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Yin<br><br>
See<br>
<a href="http://users.tpg.com.au/t_design/PCL_Design/PCL_Design.htm" eudora="autourl">
http://users.tpg.com.au/t_design/PCL_Design/PCL_Design.htm</a><br><br>
Graham Morrison<br><br>
<br>
At 01:07 AM 16/09/2009, Yin Hang wrote:<br>
<blockquote type=cite class=cite cite="">--===============0736645340==<br>
Content-Language: en-us<br><br>
Hello,<br>
Thanks for your replying.<br>
I have connected connect the output of the controller to its<br>
"input control function" (input 4).<br>
But if you look at the example in TRNSYS - "DHSW", you
will<br>
also find this fluctuation problem.(suddenly on and suddenly<br>
off, even still in the deadband).<br>
Thanks.<br>
Yin<br><br>
-----Original Message-----<br>
From: Francois Badinier<br>
[<a href="mailto:francois.badinier@icax.co.uk" eudora="autourl">
mailto:francois.badinier@icax.co.uk</a>]<br>
Sent: Tuesday, September 15, 2009 5:11 AM<br>
To: 'Yin Hang'; trnsys-users@cae.wisc.edu<br>
Subject: RE: [TRNSYS-users] problem about the differential<br>
controller (Type2)<br><br>
Yin,<br><br>
Make sure you connect the output of the controller to its<br>
"input control function" (input 4). You link the
controller<br>
with itself basically. This has to be done in order to get<br>
the hysteresis effect working (influence of the previous<br>
state).<br>
With that done, it should work properly.<br><br>
Regards,<br><br>
François Badinier<br>
Development Engineer<br>
ICAX Ltd<br>
1 Hatfield House<br>
Baltic Street West<br>
London EC1Y OST<br>
francois.badinier@icax.co.uk<br>
<a href="http://www.icax.co.uk/" eudora="autourl">www.icax.co.uk</a><br>
<br>
<br><br>
<br>
-----Original Message-----<br>
From: Yin Hang
[<a href="mailto:yhang@purdue.edu" eudora="autourl">
mailto:yhang@purdue.edu</a>]<br>
Sent: 14 September 2009 19:47<br>
To: trnsys-users@cae.wisc.edu<br>
Subject: [TRNSYS-users] problem about the differential<br>
controller (Type2)<br><br>
Hello,<br>
I have a problem when I use differential controller type2.<br>
For example, I want to control my solar collector loop pump<br>
by using one of this controller.<br>
My control logic is when the outlet temperature of my solar<br>
collector is higher than the inlet temperature of my solar<br>
collector 4C, the pump will be on;<br>
And when it is lower than the inlet temperature for 2C, the<br>
pump will be off.<br>
However, I found the output control signal is fluctuated,<br>
such as it suddenly becomes off even the outlet temperature<br>
is 2C higher than the outlet temperature; and next timestep,<br>
it suddenly on.<br>
Could you help me to fix this problem? I figure it is really<br>
bad since it is un-normal for my pump during true situation.<br>
Thanks.<br><br>
<br><br>
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<br>
Graham Morrison<br><br>
Emeritus Professor of Mechanical Engineering<br>
School of Mechanical & Manufacturing Engineering<br>
The University of New South Wales<br>
Sydney Australia 2052<br><br>
Phone +61 (0) 2 9385 4127<br>
Mobile +61 (0) 425 212 218<br>
Fax +61 (0) 2 9663 1222<br><br>
g.morrison@unsw.edu.au<br><br>
Web sites<br><br>
<a href="http://www.mech.unsw.edu.au/content/staff/morrison.cfm?ss=4">
G.</a>
<a href="http://www.mech.unsw.edu.au/content/labs_computing/Solar_Thermal.cfm?ss=5">
Morrison<br><br>
Solar Thermal Energy Laboratory at
</a>
<a href="http://www.mech.unsw.edu.au/content/labs_computing/Solar_Thermal.cfm?ss=5">
UNSW<br><br>
</a><a href="http://solar1.mech.unsw.edu.au/">Solar thermal
technology</a><br><br>
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