User-agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:8.0) Gecko/20111105 Thunderbird/8.0
Wang,
You should already have the source code for the PID controller in
..\TrnsysXX\SourceCode\Types\. I would also recommend reading the
Type23 section of the 04-MathematicalDescription manual.
PID controllers can operate in one of two ways: they can generate
a greater signal value if the sampled input value is below the set
point or they can generate a greater signal value if the sampled
input is above the current set point. Imagine a heating application
with a PID controller. As the zone temperature falls, you want the
PID to give you a bigger and bigger signal. Now imagine a cooling
application. As the zone temperature rises, you want the PID to give
you a bigger and bigger signal. You may have to add an equation
after the PID to invert its control signal if it is acting the
opposite of the way that you want.
David
On 11/14/2011 04:28, wangyang wrote:
Dear all,
I have a question about PID controller in TRNSYS for its
developer.
Which expert knows PID controller in TRNSYS developer? Or
Which expert could pass me the source code of PID controller or
its internal algorithm etc.? I guess PID controller in TRNSYS is
based on empirical equation or iterative algorithm. Since there
is very weird
simulation results i.e. I set the set point CO2 concentration
1000 ppm as PID controller's set point; its control signal links
to Opening Factor (OF) of windows; indoor CO2 concentration
links to PID's controlled variable. However, when indoor CO2
concentration is less than set point 1000 ppm, PID begins to
activate OF i.e. windows are open. But based on PID principle,
as we know, if CO2 concentration is not getting to set point
1000 ppm, at this time windows are open will result in the ERROR (between the
set point and actual indoor CO2 concentration) increasing. So I'm puzzled! Please PID controller in
TRNSYS developer or other experts explain this weird
phenomenon!
When replying, please edit your Subject line so it is more
specific
than "Re: Contents of TRNSYS-users digest..."
Today's Topics:
1. Re: (no subject) (David BRADLEY)
2. Re: TRNSYS3D Shading on Walls? (David BRADLEY)
3. Re: how to identify a wall that is adjacent two walls
(David BRADLEY)
4. Error in reading type 51 external performance File
(Walif M'kacher)
---------- 已转发邮件 ----------
From: David BRADLEY <d.bradley@tess-inc.com>
To: Erik Boschek <erikboschek@yahoo.com>
Date: Fri, 11 Nov 2011 12:01:47 -0600
Subject: Re: [TRNSYS-users] (no subject)
Erik,
You are right on with all three of your points. For
reference, we discontinued use of Type109 in Trnsys17 in
favor of option 2 (Type15), which is correct from an energy
perspective even though it isn't a smooth curve. In gernal
think that a control strategy that relies only on the
instantaneous DNI as its input might run into trouble not
only in simulation but also in the real world; clouds pass
in front of the sun rapidly sometimes. While I won't pretend
that the "spiky" profile that Type15 generates is totally
realistic, I think it is a fairly accurate representation of
DNI. Bear in mind that Type15 is trying to reconstruct a
minute by minute radiation profile based only on 1 number
and to do so correctly for all possible climate types. You
might consider a control strategy that uses the output of
Type15 but put through a running-average component so that
your control decisions are based on a somewhat more stable
(smoother) profile.
Best,
David
On 11/11/2011 00:32, Erik Boschek wrote:
Dear TRNSYS users,
I have a simple question regarding weather reading
and interpolating direct normal radiation (DNI) values
for time steps less than an hour.
As long as I have been using TRNSYS (using TRNSYS
16.1) I have understood this can be done in a few ways
as follows, including the consequence for an example
TM2 file (see attached screen shot for clarification):
1.) Do not interpolate, using Type 15 with output
DNR (not interpolated): you end up with a "steppy"
profile
2.) Using Type 15, but with 2-axis tracking and the
output "Beam radiation for surface": you get a
discontinuous "spikey" profile, but the integration of
energy across the hour is respected
3.) Same as 2, but using Type109-TMY2: You get a
smooth profile, but often there appear inexplicable
spikes at the beginning or end of the day. The one in
the plot obviously is an extreme case.
For reference: I just used the Daggett profile
"US-CA-Daggett-23161.tm2" which came with TRNSYS, but
the behavior is not specific to this file.
Generally, I have been using 2, but it can cause
problems if there is, for example, some triggering
function based on DNI and the DNI hovers around the
threshold. Is there another option for getting a
smoother profile or is it best just to not
interpolate? Any opinions? Feel free to point me to an
earlier post on this topic in case I missed it.
---------- 已转发邮件 ----------
From: David BRADLEY <d.bradley@tess-inc.com>
To: Marion Hiller <hiller@transsolar.com>
Date: Fri, 11 Nov 2011 12:03:16 -0600
Subject: Re: [TRNSYS-users] TRNSYS3D Shading on Walls?
TRNSYS-users,
My apologies; my reply to Graham was incorrect; as Marion
says, only the windows are affected.
Kind regards,
David
On 11/11/2011 01:33, Marion Hiller wrote:
Graham,
the shading defined in Trnsys3D effects only windows.
Marion
Dipl.-Ing. Marion Hiller
TRANSSOLAR: KlimaEngineering - Technologien für
energieeffizientes Bauen
und Nutzerkomfort in Gebäude
Munich - New York - Stuttgart + 49.711.67976.0
Transsolar Energietechnik GmbH, Curiestrasse 2, 70563
Stuttgart
Amtsgericht Stuttgart - HRB 23347, Steuernummer 99073/00911,
USt-IdNr.:
DE152272639
Geschäftsführer: Dipl.Ing. Matthias Schuler, Dipl.Ing.
Thomas Auer,
Dipl.Phys. Stefan Holst, Prof. Dipl.-Ing. Bleicher
-----Ursprüngliche Nachricht-----
Von: Graham Linn [mailto:grahamjlinn@gmail.com]
Gesendet: Donnerstag, 10. November 2011 21:49
An: trnsys-users@cae.wisc.edu
Betreff: [TRNSYS-users] TRNSYS3D Shading on Walls?
Hello TRNSYS users,
I have a question about shading in TRNSYS3D. Does a shading
object
affect how much insolation hits the entire building or just
the
windows on the building?
--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI 53703 USA
---------- 已转发邮件 ----------
From: David BRADLEY <d.bradley@tess-inc.com>
To: Nidal Abdalla <nidalabdalla@yahoo.com>
Date: Fri, 11 Nov 2011 12:29:48 -0600
Subject: Re: [TRNSYS-users] how to identify a wall that is
adjacent two walls
Nidal,
You have to be a little careful here. If you have a wall
in zone 1, half of which is adjacent to zone 2 and half of
which is adjacent to zone 3, you actually need to draw the
wall as two walls in zone 1. Trnsys3D requires the user to
be quite vigilant about manually setting adjacencies. You
need to draw the ADJACENT wall in both zones and you need to
open the object window for each of them, set the
construction to ADJ_WALL, set the "outside boundary
condition" to "Zone" and then manually select the zone to
which it is adjacent in the "outside boundary object" field.
If you have been very careful about drawing your ADJACENT
walls so that they have exactly the same verticies in both
zones to which they belong, you can then select the menu
item: Plugins: Trnsys3d: Surface Matching and click the
"match in entire model" button.
Kind regards,
David
On 11/11/2011 08:32, Nidal Abdalla wrote:
I drew a house using Trnsys3d
that consists of: 3 bed rooms, living room, guest
room and bath . The house was divided into 6 zones.
Wall_zone5, for example, is adjacent two walls for
two different zones. I am wondering how to identify
a wall (using Object Info) that is adjacent two or
more walls of diff. zones.