SlideShare a Scribd company logo
Abstract— The proposed PID tuning method has similar
approach to the recently published paper of Shamsuzzoha and
Skogestad (2010). It is one step procedure to obtain the PI/PID
setting which gives the better performance and robustness. The
method requires one closed-loop step setpoint response
experiment using a proportional only controller with gain Kc0.
On the bases of simulations for a range of first-order with delay
processes, simple correlations have been derived to give PI/PID
controller settings. The controller gain (Kc/Kc0) is only a
function of the overshoot observed in the setpoint experiment.
The controller integral and derivative time (τI and τD) is mainly
a function of the time to reach the first peak (tp). The proposed
tuning method shows better performance than Shamsuzzoha
and Skogestad [1] for broad range of processes.
I. INTRODUCTION
He proportional, integral, and derivative (PID) controller
is widely used in the process industries due to its
simplicity, robustness and wide ranges of applicability in the
regulatory control layer. One survey of Desborough and
Miller [2] indicates that more than 97% of regulatory
controllers utilize the PID algorithm. A recent survey of
Kano and Ogawa [3] shows that the ratio of applications of
different type of controller e.g., PID control, conventional
advanced control and model predictive control is about
100:10:1. Although the PID controller has only three
adjustable parameters, they are difficult to be tuned properly.
One reason is that tedious plant tests are required to obtain
improved controller setting.
There are two approaches for the controller tuning and one
may use open-loop or closed-loop plant tests. Most tuning
approaches are based on open-loop plant information;
typically the plant’s gain (k), time constant (τ) and time delay
(θ). One popular approach is direct synthesis (Seborg et
Manuscript received September 25, 2011.
Acknowledgement: The authors would like to acknowledge the support
(Project Number: SB101016) provided by the Deanship of Scientific
Research at King Fahd University of Petroleum and Minerals (KFUPM).
M. Shamsuzzoha is with the Department of Chemical Engineering, King
Fahd University of Petroleum and Minerals, Daharan, 31261, Kingdom of
Saudi Arabia, Phone: +966-3-860-7360, (email: mshams@kfupm.edu.sa)
Moonyong Lee is with the School of Chemical Engineering and
Technology, Yeungnam University, Kyongsan 712-749, Korea, Phone:
+82-53-810-2512, (email: mynlee@ynu.ac.kr)
Hiroya Seki is with the Chemical Resources Laboratory, Tokyo Institute
of Technology, 4259-R1-19 Nagatsuta, Midori-ku, Yokohama, 226-8503
Japan (e-mail: hseki@pse.res.titech.ac.jp)
al.,[4]) and other is the IMC-PID tuning method of Rivera et
al.[5]. Both the methods give very good performance for
setpoint changes but sluggish responses to input (load)
disturbances for lag-dominant (including integrating)
processes with τ/θ>10. To improve load disturbance
rejection, Skogestad [6] proposed the modified SIMC
method where the integral time is reduced for processes with
a large value of the time constant τ. The SIMC rule has one
tuning parameter, the closed-loop time constant τc, and for
“fast and robust” control is recommended to choose τc= θ,
where θ is the (effective) time delay. However, these
approaches require that one first obtains an open-loop model
of the process and then tuning of the control loop. There are
two problems here. First, an open-loop experiment, for
example a step test, is normally needed to get the required
process data. This may be time consuming and may upset the
process and even lead to process runaway. Second,
approximations are involved in obtaining the process
parameters (e.g., k, τ and θ) from the data.
The main alternative is to use closed-loop experiments. One
approach is the classical method of Ziegler-Nichols [7]
which requires very little information about the process.
However, there are several disadvantages. First, the system
needs to be brought its limit of instability and a number of
trials may be needed to bring the system to this point.
Another disadvantage is that the Ziegler-Nichols [7] tunings
do not work well on all processes. It is well known that the
recommended settings are quite aggressive for lag-dominant
(integrating) processes (Tyreus and Luyben,[8]) and quite
slow for delay-dominant process (Skogestad, [6]). A third
disadvantage of the Ziegler-Nichols [7]) method is that it can
only be used on processes for which the phase lag exceeds -
180 degrees at high frequencies. For example, it does not
work on a simple second-order process. Recently,
Shamsuzzoha and Skogestad [1] have developed new
procedure for PI/PID tuning method in closed-loop mode.
Their method is based on the SIMC tuning rule and provides
satisfactory result for both the performance and robustness.
For the PID tuning parameter they need to repeat the
experiment with PD controller on the basis of the prior
information obtain from P controller test. They
recommended adding the derivative action only for dominant
second-order process.
Closed-loop PI/PID Controller Tuning for Stable and Unstable
Processes
M.Shamsuzzoha*, Moonyong Lee, Hiroya Seki
T
2012 American Control Conference
Fairmont Queen Elizabeth, Montréal, Canada
June 27-June 29, 2012
978-1-4577-1096-4/12/$26.00 ©2012 AACC 2368
Therefore, it is important to have other tuning method based
on the closed-loop experiment which gives better
performance and robustness. In this method it is simple to
obtain the PID tuning parameters in one step for improved
performance while satisfying the other concern during the
closed-loop experiment like reduces the number of trails, and
works for a wide range of processes. IMC-PID Controller
Tuning Rule
The motivation of this section is to develop IMC-PID
controller tuning for first order process with delay. In
process control, a first-order process with time delay is a
common representation of the process dynamics:
-
( )
1
s
ke
g s
s
θ
τ
=
+
(1)
Here k is the process gain, τ lag time constant and θ the time
delay. Most processes in the chemical industries can be
satisfactorily controlled using a PID controller:
( )
1
1c D
I
c s K s
s
τ
τ
 
= + + 
 
(2)
The other structure of the PID controller like series form of
PID can easily be transform from Eq. (2). The conventional
feedback controller which is equivalent to the IMC controller
can be expressed by following relation.
( )
1
q
c s
gq
=
− %
(3)
where g% denotes the process transfer function, c and q are the
conventional and IMC controller, respectively. The IMC
controller is designed in two steps:
Step 1: The process model g% is decomposed into two parts:
M Ag p p=% (4)
where pm and pA are the portions of the model inverted and
not inverted, respectively, by the controller (pA is usually a
non-minimum phase and contains dead times and/or right
half plane zeros); pA(0)=1.
Step 2: The IMC controller is designed by
-1
Mq p f= (5)
The IMC filter f is usually given as 1( 1)r
cf sτ= + and cτ is an
adjustable parameter which controls the tradeoff between the
performance and robustness; r is selected to be large enough
to make the IMC controller semi-proper. Consider
approximation of the dead time term in Eq. (1) by first order
Pade approximation:
( )
1-
2
( )
1 1
2
k s
g s
s s
θ
θ
τ
 
 
 =
 
+ + 
 
(6)
The resulting IMC-PID tuning formula after simplification is
obtain in Eq.(7) for the given process in Eq. (1).
( )
2
2
c
c
K
k
τ θ
τ θ
+
=
+
(7a)
2
I c
θ
τ τ= + (7b)
2
D
τθ
τ
τ θ
=
+
(7c)
The PID controller designed on the basis of the IMC
principle provides excellent set-point tracking, but has a
sluggish disturbance response, especially for processes with
a small θ/τ ratio [4,6,9]. To improve the load disturbance
response Skogestad [6] recommended modifying the integral
time as
I cτ =4(τ +θ) (8)
Therefore, the integral time in Eq.(7b) is modified for the
improved disturbance
I cτ =min , 4(τ +θ)
2
c
θ
τ
  
+  
  
(9)
τc= θ has been recommend which gives maximum sensitivity
(Ms)=1.70 approximately. The revised tuning method for the
PID controller tuning is given as:
2
3
cK
k
τ θ
θ
+
= (10a)
min , 8
2
I
θ
τ τ θ
  
= +  
  
(10b)
2
D
τθ
τ
τ θ
=
+
(10c)
I. CLOSED-LOOP EXPERIMENT
This section is devoted for the development of the PI/PID
controller based on the closed-loop data which resembles the
proposed tuning method in Eq.(10). The simplest closed-
loop experiment is probably a setpoint step response (Fig. 1)
where one maintains full control of the process, including the
change in the output variable. The simplest to observe is the
time tp to reach the (first) overshoot and its magnitude, and
this information is therefore the basis for the proposed
method.
The proposed procedure is as follows (Shamsuzzoha and
Skogestad, [1]):
1. Switch the controller to P-only mode (for example,
increase the integral time τI to its maximum value or set the
integral gain KI to zero). In an industrial system, with
bumpless transfer, the switch should not upset the process.
2. Make a setpoint change that gives an overshoot between
0.10 (10%) and 0.60 (60%); about 0.30 (30%) is a good
value. Record the controller gain Kc0 used in the experiment.
Most likely, unless the original controller was quite tightly
tuned, one will need to increase the controller gain to get a
sufficiently large overshoot.
Note that small overshoots (less than 0.10) are not
considered because it is difficult in practice to obtain from
experimental data accurate values of the overshoot and peak
time if the overshoot is too small. Also, large overshoots
(larger than about 0.6) give a long settling time and require
2369
more excessive input changes. For these reasons we
recommend using an “intermediate” overshoot of about 0.3
(30%) for the closed-loop setpoint experiment.
3. From the closed-loop setpoint response experiment, obtain
the following values (see Fig. 1):
• Fractional overshoot, (∆yp - ∆y∞) /∆y∞
• Time from setpoint change to reach peak output
(overshoot), tp
• Relative steady state output change, b = ∆y∞/∆ys.
Here the output variable changes are:
∆ys: Setpoint change
∆yp: Peak output change (at time tp)
∆y∞: Steady-state output change after setpoint step test
To find ∆y∞ one needs to wait for the response to settle,
which may take some time if the overshoot is relatively large
(typically, 0.3 or larger). In such cases, one may stop the
experiment when the setpoint response reaches its first
minimum and record the corresponding output, ∆yu.
∆y∞ = 0.45(∆yp + ∆yu) (11)
The details about how to obtaining Eq.(11) is given in
Shamsuzzoha and Skogestad (2010).
II. CORRELATION BETWEEN SETPOINT RESPONSE AND THE
IMC-PID-SETTINGS
The objective of this paper is to provide a one step
procedure in closed-loop for controller tuning similar to the
Shamsuzzoha and Skogestad (2010) and Ziegler-Nichols
(1942) method. Thus, the goal is to derive a correlation,
preferably as simple as possible, between the setpoint
response data (Fig. 1) and the Proposed PID settings in Eq.
(10), initially with the choice τc=θ. For this purpose, we
considered 15 first-order with delay models g(s)=ke-θs
/(τs+1)
that cover a wide range of processes; from delay-dominant to
lag-dominant (integrating):
τ/θ=0.1,0.2,0.4,0.8,1.0,1.5,2.0,2.5,3.0,7.5,10.0,20.0,50.0,100
Since we can always scale time with respect to the time delay
(θ) and since the closed-loop response depends on the
product of the process and controller gains (kKc) we have
without loss of generality used in all simulations k=1 and
θ=1.
For each of the 15 process models (values of τ/θ), we
obtained the PID-settings using Eq. (10) with the choice
τc=θ. Furthermore, for each of the 15 processes we generated
6 closed-loop step setpoint responses using P-controllers that
give different fractional overshoots.
Overshoot= 0.10, 0.20, 0.30, 0.40, 0.50 and 0.60
In total, we then have 90 setpoint responses, and for each of
these we record four data: the P-controller gain Kc0 used in
the experiment, the fractional overshoot, the time to reach
the overshoot (tp), and the relative steady-state change, b =
∆y∞/∆ys.
Controller gain (Kc). We first seek a relationship between
the above four data and the corresponding proposed
controller gain Kc. Indeed, as illustrated in Fig. 2, where we
plot kKc as a function of kKc0 for the 90 setpoint
experiments, the ratio Kc/Kc0 is approximately constant for a
fixed value of the overshoot, independent of the value of τ/θ.
Thus, we can write
c
c0
K
=A
K
(12)
py∆
pt
y∞∆ sy∆
t
0t =
θ
uy∆
sy∆
Fig. 1. Closed-loop step setpoint response with P-only control.
0 20 40 60 80 100 120
0
10
20
30
40
50
60
70
kKc0
kKc
0.10 overshoot
kK
c
=1.1621kK
c0
0.20 overshoot
kK
c
=0.9701kK
c0
0.30 overshoot
kK
c
=0.841kK
c0
0.40 overshoot
kK
c
=0.7453kK
c0
0.50 overshoot
kK
c
=0.6701kK
c0
0.60 overshoot
kK
c
=0.6083kK
c0
Fig. 2. Relationship between P-controller gain kKc0 used in setpoint
experiment and corresponding proposed controller gain (Eq. 10a) kKc.
where the ratio A is a function of the overshoot only. In Fig.
3 we plot the value of A, which is obtained as the best fit of
the slopes of the lines in Fig. 2, as a function of the
overshoot. The following equation (solid line in Fig. 3) fits
the data in Fig. 2 well and given as:
A=[1.55(overshoot)2
-2.159 (overshoot)+1.35] (13)
2370
0.1 0.2 0.3 0.4 0.5 0.6
0.7
0.8
0.9
1
1.1
overshoot (fractional)
A
y = 1.55*(overshoot)2
- 2.159*(overshoot) + 1.35
Fig. 3. Variation of A with overshoot using data (slopes) from Fig. 2.
0.1 0.3 0.5 0.6
0
0.1
0.2
0.3
0.4
0.5
Overshoot
θ/tp
0.43 (τI1
)
0.305 (τI2
)
τ/θ=0.1
τ/θ=8
τ/θ=100
τ/θ=1
Fig. 4. Ratio between delay and setpoint overshoot peak time (θ/tp) for P-
only control of first-order with delay processes (solid lines); Dotted lines:
values used in final correlations, Shamsuzzoha and Skogestad (2010).
Integral time (τI). It is interesting to find a simple
correlation for the integral time. The proposed method in Eq.
(10b) uses the minimum of two values, it seems reasonable
to look for a similar relationship, that is, to find one value
(τI1 =τ) for processes with a relatively large delay, and
another value (τI2 =8θ) for processes with a relatively small
delay including integrating processes.
(1) Process with relatively large delay: This case arise
when processes have a relatively large delay i.e., τ/θ<8, the
integral action in the proposed tuning rule is to use τI = (τ+
θ/2). Rearrangement of Eq.(10a) is given as
3
2
ckK θ θ
τ
−
= (14)
Adding both the side θ/2 in Eq.(14) and substitute (τ+
θ/2)=τI, we get
I 1.5 ckKτ θ= (15)
In Eq. (15), we also need the value of the process gain k, and
to this effect write
kKc= kKc0.Kc/ Kc0 (16)
Here, the value of the loop gain kKc0 for the P-control
setpoint experiment is given from the value of b:
c0
b
kK =
(1-b)
(17)
Substituting kKc from Eq. (17) and Kc/ Kc0=A into Eq. (15)
and given as
I
b
1.5A
(1-b)
τ θ= (18)
To prove this, the closed-loop setpoint response is ∆y/∆ys =
gc/(1+gc) and with a P-controller with gain Kc0, the steady-
state value is ∆y∞/∆ys = kKc0/(1+kKc0)=b and we derive
Eq.(17). The absolute value is included to avoid problems if
b>1, as may occur for an unstable process or because of
inaccurate data.
It is possible to obtain the value of time delay θ directly from
the closed-loop setpoint response, but usually this is not
always easy task. The reasonable correlation has been
developed by Shamsuzzoha and Skogestad [1] for the θ and
the setpoint peak time tp which is easier to observe.
For processes with a relatively large time delay (τ/θ<8), the
ratio θ/tp varies between 0.27 (for τ/θ= 8 with overshoot=0.1)
and 0.5 (for τ/θ=0.1 with all overshoots). For the
intermediate overshoot of 0.3, the ratio θ/tp varies between
0.32 and 0.50. A conservative choice would be to use
θ=0.5tp because a large value increases the integral time.
However, to improve performance for processes with smaller
time delays, we propose to use θ=0.43tp which is only 14%
lower than 0.50 (the worst case).
In summary, we have for process with a relatively large time
delay:
0.645
(1- )
I p
b
A t
b
τ = (19)
(2) Process with relatively small delay. Shamsuzzoha and
Skogestad [1] method and in this proposed tuning rule have
same integral action for the lag-dominant process. The
integral time for a lag-dominant (including integrating)
process with τ/θ>8 the proposed tuning rule for integral time
gives
τI2=8θ (20)
For τ/θ>8 we see from Fig. (4) that the ratio θ/tp varies
between 0.25 (for τ/θ=100 with overshoot=0.1) and 0.36 (for
τ/θ=8 with overshoot 0.6). We select to use the average value
θ= 0.305tp which is only 15% lower than 0.36 (the worst
case). Also note that for the intermediate overshoot of 0.3,
the ratio θ/tp varies between 0.30 and 0.32. In summary, we
have for a lag-dominant process
I2 pτ =2.44t (21)
Conclusion. Therefore, the integral time τI is obtained as the
minimum of the above two values:
I pτ =min 0.645 , 2.44t
(1- )
p
b
A t
b
 
  
 
(22)
2371
Derivative action (τD): Although a significant number of the
PID controllers switched off their derivative part but proper
use of derivative action can increase stability and improve
the closed-loop performance. The derivative action is very
important for slow moving loops where overshoot is
undesirable e.g., temperature loop. The motivation of this
section is to develop the approach for inclusion of the
derivative action from closed-loop data. In the proposed
study the derivative action is recommended for the process
having 1τ θ ≥ which can give performance improvement.
Substitute the value of 0.5Iτ τ θ= − into 1τ θ ≥ and after
rearrangement the resulting equation is
( )0.5
1Iτ θ
θ
−
≥ (23)
After simplification it is 1.5Iτ θ ≥ and resulting constrain is
1.0ckK ≥ . The corresponding closed-loop condition for the
derivative action is given as:
( )
b
A 1
1-b
≥ (24)
Case I: For approximately integrating process (τ>> θ),
where integral time is τI =8θ and in the closed-loop the time
delay θ= 0.305tp. The derivative time τD1 in Eq. (10c) can be
approximated as
1
0.305
0.15
2 2 2
p
D p
t
t
τθ θ
τ
τ
≈ = = = (25)
Case II: The processes with a relatively large delay, for this
case integral time τI=(τ+0.5θ) and time delay in closed-loop
is θ=0.43tp. For such cases the derivative action is
recommended only if τ/θ ≥ θ. Assuming the case when τ=θ
the τD2 is given from Eq. (10c) as
2 2
2
0.43
0.1433
2 3 3 3
p
D p
t
t
θ θ θ
τ
θ θ θ
≈ = = = =
+
(26)
The derivative action is only recommended for the process
having 1τ θ ≥ and in the closed-loop this criteria is
( )
b
A 1
1-b
≥
.
Summary: The derivative action for both the cases i.e., τD1
and τD2 are approximately same and the conservative choice
for the selection of τD is given as
( )
0.14 1
1-
D p
b
t if A
b
τ = ≥
(27)
Selection of Proportional Controller Gain (Kc0): An
overshoot of around 0.3 is recommended for the proposed
study. Sometimes achieving the P-controller gain (Kc0) via
trial and error which gives the overshoot around 0.3 can be
time consuming.
Therefore, an effective approach to get the value of Kc0
which gives the overshoot around 0.3 is very significant for
the proposed method. It is important to note that this
procedure requires initial information of the first closed-loop
experiment. Let’s assume for the first closed-loop test P-
controller gain of Kc01 is applied and resulting overshoot OS1
is achieved that is between 0.1 to 0.60 but not around 0.30.
Let the target overshoot be OS and the target P-controller
gain be Kc0. In the proposed closed-loop tuning method the
goal is to match the performance with IMC-PID tuning rule
and for this only maintains a constant P gain Kc, regardless
of the overshoot that resulted from the closed-loop setpoint
test. Ideally, Kc should be the same as that determined with
different overshoots from various closed-loop setpoint test
and the resulting correlation is given as:
( ) ( ) ( ) ( )2 2
1 1 01 01.55 OS 2.159 OS 1.35 1.55 OS 2.159 OS 1.35c cK K   − + = − +      
(28)
The above Eq.(28) gives a general guideline for choosing the
P-controller gain for the next closed-loop setpoint test. As it
is mentioned earlier the proposed method is good agreement
with the IMC-PID for the overshoot around 0.3. Therefore
the overshoot in Eq.(28) is set as 0.3 and after simplification
the gain for the next closed-loop test is recommended as:
( ) ( )( )2
0 1 1 011.19 1.45 OS 2.02 OS 1.27c cK K= − + (29)
It is important to note that we are not keen to achieve the
precise fractional overshoot of 0.3, so few trial is sufficient
to achieve the desire overshoot around 0.3 from above
equation.
III. SIMULATION
The proposed closed-loop tuning method has been tested on
broad class of the process model. It provides the acceptable
controller setting for all cases with respect to both the
performance and robustness. To show the effectiveness of
the proposed method two cases have been shown as a
representative example i.e., integrating with time delay and
higher order process with time delay. The simulation has
been conducted for three different overshoot (around 0.1, 0.3
and 0.6) and are compared with the recently reported method
of Shamsuzzoha and Skogestad[1].
Example 1: ( )
( )( )
2
1
6 1 2 1
s
s e
s s
−
− +
+ +
Example 2:
s
e
s
−
Figure 5 and 6 presents a comparison of the proposed
method with Shamsuzzoha and Skogestad [1] by introducing
a unit step change in the set-point at t = 0 and an unit step
change of load disturbance (at t = 100 for Example 1 and t =
50 for Example 2) at plant input. It is clear from Figure 5
and 6 that the proposed method gives better closed-loop
response for both the high order and integrating processes.
There are significant performance improvements in both the
case for the disturbance rejection while maintaining setpoint
performance.
The overshoot around 0.1 typically gives slower and more
robust PID-settings, whereas a large overshoot around 0.6
2372
gives more aggressive PID-settings. It is good because a
more careful step response results in more careful tunings
settings.
0 50 100 150 200
0.2
0.6
1
1.4
time
OUTPUTy
Shamsuzzoha and Skogestad method with F=1(overshoot=0.119)
Shamsuzzoha and Skogestad method with F=1 (overshoot=0.344)
Shamsuzzoha and Skogestad method with F=1(overshoot=0.608)
Proposed method with F=1 (overshoot=0.119)
Proposed method with F=1 (overshoot=0.344)
Proposed method with F=1 (overshoot=0.608)
Fig. 5. Responses for PID-control of high order process ( )
( )( )2
1
6 1 2 1
s
s e
s s
−
− +
+ +
,
Setpoint change at t=0; load disturbance of magnitude 1 at t=100.
IV. CONCLUSION
A simple approach has been developed for PI/PID controller
tuning by the closed-loop setpoint step using a P-controller
with gain Kc0. The PID-controller settings are then obtained
directly from following three data from the setpoint
experiment:
• Overshoot, (∆yp - ∆y∞) /∆y∞
• Time to reach overshoot (first peak), tp
• Relative steady state output change, b = ∆y∞/∆ys.
If one does not want to wait for the system to reach steady
state, one can use the estimate ∆y∞ = 0.45(∆yp + ∆yu).
The proposed tuning PID tuning method is:
c c0K =K A
I pτ =min 0.645 , 2.44t
(1- )
p
b
A t
b
 
  
 
( )
0.14 1
1-
D p
b
t if A
b
τ = ≥
where, A=[1.55(overshoot)2
-2.159 (overshoot)+1.35]
The proposed method works well for a wide variety of the
processes typical for process control, including the standard
first-order plus delay processes as well as integrating, high-
order, inverse response, unstable and oscillating process.
0 10 20 30 40 50 60 70 80 90 100
0
0.5
1
1.5
2
2.5
3
time
OUTPUTy
Shamsuzzoha and Skogestad method with F=1 (overshoot=0.108)
Shamsuzzoha and Skogestad method with F=1 (overshoot=0.302)
Shamsuzzoha and Skogestad method with F=1 (overshoot=0.60)
Proposed method with F=1 (overshoot=0.108)
Proposed method with F=1 (overshoot=0.302)
Proposed method with F=1 (overshoot=0.60)
Fig. 6. Responses for PID-control of integrating processes
s
e s−
, Setpoint
change at t=0; load disturbance of magnitude 1 at t=50.
V. REFERENCES
[1] M. Shamsuzzoha, S. Skogestad, “The setpoint overshoot method: A
simple and fast closed-loop approach for PID tuning”, Journal of
Process Control, vol.20, pp.1220–1234,(2010).
[2] L. D. Desborough, R. M. Miller, “Increasing customer value of
industrial control performance monitoring—Honeywell’s
experience”. Chemical Process Control–VI (Tuscon, Arizona, Jan.
2001), AIChE Symposium Series No. 326. Volume 98, USA
(2002).
[3] M. Kano, M. Ogawa, “The state of art in chemical process control in
Japan: Good practice and questionnaire survey, Journal of
Process Control, (20), pp.969-982, (2010).
[4] D. E. Seborg, T. F. Edgar, D. A. Mellichamp, “Process Dynamics
and Control”, 2nd
ed., John Wiley & Sons, New York, U.S.A,
(2004).
[5] D. E. Rivera, M. Morari, S. Skogestad, “Internal model control. 4.
PID controller design”, Ind. Eng. Chem. Res., vol.25 (1) pp. 252–
265, (1986).
[6] S. Skogestad, “Simple analytic rules for model reduction and PID
controller tuning”, Journal of Process Control, vol.13, pp.291–
309, (2003).
[7] J. G. Ziegler, N. B. Nichols, “Optimum settings for automatic
controllers”, Trans. ASME, vol. 64, pp.759-768, (1942).
[8] B. D. Tyreus, W. L. Luyben, “Tuning PI controllers for
integrator/dead time processes”, Ind. Eng. Chem. Res. pp.2628–
2631, (1992).
[9]M. Shamsuzzoha, M. Lee, “IMC-PID controller design for improved
disturbance rejection” Ind. Eng. Chem. Res, vol. 46, No. 7, 2007,
pp. 2077-2091.
2373

More Related Content

What's hot

Design and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
Design and Implementation of Discrete Augmented Ziegler-Nichols PID ControllerDesign and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
Design and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
IDES Editor
 
Design of multiloop controller for multivariable system using coefficient 2
Design of multiloop controller for multivariable system using coefficient 2Design of multiloop controller for multivariable system using coefficient 2
Design of multiloop controller for multivariable system using coefficient 2IAEME Publication
 
Control Strategy of Triple Effect Evaporators based on Solar Desalination of...
Control Strategy  of Triple Effect Evaporators based on Solar Desalination of...Control Strategy  of Triple Effect Evaporators based on Solar Desalination of...
Control Strategy of Triple Effect Evaporators based on Solar Desalination of...
IRJET Journal
 
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC SystemIRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
IRJET Journal
 
Identification-of-aircraft-gas-turbine-engines-temperature-condition-
 Identification-of-aircraft-gas-turbine-engines-temperature-condition- Identification-of-aircraft-gas-turbine-engines-temperature-condition-
Identification-of-aircraft-gas-turbine-engines-temperature-condition-Cemal Ardil
 
Design of PI controllers for achieving time and frequency domain specificatio...
Design of PI controllers for achieving time and frequency domain specificatio...Design of PI controllers for achieving time and frequency domain specificatio...
Design of PI controllers for achieving time and frequency domain specificatio...
ISA Interchange
 
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
ijscmcjournal
 
Variational quantum gate optimization on superconducting qubit system
Variational quantum gate optimization on superconducting qubit systemVariational quantum gate optimization on superconducting qubit system
Variational quantum gate optimization on superconducting qubit system
HeyaKentaro
 
Servo Fundamentals
Servo FundamentalsServo Fundamentals
Servo Fundamentalspurnima saha
 
Identification of-aircraft-gas-turbine-engine-s-temperature-condition
Identification of-aircraft-gas-turbine-engine-s-temperature-conditionIdentification of-aircraft-gas-turbine-engine-s-temperature-condition
Identification of-aircraft-gas-turbine-engine-s-temperature-conditionCemal Ardil
 
PID gain scheduling using fuzzy logic
PID gain scheduling using fuzzy logicPID gain scheduling using fuzzy logic
PID gain scheduling using fuzzy logicISA Interchange
 
Control tutorials for matlab and simulink introduction pid controller desig...
Control tutorials for matlab and simulink   introduction pid controller desig...Control tutorials for matlab and simulink   introduction pid controller desig...
Control tutorials for matlab and simulink introduction pid controller desig...
ssuser27c61e
 
PID Control
PID ControlPID Control
PID Control
khalil fathi
 
Automated Tuning and Controller Design for DC-DC Boost Converter
Automated Tuning and Controller Design  for DC-DC Boost ConverterAutomated Tuning and Controller Design  for DC-DC Boost Converter
Automated Tuning and Controller Design for DC-DC Boost Converter
IRJET Journal
 
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
IRJET Journal
 
Time response of discrete systems 4th lecture
Time response of discrete systems 4th lectureTime response of discrete systems 4th lecture
Time response of discrete systems 4th lecture
khalaf Gaeid
 
Jw3417821791
Jw3417821791Jw3417821791
Jw3417821791
IJERA Editor
 

What's hot (19)

Design and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
Design and Implementation of Discrete Augmented Ziegler-Nichols PID ControllerDesign and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
Design and Implementation of Discrete Augmented Ziegler-Nichols PID Controller
 
Design of multiloop controller for multivariable system using coefficient 2
Design of multiloop controller for multivariable system using coefficient 2Design of multiloop controller for multivariable system using coefficient 2
Design of multiloop controller for multivariable system using coefficient 2
 
Control Strategy of Triple Effect Evaporators based on Solar Desalination of...
Control Strategy  of Triple Effect Evaporators based on Solar Desalination of...Control Strategy  of Triple Effect Evaporators based on Solar Desalination of...
Control Strategy of Triple Effect Evaporators based on Solar Desalination of...
 
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC SystemIRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
IRJET- PSO Tuned PID Controller for Single-Area Multi- Source LFC System
 
Identification-of-aircraft-gas-turbine-engines-temperature-condition-
 Identification-of-aircraft-gas-turbine-engines-temperature-condition- Identification-of-aircraft-gas-turbine-engines-temperature-condition-
Identification-of-aircraft-gas-turbine-engines-temperature-condition-
 
Design of PI controllers for achieving time and frequency domain specificatio...
Design of PI controllers for achieving time and frequency domain specificatio...Design of PI controllers for achieving time and frequency domain specificatio...
Design of PI controllers for achieving time and frequency domain specificatio...
 
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
OPTIMAL PID CONTROLLER DESIGN FOR SPEED CONTROL OF A SEPARATELY EXCITED DC MO...
 
Variational quantum gate optimization on superconducting qubit system
Variational quantum gate optimization on superconducting qubit systemVariational quantum gate optimization on superconducting qubit system
Variational quantum gate optimization on superconducting qubit system
 
Servo Fundamentals
Servo FundamentalsServo Fundamentals
Servo Fundamentals
 
Identification of-aircraft-gas-turbine-engine-s-temperature-condition
Identification of-aircraft-gas-turbine-engine-s-temperature-conditionIdentification of-aircraft-gas-turbine-engine-s-temperature-condition
Identification of-aircraft-gas-turbine-engine-s-temperature-condition
 
PID gain scheduling using fuzzy logic
PID gain scheduling using fuzzy logicPID gain scheduling using fuzzy logic
PID gain scheduling using fuzzy logic
 
Control tutorials for matlab and simulink introduction pid controller desig...
Control tutorials for matlab and simulink   introduction pid controller desig...Control tutorials for matlab and simulink   introduction pid controller desig...
Control tutorials for matlab and simulink introduction pid controller desig...
 
Final Long Form Report
Final Long Form ReportFinal Long Form Report
Final Long Form Report
 
PID Control
PID ControlPID Control
PID Control
 
Automated Tuning and Controller Design for DC-DC Boost Converter
Automated Tuning and Controller Design  for DC-DC Boost ConverterAutomated Tuning and Controller Design  for DC-DC Boost Converter
Automated Tuning and Controller Design for DC-DC Boost Converter
 
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
Hybrid of Ant Colony Optimization and Gravitational Emulation Based Load Bala...
 
IJCSMC Paper
IJCSMC PaperIJCSMC Paper
IJCSMC Paper
 
Time response of discrete systems 4th lecture
Time response of discrete systems 4th lectureTime response of discrete systems 4th lecture
Time response of discrete systems 4th lecture
 
Jw3417821791
Jw3417821791Jw3417821791
Jw3417821791
 

Viewers also liked

0520 th m10.4
0520 th m10.40520 th m10.4
0520 th m10.4
Aleksandar Micic
 
Skd 141311049 muflih adinata n_stand alone controller
Skd 141311049 muflih adinata n_stand alone controllerSkd 141311049 muflih adinata n_stand alone controller
Skd 141311049 muflih adinata n_stand alone controller
Muflih Negara
 
Level Control of Tank System Using PID Controller-A Review
Level Control of Tank System Using PID Controller-A ReviewLevel Control of Tank System Using PID Controller-A Review
Level Control of Tank System Using PID Controller-A Review
IJSRD
 
Embeded system by Mitesh Kumar
Embeded system by Mitesh KumarEmbeded system by Mitesh Kumar
Embeded system by Mitesh Kumar
Mitesh Kumar
 
Pid controller by Mitesh Kumar
Pid controller by Mitesh KumarPid controller by Mitesh Kumar
Pid controller by Mitesh Kumar
Mitesh Kumar
 
PID Controller Tuning
PID Controller TuningPID Controller Tuning
PID Controller TuningAhmad Taan
 

Viewers also liked (6)

0520 th m10.4
0520 th m10.40520 th m10.4
0520 th m10.4
 
Skd 141311049 muflih adinata n_stand alone controller
Skd 141311049 muflih adinata n_stand alone controllerSkd 141311049 muflih adinata n_stand alone controller
Skd 141311049 muflih adinata n_stand alone controller
 
Level Control of Tank System Using PID Controller-A Review
Level Control of Tank System Using PID Controller-A ReviewLevel Control of Tank System Using PID Controller-A Review
Level Control of Tank System Using PID Controller-A Review
 
Embeded system by Mitesh Kumar
Embeded system by Mitesh KumarEmbeded system by Mitesh Kumar
Embeded system by Mitesh Kumar
 
Pid controller by Mitesh Kumar
Pid controller by Mitesh KumarPid controller by Mitesh Kumar
Pid controller by Mitesh Kumar
 
PID Controller Tuning
PID Controller TuningPID Controller Tuning
PID Controller Tuning
 

Similar to Acc shams

MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
Journal For Research
 
Somasundarreddy2020
Somasundarreddy2020Somasundarreddy2020
Somasundarreddy2020
parry2125
 
Optimised control using Proportional-Integral-Derivative controller tuned usi...
Optimised control using Proportional-Integral-Derivative controller tuned usi...Optimised control using Proportional-Integral-Derivative controller tuned usi...
Optimised control using Proportional-Integral-Derivative controller tuned usi...
IJECEIAES
 
Optimized proportional integral derivative (pid) controller for the exhaust t...
Optimized proportional integral derivative (pid) controller for the exhaust t...Optimized proportional integral derivative (pid) controller for the exhaust t...
Optimized proportional integral derivative (pid) controller for the exhaust t...Ali Marzoughi
 
Co36544546
Co36544546Co36544546
Co36544546
IJERA Editor
 
A New Approach for Design of Model Matching Controllers for Time Delay System...
A New Approach for Design of Model Matching Controllers for Time Delay System...A New Approach for Design of Model Matching Controllers for Time Delay System...
A New Approach for Design of Model Matching Controllers for Time Delay System...
IJERA Editor
 
PID Control of Runaway Processes - Greg McMillan Deminar
PID Control of Runaway Processes - Greg McMillan DeminarPID Control of Runaway Processes - Greg McMillan Deminar
PID Control of Runaway Processes - Greg McMillan Deminar
Jim Cahill
 
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
IRJET Journal
 
Distributed Control System Applied in Temperatur Control by Coordinating Mult...
Distributed Control System Applied in Temperatur Control by Coordinating Mult...Distributed Control System Applied in Temperatur Control by Coordinating Mult...
Distributed Control System Applied in Temperatur Control by Coordinating Mult...
TELKOMNIKA JOURNAL
 
Classical Techniques for PID Tunning: Review
Classical Techniques for PID Tunning: ReviewClassical Techniques for PID Tunning: Review
Classical Techniques for PID Tunning: Review
IRJET Journal
 
Fuzzy gain scheduling control apply to an RC Hovercraft
Fuzzy gain scheduling control apply to an RC Hovercraft  Fuzzy gain scheduling control apply to an RC Hovercraft
Fuzzy gain scheduling control apply to an RC Hovercraft
IJECEIAES
 
Modern Control - Lec 06 - PID Tuning
Modern Control - Lec 06 - PID TuningModern Control - Lec 06 - PID Tuning
Modern Control - Lec 06 - PID Tuning
Amr E. Mohamed
 
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy ControllerIRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
IRJET Journal
 
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
ijics
 
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
ijcisjournal
 
B010411016
B010411016B010411016
B010411016
IOSR Journals
 
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
ijsc
 

Similar to Acc shams (20)

PID Tuning Rules
PID Tuning RulesPID Tuning Rules
PID Tuning Rules
 
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...
 
Somasundarreddy2020
Somasundarreddy2020Somasundarreddy2020
Somasundarreddy2020
 
Optimised control using Proportional-Integral-Derivative controller tuned usi...
Optimised control using Proportional-Integral-Derivative controller tuned usi...Optimised control using Proportional-Integral-Derivative controller tuned usi...
Optimised control using Proportional-Integral-Derivative controller tuned usi...
 
Optimized proportional integral derivative (pid) controller for the exhaust t...
Optimized proportional integral derivative (pid) controller for the exhaust t...Optimized proportional integral derivative (pid) controller for the exhaust t...
Optimized proportional integral derivative (pid) controller for the exhaust t...
 
1011ijaia03
1011ijaia031011ijaia03
1011ijaia03
 
Co36544546
Co36544546Co36544546
Co36544546
 
40620130101001
4062013010100140620130101001
40620130101001
 
A New Approach for Design of Model Matching Controllers for Time Delay System...
A New Approach for Design of Model Matching Controllers for Time Delay System...A New Approach for Design of Model Matching Controllers for Time Delay System...
A New Approach for Design of Model Matching Controllers for Time Delay System...
 
PID Control of Runaway Processes - Greg McMillan Deminar
PID Control of Runaway Processes - Greg McMillan DeminarPID Control of Runaway Processes - Greg McMillan Deminar
PID Control of Runaway Processes - Greg McMillan Deminar
 
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
Computation of Simple Robust PI/PID Controller Design for Time-Delay Systems ...
 
Distributed Control System Applied in Temperatur Control by Coordinating Mult...
Distributed Control System Applied in Temperatur Control by Coordinating Mult...Distributed Control System Applied in Temperatur Control by Coordinating Mult...
Distributed Control System Applied in Temperatur Control by Coordinating Mult...
 
Classical Techniques for PID Tunning: Review
Classical Techniques for PID Tunning: ReviewClassical Techniques for PID Tunning: Review
Classical Techniques for PID Tunning: Review
 
Fuzzy gain scheduling control apply to an RC Hovercraft
Fuzzy gain scheduling control apply to an RC Hovercraft  Fuzzy gain scheduling control apply to an RC Hovercraft
Fuzzy gain scheduling control apply to an RC Hovercraft
 
Modern Control - Lec 06 - PID Tuning
Modern Control - Lec 06 - PID TuningModern Control - Lec 06 - PID Tuning
Modern Control - Lec 06 - PID Tuning
 
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy ControllerIRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
IRJET- Speed Control of Induction Motor using Hybrid PID Fuzzy Controller
 
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
 
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
DESIGN OF PID CONTROLLERS INTEGRATOR SYSTEM WITH TIME DELAY AND DOUBLE INTEGR...
 
B010411016
B010411016B010411016
B010411016
 
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
Performance Based Comparison Between Various Z-N Tuninng PID And Fuzzy Logic ...
 

Recently uploaded

The Benefits and Techniques of Trenchless Pipe Repair.pdf
The Benefits and Techniques of Trenchless Pipe Repair.pdfThe Benefits and Techniques of Trenchless Pipe Repair.pdf
The Benefits and Techniques of Trenchless Pipe Repair.pdf
Pipe Restoration Solutions
 
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdfAKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
SamSarthak3
 
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
obonagu
 
Architectural Portfolio Sean Lockwood
Architectural Portfolio Sean LockwoodArchitectural Portfolio Sean Lockwood
Architectural Portfolio Sean Lockwood
seandesed
 
AP LAB PPT.pdf ap lab ppt no title specific
AP LAB PPT.pdf ap lab ppt no title specificAP LAB PPT.pdf ap lab ppt no title specific
AP LAB PPT.pdf ap lab ppt no title specific
BrazilAccount1
 
Fundamentals of Electric Drives and its applications.pptx
Fundamentals of Electric Drives and its applications.pptxFundamentals of Electric Drives and its applications.pptx
Fundamentals of Electric Drives and its applications.pptx
manasideore6
 
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
bakpo1
 
power quality voltage fluctuation UNIT - I.pptx
power quality voltage fluctuation UNIT - I.pptxpower quality voltage fluctuation UNIT - I.pptx
power quality voltage fluctuation UNIT - I.pptx
ViniHema
 
Runway Orientation Based on the Wind Rose Diagram.pptx
Runway Orientation Based on the Wind Rose Diagram.pptxRunway Orientation Based on the Wind Rose Diagram.pptx
Runway Orientation Based on the Wind Rose Diagram.pptx
SupreethSP4
 
Nuclear Power Economics and Structuring 2024
Nuclear Power Economics and Structuring 2024Nuclear Power Economics and Structuring 2024
Nuclear Power Economics and Structuring 2024
Massimo Talia
 
DESIGN A COTTON SEED SEPARATION MACHINE.docx
DESIGN A COTTON SEED SEPARATION MACHINE.docxDESIGN A COTTON SEED SEPARATION MACHINE.docx
DESIGN A COTTON SEED SEPARATION MACHINE.docx
FluxPrime1
 
weather web application report.pdf
weather web application report.pdfweather web application report.pdf
weather web application report.pdf
Pratik Pawar
 
J.Yang, ICLR 2024, MLILAB, KAIST AI.pdf
J.Yang,  ICLR 2024, MLILAB, KAIST AI.pdfJ.Yang,  ICLR 2024, MLILAB, KAIST AI.pdf
J.Yang, ICLR 2024, MLILAB, KAIST AI.pdf
MLILAB
 
Student information management system project report ii.pdf
Student information management system project report ii.pdfStudent information management system project report ii.pdf
Student information management system project report ii.pdf
Kamal Acharya
 
Water Industry Process Automation and Control Monthly - May 2024.pdf
Water Industry Process Automation and Control Monthly - May 2024.pdfWater Industry Process Automation and Control Monthly - May 2024.pdf
Water Industry Process Automation and Control Monthly - May 2024.pdf
Water Industry Process Automation & Control
 
Planning Of Procurement o different goods and services
Planning Of Procurement o different goods and servicesPlanning Of Procurement o different goods and services
Planning Of Procurement o different goods and services
JoytuBarua2
 
WATER CRISIS and its solutions-pptx 1234
WATER CRISIS and its solutions-pptx 1234WATER CRISIS and its solutions-pptx 1234
WATER CRISIS and its solutions-pptx 1234
AafreenAbuthahir2
 
MCQ Soil mechanics questions (Soil shear strength).pdf
MCQ Soil mechanics questions (Soil shear strength).pdfMCQ Soil mechanics questions (Soil shear strength).pdf
MCQ Soil mechanics questions (Soil shear strength).pdf
Osamah Alsalih
 
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
thanhdowork
 
Gen AI Study Jams _ For the GDSC Leads in India.pdf
Gen AI Study Jams _ For the GDSC Leads in India.pdfGen AI Study Jams _ For the GDSC Leads in India.pdf
Gen AI Study Jams _ For the GDSC Leads in India.pdf
gdsczhcet
 

Recently uploaded (20)

The Benefits and Techniques of Trenchless Pipe Repair.pdf
The Benefits and Techniques of Trenchless Pipe Repair.pdfThe Benefits and Techniques of Trenchless Pipe Repair.pdf
The Benefits and Techniques of Trenchless Pipe Repair.pdf
 
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdfAKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
AKS UNIVERSITY Satna Final Year Project By OM Hardaha.pdf
 
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
在线办理(ANU毕业证书)澳洲国立大学毕业证录取通知书一模一样
 
Architectural Portfolio Sean Lockwood
Architectural Portfolio Sean LockwoodArchitectural Portfolio Sean Lockwood
Architectural Portfolio Sean Lockwood
 
AP LAB PPT.pdf ap lab ppt no title specific
AP LAB PPT.pdf ap lab ppt no title specificAP LAB PPT.pdf ap lab ppt no title specific
AP LAB PPT.pdf ap lab ppt no title specific
 
Fundamentals of Electric Drives and its applications.pptx
Fundamentals of Electric Drives and its applications.pptxFundamentals of Electric Drives and its applications.pptx
Fundamentals of Electric Drives and its applications.pptx
 
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
一比一原版(SFU毕业证)西蒙菲莎大学毕业证成绩单如何办理
 
power quality voltage fluctuation UNIT - I.pptx
power quality voltage fluctuation UNIT - I.pptxpower quality voltage fluctuation UNIT - I.pptx
power quality voltage fluctuation UNIT - I.pptx
 
Runway Orientation Based on the Wind Rose Diagram.pptx
Runway Orientation Based on the Wind Rose Diagram.pptxRunway Orientation Based on the Wind Rose Diagram.pptx
Runway Orientation Based on the Wind Rose Diagram.pptx
 
Nuclear Power Economics and Structuring 2024
Nuclear Power Economics and Structuring 2024Nuclear Power Economics and Structuring 2024
Nuclear Power Economics and Structuring 2024
 
DESIGN A COTTON SEED SEPARATION MACHINE.docx
DESIGN A COTTON SEED SEPARATION MACHINE.docxDESIGN A COTTON SEED SEPARATION MACHINE.docx
DESIGN A COTTON SEED SEPARATION MACHINE.docx
 
weather web application report.pdf
weather web application report.pdfweather web application report.pdf
weather web application report.pdf
 
J.Yang, ICLR 2024, MLILAB, KAIST AI.pdf
J.Yang,  ICLR 2024, MLILAB, KAIST AI.pdfJ.Yang,  ICLR 2024, MLILAB, KAIST AI.pdf
J.Yang, ICLR 2024, MLILAB, KAIST AI.pdf
 
Student information management system project report ii.pdf
Student information management system project report ii.pdfStudent information management system project report ii.pdf
Student information management system project report ii.pdf
 
Water Industry Process Automation and Control Monthly - May 2024.pdf
Water Industry Process Automation and Control Monthly - May 2024.pdfWater Industry Process Automation and Control Monthly - May 2024.pdf
Water Industry Process Automation and Control Monthly - May 2024.pdf
 
Planning Of Procurement o different goods and services
Planning Of Procurement o different goods and servicesPlanning Of Procurement o different goods and services
Planning Of Procurement o different goods and services
 
WATER CRISIS and its solutions-pptx 1234
WATER CRISIS and its solutions-pptx 1234WATER CRISIS and its solutions-pptx 1234
WATER CRISIS and its solutions-pptx 1234
 
MCQ Soil mechanics questions (Soil shear strength).pdf
MCQ Soil mechanics questions (Soil shear strength).pdfMCQ Soil mechanics questions (Soil shear strength).pdf
MCQ Soil mechanics questions (Soil shear strength).pdf
 
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
 
Gen AI Study Jams _ For the GDSC Leads in India.pdf
Gen AI Study Jams _ For the GDSC Leads in India.pdfGen AI Study Jams _ For the GDSC Leads in India.pdf
Gen AI Study Jams _ For the GDSC Leads in India.pdf
 

Acc shams

  • 1. Abstract— The proposed PID tuning method has similar approach to the recently published paper of Shamsuzzoha and Skogestad (2010). It is one step procedure to obtain the PI/PID setting which gives the better performance and robustness. The method requires one closed-loop step setpoint response experiment using a proportional only controller with gain Kc0. On the bases of simulations for a range of first-order with delay processes, simple correlations have been derived to give PI/PID controller settings. The controller gain (Kc/Kc0) is only a function of the overshoot observed in the setpoint experiment. The controller integral and derivative time (τI and τD) is mainly a function of the time to reach the first peak (tp). The proposed tuning method shows better performance than Shamsuzzoha and Skogestad [1] for broad range of processes. I. INTRODUCTION He proportional, integral, and derivative (PID) controller is widely used in the process industries due to its simplicity, robustness and wide ranges of applicability in the regulatory control layer. One survey of Desborough and Miller [2] indicates that more than 97% of regulatory controllers utilize the PID algorithm. A recent survey of Kano and Ogawa [3] shows that the ratio of applications of different type of controller e.g., PID control, conventional advanced control and model predictive control is about 100:10:1. Although the PID controller has only three adjustable parameters, they are difficult to be tuned properly. One reason is that tedious plant tests are required to obtain improved controller setting. There are two approaches for the controller tuning and one may use open-loop or closed-loop plant tests. Most tuning approaches are based on open-loop plant information; typically the plant’s gain (k), time constant (τ) and time delay (θ). One popular approach is direct synthesis (Seborg et Manuscript received September 25, 2011. Acknowledgement: The authors would like to acknowledge the support (Project Number: SB101016) provided by the Deanship of Scientific Research at King Fahd University of Petroleum and Minerals (KFUPM). M. Shamsuzzoha is with the Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Daharan, 31261, Kingdom of Saudi Arabia, Phone: +966-3-860-7360, (email: mshams@kfupm.edu.sa) Moonyong Lee is with the School of Chemical Engineering and Technology, Yeungnam University, Kyongsan 712-749, Korea, Phone: +82-53-810-2512, (email: mynlee@ynu.ac.kr) Hiroya Seki is with the Chemical Resources Laboratory, Tokyo Institute of Technology, 4259-R1-19 Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan (e-mail: hseki@pse.res.titech.ac.jp) al.,[4]) and other is the IMC-PID tuning method of Rivera et al.[5]. Both the methods give very good performance for setpoint changes but sluggish responses to input (load) disturbances for lag-dominant (including integrating) processes with τ/θ>10. To improve load disturbance rejection, Skogestad [6] proposed the modified SIMC method where the integral time is reduced for processes with a large value of the time constant τ. The SIMC rule has one tuning parameter, the closed-loop time constant τc, and for “fast and robust” control is recommended to choose τc= θ, where θ is the (effective) time delay. However, these approaches require that one first obtains an open-loop model of the process and then tuning of the control loop. There are two problems here. First, an open-loop experiment, for example a step test, is normally needed to get the required process data. This may be time consuming and may upset the process and even lead to process runaway. Second, approximations are involved in obtaining the process parameters (e.g., k, τ and θ) from the data. The main alternative is to use closed-loop experiments. One approach is the classical method of Ziegler-Nichols [7] which requires very little information about the process. However, there are several disadvantages. First, the system needs to be brought its limit of instability and a number of trials may be needed to bring the system to this point. Another disadvantage is that the Ziegler-Nichols [7] tunings do not work well on all processes. It is well known that the recommended settings are quite aggressive for lag-dominant (integrating) processes (Tyreus and Luyben,[8]) and quite slow for delay-dominant process (Skogestad, [6]). A third disadvantage of the Ziegler-Nichols [7]) method is that it can only be used on processes for which the phase lag exceeds - 180 degrees at high frequencies. For example, it does not work on a simple second-order process. Recently, Shamsuzzoha and Skogestad [1] have developed new procedure for PI/PID tuning method in closed-loop mode. Their method is based on the SIMC tuning rule and provides satisfactory result for both the performance and robustness. For the PID tuning parameter they need to repeat the experiment with PD controller on the basis of the prior information obtain from P controller test. They recommended adding the derivative action only for dominant second-order process. Closed-loop PI/PID Controller Tuning for Stable and Unstable Processes M.Shamsuzzoha*, Moonyong Lee, Hiroya Seki T 2012 American Control Conference Fairmont Queen Elizabeth, Montréal, Canada June 27-June 29, 2012 978-1-4577-1096-4/12/$26.00 ©2012 AACC 2368
  • 2. Therefore, it is important to have other tuning method based on the closed-loop experiment which gives better performance and robustness. In this method it is simple to obtain the PID tuning parameters in one step for improved performance while satisfying the other concern during the closed-loop experiment like reduces the number of trails, and works for a wide range of processes. IMC-PID Controller Tuning Rule The motivation of this section is to develop IMC-PID controller tuning for first order process with delay. In process control, a first-order process with time delay is a common representation of the process dynamics: - ( ) 1 s ke g s s θ τ = + (1) Here k is the process gain, τ lag time constant and θ the time delay. Most processes in the chemical industries can be satisfactorily controlled using a PID controller: ( ) 1 1c D I c s K s s τ τ   = + +    (2) The other structure of the PID controller like series form of PID can easily be transform from Eq. (2). The conventional feedback controller which is equivalent to the IMC controller can be expressed by following relation. ( ) 1 q c s gq = − % (3) where g% denotes the process transfer function, c and q are the conventional and IMC controller, respectively. The IMC controller is designed in two steps: Step 1: The process model g% is decomposed into two parts: M Ag p p=% (4) where pm and pA are the portions of the model inverted and not inverted, respectively, by the controller (pA is usually a non-minimum phase and contains dead times and/or right half plane zeros); pA(0)=1. Step 2: The IMC controller is designed by -1 Mq p f= (5) The IMC filter f is usually given as 1( 1)r cf sτ= + and cτ is an adjustable parameter which controls the tradeoff between the performance and robustness; r is selected to be large enough to make the IMC controller semi-proper. Consider approximation of the dead time term in Eq. (1) by first order Pade approximation: ( ) 1- 2 ( ) 1 1 2 k s g s s s θ θ τ      =   + +    (6) The resulting IMC-PID tuning formula after simplification is obtain in Eq.(7) for the given process in Eq. (1). ( ) 2 2 c c K k τ θ τ θ + = + (7a) 2 I c θ τ τ= + (7b) 2 D τθ τ τ θ = + (7c) The PID controller designed on the basis of the IMC principle provides excellent set-point tracking, but has a sluggish disturbance response, especially for processes with a small θ/τ ratio [4,6,9]. To improve the load disturbance response Skogestad [6] recommended modifying the integral time as I cτ =4(τ +θ) (8) Therefore, the integral time in Eq.(7b) is modified for the improved disturbance I cτ =min , 4(τ +θ) 2 c θ τ    +      (9) τc= θ has been recommend which gives maximum sensitivity (Ms)=1.70 approximately. The revised tuning method for the PID controller tuning is given as: 2 3 cK k τ θ θ + = (10a) min , 8 2 I θ τ τ θ    = +      (10b) 2 D τθ τ τ θ = + (10c) I. CLOSED-LOOP EXPERIMENT This section is devoted for the development of the PI/PID controller based on the closed-loop data which resembles the proposed tuning method in Eq.(10). The simplest closed- loop experiment is probably a setpoint step response (Fig. 1) where one maintains full control of the process, including the change in the output variable. The simplest to observe is the time tp to reach the (first) overshoot and its magnitude, and this information is therefore the basis for the proposed method. The proposed procedure is as follows (Shamsuzzoha and Skogestad, [1]): 1. Switch the controller to P-only mode (for example, increase the integral time τI to its maximum value or set the integral gain KI to zero). In an industrial system, with bumpless transfer, the switch should not upset the process. 2. Make a setpoint change that gives an overshoot between 0.10 (10%) and 0.60 (60%); about 0.30 (30%) is a good value. Record the controller gain Kc0 used in the experiment. Most likely, unless the original controller was quite tightly tuned, one will need to increase the controller gain to get a sufficiently large overshoot. Note that small overshoots (less than 0.10) are not considered because it is difficult in practice to obtain from experimental data accurate values of the overshoot and peak time if the overshoot is too small. Also, large overshoots (larger than about 0.6) give a long settling time and require 2369
  • 3. more excessive input changes. For these reasons we recommend using an “intermediate” overshoot of about 0.3 (30%) for the closed-loop setpoint experiment. 3. From the closed-loop setpoint response experiment, obtain the following values (see Fig. 1): • Fractional overshoot, (∆yp - ∆y∞) /∆y∞ • Time from setpoint change to reach peak output (overshoot), tp • Relative steady state output change, b = ∆y∞/∆ys. Here the output variable changes are: ∆ys: Setpoint change ∆yp: Peak output change (at time tp) ∆y∞: Steady-state output change after setpoint step test To find ∆y∞ one needs to wait for the response to settle, which may take some time if the overshoot is relatively large (typically, 0.3 or larger). In such cases, one may stop the experiment when the setpoint response reaches its first minimum and record the corresponding output, ∆yu. ∆y∞ = 0.45(∆yp + ∆yu) (11) The details about how to obtaining Eq.(11) is given in Shamsuzzoha and Skogestad (2010). II. CORRELATION BETWEEN SETPOINT RESPONSE AND THE IMC-PID-SETTINGS The objective of this paper is to provide a one step procedure in closed-loop for controller tuning similar to the Shamsuzzoha and Skogestad (2010) and Ziegler-Nichols (1942) method. Thus, the goal is to derive a correlation, preferably as simple as possible, between the setpoint response data (Fig. 1) and the Proposed PID settings in Eq. (10), initially with the choice τc=θ. For this purpose, we considered 15 first-order with delay models g(s)=ke-θs /(τs+1) that cover a wide range of processes; from delay-dominant to lag-dominant (integrating): τ/θ=0.1,0.2,0.4,0.8,1.0,1.5,2.0,2.5,3.0,7.5,10.0,20.0,50.0,100 Since we can always scale time with respect to the time delay (θ) and since the closed-loop response depends on the product of the process and controller gains (kKc) we have without loss of generality used in all simulations k=1 and θ=1. For each of the 15 process models (values of τ/θ), we obtained the PID-settings using Eq. (10) with the choice τc=θ. Furthermore, for each of the 15 processes we generated 6 closed-loop step setpoint responses using P-controllers that give different fractional overshoots. Overshoot= 0.10, 0.20, 0.30, 0.40, 0.50 and 0.60 In total, we then have 90 setpoint responses, and for each of these we record four data: the P-controller gain Kc0 used in the experiment, the fractional overshoot, the time to reach the overshoot (tp), and the relative steady-state change, b = ∆y∞/∆ys. Controller gain (Kc). We first seek a relationship between the above four data and the corresponding proposed controller gain Kc. Indeed, as illustrated in Fig. 2, where we plot kKc as a function of kKc0 for the 90 setpoint experiments, the ratio Kc/Kc0 is approximately constant for a fixed value of the overshoot, independent of the value of τ/θ. Thus, we can write c c0 K =A K (12) py∆ pt y∞∆ sy∆ t 0t = θ uy∆ sy∆ Fig. 1. Closed-loop step setpoint response with P-only control. 0 20 40 60 80 100 120 0 10 20 30 40 50 60 70 kKc0 kKc 0.10 overshoot kK c =1.1621kK c0 0.20 overshoot kK c =0.9701kK c0 0.30 overshoot kK c =0.841kK c0 0.40 overshoot kK c =0.7453kK c0 0.50 overshoot kK c =0.6701kK c0 0.60 overshoot kK c =0.6083kK c0 Fig. 2. Relationship between P-controller gain kKc0 used in setpoint experiment and corresponding proposed controller gain (Eq. 10a) kKc. where the ratio A is a function of the overshoot only. In Fig. 3 we plot the value of A, which is obtained as the best fit of the slopes of the lines in Fig. 2, as a function of the overshoot. The following equation (solid line in Fig. 3) fits the data in Fig. 2 well and given as: A=[1.55(overshoot)2 -2.159 (overshoot)+1.35] (13) 2370
  • 4. 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 overshoot (fractional) A y = 1.55*(overshoot)2 - 2.159*(overshoot) + 1.35 Fig. 3. Variation of A with overshoot using data (slopes) from Fig. 2. 0.1 0.3 0.5 0.6 0 0.1 0.2 0.3 0.4 0.5 Overshoot θ/tp 0.43 (τI1 ) 0.305 (τI2 ) τ/θ=0.1 τ/θ=8 τ/θ=100 τ/θ=1 Fig. 4. Ratio between delay and setpoint overshoot peak time (θ/tp) for P- only control of first-order with delay processes (solid lines); Dotted lines: values used in final correlations, Shamsuzzoha and Skogestad (2010). Integral time (τI). It is interesting to find a simple correlation for the integral time. The proposed method in Eq. (10b) uses the minimum of two values, it seems reasonable to look for a similar relationship, that is, to find one value (τI1 =τ) for processes with a relatively large delay, and another value (τI2 =8θ) for processes with a relatively small delay including integrating processes. (1) Process with relatively large delay: This case arise when processes have a relatively large delay i.e., τ/θ<8, the integral action in the proposed tuning rule is to use τI = (τ+ θ/2). Rearrangement of Eq.(10a) is given as 3 2 ckK θ θ τ − = (14) Adding both the side θ/2 in Eq.(14) and substitute (τ+ θ/2)=τI, we get I 1.5 ckKτ θ= (15) In Eq. (15), we also need the value of the process gain k, and to this effect write kKc= kKc0.Kc/ Kc0 (16) Here, the value of the loop gain kKc0 for the P-control setpoint experiment is given from the value of b: c0 b kK = (1-b) (17) Substituting kKc from Eq. (17) and Kc/ Kc0=A into Eq. (15) and given as I b 1.5A (1-b) τ θ= (18) To prove this, the closed-loop setpoint response is ∆y/∆ys = gc/(1+gc) and with a P-controller with gain Kc0, the steady- state value is ∆y∞/∆ys = kKc0/(1+kKc0)=b and we derive Eq.(17). The absolute value is included to avoid problems if b>1, as may occur for an unstable process or because of inaccurate data. It is possible to obtain the value of time delay θ directly from the closed-loop setpoint response, but usually this is not always easy task. The reasonable correlation has been developed by Shamsuzzoha and Skogestad [1] for the θ and the setpoint peak time tp which is easier to observe. For processes with a relatively large time delay (τ/θ<8), the ratio θ/tp varies between 0.27 (for τ/θ= 8 with overshoot=0.1) and 0.5 (for τ/θ=0.1 with all overshoots). For the intermediate overshoot of 0.3, the ratio θ/tp varies between 0.32 and 0.50. A conservative choice would be to use θ=0.5tp because a large value increases the integral time. However, to improve performance for processes with smaller time delays, we propose to use θ=0.43tp which is only 14% lower than 0.50 (the worst case). In summary, we have for process with a relatively large time delay: 0.645 (1- ) I p b A t b τ = (19) (2) Process with relatively small delay. Shamsuzzoha and Skogestad [1] method and in this proposed tuning rule have same integral action for the lag-dominant process. The integral time for a lag-dominant (including integrating) process with τ/θ>8 the proposed tuning rule for integral time gives τI2=8θ (20) For τ/θ>8 we see from Fig. (4) that the ratio θ/tp varies between 0.25 (for τ/θ=100 with overshoot=0.1) and 0.36 (for τ/θ=8 with overshoot 0.6). We select to use the average value θ= 0.305tp which is only 15% lower than 0.36 (the worst case). Also note that for the intermediate overshoot of 0.3, the ratio θ/tp varies between 0.30 and 0.32. In summary, we have for a lag-dominant process I2 pτ =2.44t (21) Conclusion. Therefore, the integral time τI is obtained as the minimum of the above two values: I pτ =min 0.645 , 2.44t (1- ) p b A t b        (22) 2371
  • 5. Derivative action (τD): Although a significant number of the PID controllers switched off their derivative part but proper use of derivative action can increase stability and improve the closed-loop performance. The derivative action is very important for slow moving loops where overshoot is undesirable e.g., temperature loop. The motivation of this section is to develop the approach for inclusion of the derivative action from closed-loop data. In the proposed study the derivative action is recommended for the process having 1τ θ ≥ which can give performance improvement. Substitute the value of 0.5Iτ τ θ= − into 1τ θ ≥ and after rearrangement the resulting equation is ( )0.5 1Iτ θ θ − ≥ (23) After simplification it is 1.5Iτ θ ≥ and resulting constrain is 1.0ckK ≥ . The corresponding closed-loop condition for the derivative action is given as: ( ) b A 1 1-b ≥ (24) Case I: For approximately integrating process (τ>> θ), where integral time is τI =8θ and in the closed-loop the time delay θ= 0.305tp. The derivative time τD1 in Eq. (10c) can be approximated as 1 0.305 0.15 2 2 2 p D p t t τθ θ τ τ ≈ = = = (25) Case II: The processes with a relatively large delay, for this case integral time τI=(τ+0.5θ) and time delay in closed-loop is θ=0.43tp. For such cases the derivative action is recommended only if τ/θ ≥ θ. Assuming the case when τ=θ the τD2 is given from Eq. (10c) as 2 2 2 0.43 0.1433 2 3 3 3 p D p t t θ θ θ τ θ θ θ ≈ = = = = + (26) The derivative action is only recommended for the process having 1τ θ ≥ and in the closed-loop this criteria is ( ) b A 1 1-b ≥ . Summary: The derivative action for both the cases i.e., τD1 and τD2 are approximately same and the conservative choice for the selection of τD is given as ( ) 0.14 1 1- D p b t if A b τ = ≥ (27) Selection of Proportional Controller Gain (Kc0): An overshoot of around 0.3 is recommended for the proposed study. Sometimes achieving the P-controller gain (Kc0) via trial and error which gives the overshoot around 0.3 can be time consuming. Therefore, an effective approach to get the value of Kc0 which gives the overshoot around 0.3 is very significant for the proposed method. It is important to note that this procedure requires initial information of the first closed-loop experiment. Let’s assume for the first closed-loop test P- controller gain of Kc01 is applied and resulting overshoot OS1 is achieved that is between 0.1 to 0.60 but not around 0.30. Let the target overshoot be OS and the target P-controller gain be Kc0. In the proposed closed-loop tuning method the goal is to match the performance with IMC-PID tuning rule and for this only maintains a constant P gain Kc, regardless of the overshoot that resulted from the closed-loop setpoint test. Ideally, Kc should be the same as that determined with different overshoots from various closed-loop setpoint test and the resulting correlation is given as: ( ) ( ) ( ) ( )2 2 1 1 01 01.55 OS 2.159 OS 1.35 1.55 OS 2.159 OS 1.35c cK K   − + = − +       (28) The above Eq.(28) gives a general guideline for choosing the P-controller gain for the next closed-loop setpoint test. As it is mentioned earlier the proposed method is good agreement with the IMC-PID for the overshoot around 0.3. Therefore the overshoot in Eq.(28) is set as 0.3 and after simplification the gain for the next closed-loop test is recommended as: ( ) ( )( )2 0 1 1 011.19 1.45 OS 2.02 OS 1.27c cK K= − + (29) It is important to note that we are not keen to achieve the precise fractional overshoot of 0.3, so few trial is sufficient to achieve the desire overshoot around 0.3 from above equation. III. SIMULATION The proposed closed-loop tuning method has been tested on broad class of the process model. It provides the acceptable controller setting for all cases with respect to both the performance and robustness. To show the effectiveness of the proposed method two cases have been shown as a representative example i.e., integrating with time delay and higher order process with time delay. The simulation has been conducted for three different overshoot (around 0.1, 0.3 and 0.6) and are compared with the recently reported method of Shamsuzzoha and Skogestad[1]. Example 1: ( ) ( )( ) 2 1 6 1 2 1 s s e s s − − + + + Example 2: s e s − Figure 5 and 6 presents a comparison of the proposed method with Shamsuzzoha and Skogestad [1] by introducing a unit step change in the set-point at t = 0 and an unit step change of load disturbance (at t = 100 for Example 1 and t = 50 for Example 2) at plant input. It is clear from Figure 5 and 6 that the proposed method gives better closed-loop response for both the high order and integrating processes. There are significant performance improvements in both the case for the disturbance rejection while maintaining setpoint performance. The overshoot around 0.1 typically gives slower and more robust PID-settings, whereas a large overshoot around 0.6 2372
  • 6. gives more aggressive PID-settings. It is good because a more careful step response results in more careful tunings settings. 0 50 100 150 200 0.2 0.6 1 1.4 time OUTPUTy Shamsuzzoha and Skogestad method with F=1(overshoot=0.119) Shamsuzzoha and Skogestad method with F=1 (overshoot=0.344) Shamsuzzoha and Skogestad method with F=1(overshoot=0.608) Proposed method with F=1 (overshoot=0.119) Proposed method with F=1 (overshoot=0.344) Proposed method with F=1 (overshoot=0.608) Fig. 5. Responses for PID-control of high order process ( ) ( )( )2 1 6 1 2 1 s s e s s − − + + + , Setpoint change at t=0; load disturbance of magnitude 1 at t=100. IV. CONCLUSION A simple approach has been developed for PI/PID controller tuning by the closed-loop setpoint step using a P-controller with gain Kc0. The PID-controller settings are then obtained directly from following three data from the setpoint experiment: • Overshoot, (∆yp - ∆y∞) /∆y∞ • Time to reach overshoot (first peak), tp • Relative steady state output change, b = ∆y∞/∆ys. If one does not want to wait for the system to reach steady state, one can use the estimate ∆y∞ = 0.45(∆yp + ∆yu). The proposed tuning PID tuning method is: c c0K =K A I pτ =min 0.645 , 2.44t (1- ) p b A t b        ( ) 0.14 1 1- D p b t if A b τ = ≥ where, A=[1.55(overshoot)2 -2.159 (overshoot)+1.35] The proposed method works well for a wide variety of the processes typical for process control, including the standard first-order plus delay processes as well as integrating, high- order, inverse response, unstable and oscillating process. 0 10 20 30 40 50 60 70 80 90 100 0 0.5 1 1.5 2 2.5 3 time OUTPUTy Shamsuzzoha and Skogestad method with F=1 (overshoot=0.108) Shamsuzzoha and Skogestad method with F=1 (overshoot=0.302) Shamsuzzoha and Skogestad method with F=1 (overshoot=0.60) Proposed method with F=1 (overshoot=0.108) Proposed method with F=1 (overshoot=0.302) Proposed method with F=1 (overshoot=0.60) Fig. 6. Responses for PID-control of integrating processes s e s− , Setpoint change at t=0; load disturbance of magnitude 1 at t=50. V. REFERENCES [1] M. Shamsuzzoha, S. Skogestad, “The setpoint overshoot method: A simple and fast closed-loop approach for PID tuning”, Journal of Process Control, vol.20, pp.1220–1234,(2010). [2] L. D. Desborough, R. M. Miller, “Increasing customer value of industrial control performance monitoring—Honeywell’s experience”. Chemical Process Control–VI (Tuscon, Arizona, Jan. 2001), AIChE Symposium Series No. 326. Volume 98, USA (2002). [3] M. Kano, M. Ogawa, “The state of art in chemical process control in Japan: Good practice and questionnaire survey, Journal of Process Control, (20), pp.969-982, (2010). [4] D. E. Seborg, T. F. Edgar, D. A. Mellichamp, “Process Dynamics and Control”, 2nd ed., John Wiley & Sons, New York, U.S.A, (2004). [5] D. E. Rivera, M. Morari, S. Skogestad, “Internal model control. 4. PID controller design”, Ind. Eng. Chem. Res., vol.25 (1) pp. 252– 265, (1986). [6] S. Skogestad, “Simple analytic rules for model reduction and PID controller tuning”, Journal of Process Control, vol.13, pp.291– 309, (2003). [7] J. G. Ziegler, N. B. Nichols, “Optimum settings for automatic controllers”, Trans. ASME, vol. 64, pp.759-768, (1942). [8] B. D. Tyreus, W. L. Luyben, “Tuning PI controllers for integrator/dead time processes”, Ind. Eng. Chem. Res. pp.2628– 2631, (1992). [9]M. Shamsuzzoha, M. Lee, “IMC-PID controller design for improved disturbance rejection” Ind. Eng. Chem. Res, vol. 46, No. 7, 2007, pp. 2077-2091. 2373