <BR>> PID output 1 ('control signal') is defined as an energy (in kJ/hr) used <BR>> to heat or cool the building. So I think that you have to adapt the PID <BR>> output with an equation to obtain a fluid flow rate.<BR>> <BR>> I think that tPiD only give the energy rate necessary to maintain the <BR>> controled variable at the setpoint.<BR>> <BR>> Maybe you can have a look at this example in "feedback control" to see <BR>> how are used PID.<BR>> <BR>> I am not really sure of what I say, so if someone is able to confirm or <BR>> to cancel what I said, he's welcome...<BR>> <BR>> Best regards,<BR>> <BR>> Adrien<BR>> <BR>> Samuele a écrit :<BR>> > Dear all,<BR>> > <BR>> > I'm trying to build a model in which there are a variable speed pump <BR>> > and a linear parabolic concentrator: I'm using a pid controller to <BR>> > regulate the inlet flowrate for the liner parabolic concentrator <BR>> > because I need that the outlet temperature from the concentrator is <BR>> > costant ( 280°C).<BR>> > <BR>> > I have seen the result but I don't know if it's working well. There is <BR>> > the file.tpf enclosed.<BR>> > <BR>> > Could anybody tell me if anything is wrong?<BR>> > <BR>> > Thanks in advance.<BR>> > <BR>> > ------------------------------------------------------------------------<BR>> ><BR>> > _______________________________________________<BR>> > TRNSYS-users mailing list<BR>> > TRNSYS-users@engr.wisc.edu<BR>> > https://www.cae.wisc.edu/mailman/listinfo/trnsys-users<BR>> > <BR>> <BR>> -- <BR>> <BR>> ***************************************************************<BR>> Adrien JEZEQUEL <BR>> Ingénieur en Simulations Dynamiques<BR>> ITF (Ingénierie Tous Fluides)<BR>> 87, route de Chambéry<BR>> 73230 ST ALBAN EN LEYSSE<BR>> FRANCE<BR>> Tel: 04.79.75.00.29<BR>> Website: www.itf.biz<BR>> Mail : a.jezequel@itf.biz<BR>> <BR>> <BR><BR><br /><hr />Explore the seven wonders of the world <a href='http://search.msn.com/results.aspx?q=7+wonders+world&mkt=en-US&form=QBRE' target='_new'>Learn more!</a></body>
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