RE: modelling a montroller

[Michaël Kummert <kummert@xxxxxxxxxxxxx>]

Timo,

There is a free but non-supported PID controller on the TRNSYS website
(http://sel.me.wisc.edu/trnsys , choose TRNLIB, go to the bottom of the page
and choose "controllers").

TRANSSOLAR also sells a (supported) PID controller Type
(http://www.transsolar.com)

I am not sure to understand the rest of your question, but may be you could
have a look to Type 93 (input value recall).
That Type will "remember" the value of its inputs for some time steps.

Cheers,

Michaël

_________________________________________________________

Michaël Kummert

Solar Energy Laboratory - University of Wisconsin-Madison
1303 Engr Res Bldg, 1500 Engineering Drive
Madison, WI 53706

Tel: +1 (608) 263-1589
Fax: +1 (608) 262-8464
E-mail: kummert@engr.wisc.edu 

SEL Web Site: http://sel.me.wisc.edu 
TRNSYS Web Site: http://sel.me.wisc.edu/trnsys



> -----Original Message-----
> From: owner-trnsys@relay.doit.wisc.edu 
> [mailto:owner-trnsys@relay.doit.wisc.edu] On Behalf Of Timo Sengewald
> Sent: Thursday, November 07, 2002 09:52
> To: TRNSYS group
> Subject: modelling a montroller
> 
> 
> Hello!
> 
> I'm doing my diploma thesis about a TRNSYS simulation of a 
> solar heating system. My problem is to control all the flow 
> rates that occur. The standard differential controller 
> shipped with TRNSYS is not an appropriate solution. Is there 
> another possibility (e.g. by using equations) to model a 
> PID-controller than creating (or buying) a new controller 
> type ? Another question concerning my controller problem is 
> if it's possible to link the output of an equation with one 
> of its inputs by defining an initial value for this input? I 
> want to calculate a control signal which depends on the 
> control signal of the last step. Of course TRNSYS did not 
> know about the output which is also the input of the equation 
> and did not start.
> 
> Thanks a lot in advance
> 
> Timo
> 
>