PROCESS CONTROL PRACTICES, PROJECT 1
TABLE OF CONTENTS
1.0 ABS ABSTR TRACT ACT...................... ................................................2 ..........................2 2.0 METHODOLOGY........................................3 3.0 RESULT AND CALCULATION......................5 4.0 DISCUSSIO DISCUSSION.................... N...........................................11 .......................11 5.0 CONCLUSION..........................................15
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PROCESS CONTROL PRACTICES, PROJECT 1
1.0 ABSTRACT The objective of this report is to know the details about the process control simulation that use in industry nowadays. Besides that, one of the major objective in this report is to apply knowledge that have learns. The method to get the exact value of optimum optimum tuning also studied. In this report, report, various various method of tuning is being practice in order to get exact value for optimum tuning. Every changing of value was recorded in order to get optimum value of tuning. In search for the optimum ,I ,I and ! values ,several techni"ues are used by using reformulated tangent method. #or this report, to get the value for response rate $%%&, dead time $Td& and time con stant $Tc& $Tc& was calculated by using reformulated tangent method.
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PROCESS CONTROL PRACTICES, PROJECT 1
2.0 METHODOLOGY
Flo E!"#$%&'( FIC 31 Open Loop Test
'. The process process was was let to to stabili(e stabili(e either either manually manually or automati automatically cally.. ). The cont control roller ler was set to manual manual mode. mode. *. The manipulated manipulated variable variable $+& $+& value of the the controller controller was initially initially set set to *- and the set point point was set to /.0m*1h. 2. The proces processs was was let let to to stabil stabili(e i(e.. -. The + + value value of the control controller ler was increased increased by 2. 3. The process process variable variable was let let to response response for for about - 4 '/ seconds seconds to to let it become become stable. stable. 5. The + value value of the control controller ler was decreased decreased back by the the value of the the increment increment in step step -. 0. 6tep - to 5 was repeate repeated d by using using + value value increment increment of 0 and and '). 7. The graph graph obta obtained ined was printe printed d out. out. '/. 8alcul 8alculati ation on was made by referr referring ing to the printed printed graph in order order to obtain obtain the respons responsee rate rate $%%&, dead time $Td& and time constant $Tc& for each value of +. ''. Tuning Tuning rules9 rules9 a. : cont control rol mode mode of I! I! was was used used for flow flow cont control rol.. b. The proportional band $B&, controller gain $; 8& and integral time $I& was calculated using 8ohen<8oon tuning rules e"uation. c. The B, ;8 and I were calculated using the %%, T d and Tc that is obtained from the open loop test. d. The B, ;8 and I were recorded.
SP Test and Load Disturbance Test
'. The B and I value value were set set to the the value calcul calculated ated in the the open loop loop test. test. Page 3
PROCESS CONTROL PRACTICES, PROJECT 1 ). The contr controll oller er was was set to automa automatic tic mode. mode. *. The process process variab variable le was let to respon response se until until it became became stable stable or it oscilla oscillates tes at a constan constantt 2. -. 3. 5.
magnitude. The cont control roller ler was set to manual manual mode. mode. #or load disturb disturbance ance test, test, the + value of the the controller controller was was increased increased by -. -. :fter * seconds, seconds, the controll controller er was set to to automatic automatic mode. mode. %epeat %epeat the the steps steps for each each + value. value.
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PROCESS CONTROL PRACTICES, PROJECT 1
3.0 RESULT AND CALCULATION
Result A: FIC31 OPEN LOOP TEST
!ata, =+ > 2, Ѳ > -//
a>
>
b>
>
Response Rate,RR
%%>
.
>
.
6.0 mm
> **./) 1min
1 min
Dead Time,Td
Td$time& > Td$length& x b
'.- mm x
> /./) min Time Constant,Tc
Tc$time& > Tc$length& x b
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PROCESS CONTROL PRACTICES, PROJECT 1
*./ mm x
> /./2- min
Table Table 3b) Tuning Rules by Cien Ci en , !rones " Res#ic$ %C!R)
B $& > '35 %%Td %%Td
I > Td
'35 $**./)&$/./)& > ''/.)7
; 8 >
> /./) min
> /.7/5 > /.7'
CLOSED LOOP TEST
6ET ?I@T TE6T $6&
A?:! !I6T%B:@8E6 TE6T
B$&>''/.)7
B$&>''/.)7
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PROCESS CONTROL PRACTICES, PROJECT 1
;c > /.7'
;c > /.7'
Result B: FIC31 OPEN LOOP TEST
!ata, =+ > 0, Ѳ > 52/
a>
>
b>
Response Rate,RR
Page
>
PROCESS CONTROL PRACTICES, PROJECT 1
%%>
.
>
.
6.0 mm
> 20.*) 1min
1 min
Dead Time,Td
Td$time& > Td$length& x b
'./ mm x
> /./'- min Time Constant,Tc
Tc$time& > Tc$length& x b
)./ mm x
> /./* min Table Table 3b) Tuning Rules by Cien Ci en , !rones " Res#ic$ %C!R)
B$& > '35 %%Td %%Td
I > Td
'35 $20.*)&$/./'-& > ')'./2
> /./'- min
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PROCESS CONTROL PRACTICES, PROJECT 1
; 8 >
> /./0)3 > /.0*
CLOSED LOOP TEST
SET PO&NT TEST %SP)
LO'D D&ST(R'NCES TEST
B$&>')'./2
B$&>')'./2
;c > /.0*
;c > /.0*
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PROCESS CONTROL PRACTICES, PROJECT 1
Result C: FIC31 OPEN LOOP TEST
!ata, =+ > '), Ѳ > 0//
a>
>
b>
>
Response Rate,RR
%%>
.
>
.
6.0 mm 1 min
Dead Time,Td
Td$time& > Td$length& x b
'./ mm x
> /./'- min Time Constant,Tc Page 10
> -).*0 1min
PROCESS CONTROL PRACTICES, PROJECT 1 Tc$time& > Tc$length& x b
)./ mm x
> /./* min Table Table 3b) Tuning Rules by Cien Ci en , !rones " Res#ic$ %C!R)
B$& > '35 %%Td %%Td
I > Td
'35 $-).*0&$/./'-& > '*'.)'
; 8 >
> /./'- min
> /./53
CLOSED LOOP TEST
SET PO&NT TEST %SP)
LO'D D&ST(R'NCES TEST
B$&>'*'.)'
B$&>'*'.)'
;c > /.53
;c > /.53
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PROCESS CONTROL PRACTICES, PROJECT 1
Overall Result Open Loop Test Test S et
∆MV ,%
RR,mn !1
T" ,mn
T#,mn
$B %
I,mn
#
A
4
33.02
0.02
0.045
110.29
0.02
0.91
B
8
48.32
0.015
0.03
121.04
0.015
0.83
C
12
52.38
0.015
0.03
131.21
0.015
0.76
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PROCESS CONTROL PRACTICES, PROJECT 1
Overall Result Close" Loop Test Set
A
$&RFORMA'C& T&ST (STAT)S*
PB % 110.29
I,min 0.02
K% 0.91
SP TEST
LOAD DISTURBANE TEST
O!"#$m&"$ 'i() *m++
Un$"#$m&"$ 'i() *m++ *-i++(in
*-i++(in ')"n in
')"n in -n(in//*+
-n(in//*+
B C
121.04 0.02 131.21 0.02
0.83 0.76
O!"#$m&"$
Un$"#$m&"$ 'i() *m++ *-i++(in
O!"#$m&"$
')"n in -n(in//*+ Un$"#$m&"$ 'i() *m++ *-i++(in ')"n in -n(in//*+
4.0 DISCUSSION
This project was title Ccontrollability of flow control using various tuning ruleD.The flow was control by using #I8 *' e"uipment. The aim of the study to compare the value of flow control calculation by using different value of + $manipulated variable& such as 2, 0, and '). :n open loop test has been performed to the temperature control loop by making the + changes for all three processes at 2 , 0 and ') . The purpose of the open loop test is to obtain the
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PROCESS CONTROL PRACTICES, PROJECT 1 response rate %% and dead time Td. These both value is used to calculate the optimum I! value that has been used in the closed loop test. 6et point change test or closed loop test was conducted in order to study the effect of different response rate obtained from open loop test. These test was used the table *b&Tuning %ules by 8hien, Frones and %eswick $8F%&. #irstly from the experiment #I8 *',we have done an open loop test which we set the value of + at *- .Then we increase the value of + by 2 from the initial initial values and then we decreased back the value to original value after a few seconds. Then from the graph obtained, we calculate the response rate $%%& , dead time $Td& and time constant $Tc& by using the tangent method. #rom the calculation by using tangent method , the %% value was **./) min<', Td was /./) min and for the time constant , Tc the the value value was was /./2/./2- min.T min.The hen n by usin using g tabl tablee *b&Tu *b&Tuni ning ng %ule %uless by 8hie 8hien, n, Fron Frones es and and %esw %eswic ick k $8F%& ,we calculate the optimum proportional band, B by using I! mode, the value was ''/.)7. Then for the gain , ;c we get /.7' while for the integral time, I was /./) min. There are no value for derivative time,!. #or the second time, the step from open loop test was repeat but we increase the value of + by 0 from the initial values and we decreased back the value to original value after a few seconds. Then from the we calculate calculate the response response rate $%%& , dead time $Td& and time constant constant $Tc& by using the tangent method. #rom the calculation by using tangent method , the %% value was 20.*) min<', Td was /./'- min and for the time constant , Tc the value was /./* min. Then Then by using using table table *b&Tu *b&Tunin ning g %ules %ules by 8hien, 8hien, Frones Frones and %eswic %eswick k $8F%& $8F%& ,we calcul calculate ate the optimum proportional band, B by using I! mode, the value was ''/.)7. Then for the gain , ;c we get /.0* while for the integral time, I was /./'- min. There There are no value for derivative time,!. #or the third time, the step from open loop test was repeat but we increase the value of + by ') from the initial values and we decreased back the value to original value after a few seconds. Then from the we calculate calculate the response response rate $%%& , dead time $Td& and time constant constant $Tc& by using the
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PROCESS CONTROL PRACTICES, PROJECT 1 tangent method. #rom the calculation by using tangent method , the %% value was -).*0 min<', Td was /./'- min and for the time constant , Tc the value was /./* min. Then Then by using using table table *b&Tu *b&Tunin ning g %ules %ules by 8hien, 8hien, Frones Frones and %eswic %eswick k $8F%& $8F%& ,we calcul calculate ate the optimum proportional band, B by using I! mode, the value was '*'.)'. Then for the gain , ;c we get /.53 while for the integral time, I was /./'- min. There are no value for derivative time,!. P)
O)&*+oo
O+-#ll(#'/
SP1 SP2 R#+& (#%&
U'&*+oo(US
S&((l#'/ (#%&T+
Close" Loop $ro#ess Response #rom comparison between all set :, B and 8. The different is in term of roportional band and I. There different between closed loops for each process response is the effect of proportional of a GI control controller ler.. #or the value value of B set :, B ,and 8 respe respecti ctivel vely y
which which is ''/.)7 ''/.)7, , ')'./2 ')'./2 and
'*'.)'.:s we can see for each proses response the graph 8 which is more overshoot compare to B and followed by the 8 .This is because, when increasing the B value will cause the proses become overshoot for a while makes the controller action $+&slower, which in turn slowing down the proses response. :fter a period of time, as we can see that process is oscillating continuously at a constant amplitude for each set : , B and 8. By comparing be tween set : ,B and 8 , the set 8 have high h igh value of B shown that the proses become slower proses response if compare to set : and set B.B value is calculated from open loop proses by determine first %esponse rate , !ead time $T d& and !ead constant Page 15
PROCESS CONTROL PRACTICES, PROJECT 1 $T8& in order to determine second value of optimum B ,and I by using table *b& tunning rule by 8hien ,Frones and %eswick$8F%&. 6econd effect from each graph set :, B and 8 is effect of integral of a GI controller. #or each set the value of I is different which is /./)min, /./'-min and /./'- min for each set :, B and 8 respectively. #rom each set different value of I due to different closed loop response rate .The set : have slowest response rate compare to set B and 8 which have faster response rate. Thus, this can conclude that, when decreasing the value of I , the proses become faster response towards the set point .#rom this experiment the set 8 and B which have faster response compared to set :. :.
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PROCESS CONTROL PRACTICES, PROJECT 1
5.0 CONCLUSION :s a conclusion, this experiment has achieve its objective which is to compare the value of flow control calculation by using different value of + $manipulated variable& such as 2, 0, and '). s. Hhen we increase the changing in + value, the value of controller gain, ;c will decrease and can affect the respond of the process to become slower and the process become more stable. The lowest and minimum value of response rate, %% produces highest value of B and the lowest value of ;c. The higher the value of B the slower the controller action, thus slow down the process response. It is not suitable to be used in industry since it wills longer the time to settle down after we make some changes to the process.
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