Journal of Applied Research and Technology
www.jart.icat.unam.mx
Journal of Applied Research and Technology 17 (2019) 313-325
Venkatachalam Veeraragavana*, Prabhakaran Duraisamyb, Ramakrishnan Krishnanc
𝑥̇(𝑡) = 𝐴𝑥(𝑡) + 𝐴𝑑𝑥(𝑡 − 𝜏(𝑡)), 𝑡 > 0
𝑥(𝑡) = ∅(𝑡), ∀𝑡 ∈ [−𝜏̅, 0], 𝜏̅ > 0
𝜏(𝑡)
𝜏̅ 𝜇
;
0 1 0 0
1 0 0
0 1 0
0 0 1 0
−
−
−
=
F F
F H H
H V
T T K T T K T
A
− −
=
0 0 0 0
0 0 0 0
0 0 0 0
0 0
V V I V
V P
d
T K K T
K K
A
𝑥(𝑡) 𝑥(𝑡 − 𝜏(𝑡))
0 ≤ 𝜏(𝑡) ≤ 𝜏̅, 𝜏̇(𝑡) ≤ 𝜇, ∀𝑡 ≥ 0
𝑥(𝑡) ∈ ℝ4×1 𝐴 ∈ ℝ4×4
𝐴𝑑∈ ℝ4×4 ∅(𝑡)
𝜏̅ 𝑎𝑛𝑑 𝜇
[𝑅 𝑆
𝑆𝑇 𝑅] ≥ 0; 𝑃 > 0; 𝑄𝑖> 0, 𝑖 = 1,2; 𝑅 > 0 𝛱 < 0.
𝛱 = 𝑒1𝑃𝑒4𝑇+ 𝑒4𝑃𝑒1𝑇+ 𝑒1(𝑄1+ 𝑄2)𝑒1𝑇+ 𝑒2(−(1𝜇)𝑄1)𝑒2𝑇
− 𝑒3𝑄2𝑒3𝑇+ 𝑒4(𝜏2𝑅)𝑒4𝑇
− [𝑒2𝑇− 𝑒3𝑇
𝑒1𝑇− 𝑒2𝑇]
𝑇
[𝑅 𝑆
𝑆𝑇 𝑅] [𝑒2𝑇− 𝑒3𝑇
𝑒1𝑇− 𝑒2𝑇]
𝑒1= [𝐼 0 0]𝑇, 𝑒2= [0 𝐼 0]𝑇, 𝑒3= [0 0 𝐼]𝑇, 𝑒4= (𝐴𝑒1𝑇+ 𝐴𝑑𝑒2𝑇)𝑇.
𝑉1(𝑡) = 𝑥𝑇(𝑡)𝑃𝑥(𝑡)
𝑉2(𝑡) = ∫𝑡−𝜏(𝑡)𝑡 𝑥𝑇(𝑠)𝑄1𝑥(𝑠)𝑑𝑠+ ∫𝑡−𝜏𝑡 𝑥𝑇(𝑠)𝑄2𝑥(𝑠)𝑑𝑠
𝑉3(𝑡) = 𝜏 ∫ ∫−𝜏0 𝑡+𝜃𝑡 𝑥̇𝑇(𝑠)𝑅𝑥̇(𝑠)𝑑𝑠𝑑𝜃
𝑃, 𝑄𝑖, 𝑖 = 1,2, 𝑅
η(t)= [xT(t) xT(t-τ(t)) xT(t-τ)]T
𝑉𝑖(𝑡), 𝑖 = 1,2,3
𝑉1(𝑡)
𝑉̇1(𝑡) = 𝑥̇𝑇(𝑡)𝑃𝑥(𝑡) + 𝑥𝑇(𝑡)𝑃𝑥̇(𝑡),
𝑉̇1(𝑡) = 𝜂𝑇(𝑡)(𝑒4𝑃𝑒1𝑇+ 𝑒1𝑃𝑒4𝑇)𝜂(𝑡)
𝑉2(𝑡)
𝑉̇2(𝑡) = 𝑥𝑇(𝑡)(𝑄1+ 𝑄2)𝑥(𝑡) − (1 − 𝜏̇(𝑡))𝑥𝑇
(𝑡 − 𝜏(𝑡))𝑄1𝑥(𝑡 − 𝜏(𝑡)) − 𝑥𝑇(𝑡 − 𝜏)𝑄2𝑥(𝑡 − 𝜏)
𝜏̇(𝑡) ≤ 𝜇 < 1, 𝑉̇2(𝑡)
𝑉̇2(𝑡) ≤ 𝑥𝑇(𝑡)(𝑄1+ 𝑄2)𝑥(𝑡) − (1 − 𝜇)𝑥𝑇(𝑡 − 𝜏(𝑡))𝑄1𝑥
(𝑡 − 𝜏(𝑡)) − 𝑥𝑇(𝑡 − 𝜏)𝑄2𝑥(𝑡 − 𝜏) (12)
𝑉̇2(𝑡) ≤ 𝜂𝑇(𝑡)(𝑒1(𝑄1+ 𝑄2)𝑒1𝑇)𝜂(𝑡) − 𝜂𝑇(𝑡)
(𝑒2(1 − 𝜇)𝑄1𝑒2𝑇)𝜂(𝑡) − 𝜂𝑇(𝑡)(𝑒3𝑄2𝑒3𝑇)𝜂(𝑡)
𝑉3(𝑡)
𝑉̇3(𝑡) = 𝑥̇𝑇(𝑡)(𝜏2𝑅)𝑥̇(𝑡) − 𝜏 ∫𝑡−𝜏𝑡 𝑥̇𝑇(𝑠)𝑅𝑥̇(𝑠)𝑑𝑠.
𝑉̇3(𝑡) ≤ 𝜂𝑇(𝑡) ((𝑒4(𝜏2𝑅)𝑒4𝑇) −
[𝑒2𝑇− 𝑒3𝑇 𝑒1𝑇− 𝑒2𝑇]
𝑇
[𝑅 𝑆
𝑆𝑇 𝑅] [𝑒2𝑇− 𝑒3𝑇
𝑒1𝑇− 𝑒2𝑇]) 𝜂(𝑡)
[𝑅 𝑆
𝑆𝑇 𝑅] ≥ 0.
𝑉𝑖(𝑡)
𝑉̇(𝑡) ≤ ∑3𝑖=1𝑉𝑖(𝑡)
𝑉̇(𝑡) ≤ 𝜂𝑇(𝑡)𝛱𝜂(𝑡) 𝛱 < 0,
𝑥̇(𝑡) = 𝐴𝑥(𝑡) + 𝐴𝑑𝑥(𝑡 − 𝜏(𝑡)) + 𝑓(𝑥(𝑡), 𝑡)
+𝑔(𝑥(𝑡 − 𝜏(𝑡)), 𝑡), 𝑥(𝑡) = ∅(𝑡), ∀𝑡 ∈ [−𝜏̅, 0], 𝜏̅ > 0
𝐴, 𝐴𝑑, 𝜏(𝑡) ∅(𝑡)
𝑓(𝑥(𝑡), 𝑡) 𝑔(𝑥(𝑡 − 𝜏(𝑡)), 𝑡)
𝑓(0, 𝑡) = 𝑔(0, 𝑡) = 0
𝑓𝑇(. )𝑓(. ) ≤ 𝛼2𝑥𝑇(𝑡)𝐹𝑇𝐹𝑥(𝑡)
𝑔𝑇(. )𝑔(. ) ≤ 𝛽2𝑥𝑇(𝑡 − 𝜏(𝑡))𝐺𝑇𝐺𝑥(𝑡 − 𝜏(𝑡)),
‖𝑓(. )‖ ≤ 𝛼‖𝑥(𝑡)‖ + 𝛽‖𝑥(𝑡 − 𝜏(𝑡))‖
𝛼 ≥ 0 𝛽 ≥ 0
𝑓𝑇(. )𝑓(. ) ≤ 𝛼2𝑥𝑇(𝑡)𝐹𝑇𝐹𝑥(𝑡)
+𝛽2𝑥𝑇(𝑡 − 𝜏(𝑡))𝐺𝑇𝐺𝑥(𝑡 − 𝜏(𝑡))
𝐹 𝐺
𝛼 𝛽
𝑃, 𝑄𝑖, 𝑖 = 1, 2, 𝑅 𝜀 ≥
0; 𝑆
[𝑅 𝑆
𝑆𝑇 𝑅] ≥ 0;
𝑃 > 0; 𝑄𝑖> 0, 𝑖 = 1,2; 𝑅 > 0 𝛱̅ < 0.
𝛱̅ = 𝑒̅1𝑃𝑒̅5𝑇+ 𝑒̅5𝑃𝑒̅1𝑇+ 𝑒̅1(𝑄1+ 𝑄2+ 𝜖𝛼2𝐹𝑇𝐹)𝑒̅1𝑇
+𝑒̅2(−(1 − 𝜇)𝑄1+ 𝜖𝛽2𝐺𝑇𝐺)𝑒̅2𝑇− 𝑒̅3𝑄2𝑒̅3𝑇− 𝑒̅4(𝜖𝐼)𝑒̅4𝑇
+𝑒̅5(𝜏2𝑅)𝑒̅5𝑇− [𝑒̅2𝑇− 𝑒̅3𝑇 𝑒̅1𝑇− 𝑒̅2𝑇]
𝑇
[𝑅 𝑆
𝑆𝑇 𝑅] [𝑒̅2𝑇− 𝑒̅3𝑇 𝑒̅1𝑇− 𝑒̅2𝑇]
0 0 0
,, 0 0 0
, 0 0 0
, 0 0 0
4 3 2 1
T T T T
I e
I e
I e
I e
=
=
=
=
𝑒̅5= (𝐴𝑒̅1𝑇+ 𝐴𝑑𝑒̅2𝑇+ 𝑒̅4𝑇)𝑇.
𝑥̇(𝑡) = [𝐴 + ∆𝐴(𝑡)]𝑥(𝑡) + [𝐴𝑑+ ∆𝐴𝑑(𝑡)]𝑥(𝑡 − 𝜏(𝑡))
𝑥(𝑡) = ∅(𝑡), ∀𝑡 ∈ [−𝜏̅, 0], 𝜏̅ > 0.
∆𝐴(𝑡), ∆𝐴𝑑(𝑡)
𝐴(𝑡) 𝐴𝑑(𝑡)
[∆𝐴(𝑡) ∆𝐴𝑑(𝑡)] = 𝐷 𝐹(𝑡)[𝐸𝑎 𝐸𝑏]
𝐹𝑇(𝑡)𝐹(𝑡) ≤ 𝐼, ∀𝑡
𝐹(𝑡)
𝐷, 𝐸𝑎, 𝐸𝑏
𝐹(𝑡)
𝜏 > 0, 𝜇 > 0,
𝜏(𝑡)
𝜏̅ > 0 𝜇 > 0
[𝑅 𝑆
𝑆𝑇 𝑅] ≥ 0; 𝑃 > 0; 𝑄𝑖> 0, 𝑖 = 1,2; 𝑅 > 0
0
*
*
*
*
*
0
*
*
*
*
0
*
*
*
0 0
0
*
*
0 2
) 1
* (
~
2 2 2
1 2
2 2
1
−
−
−
−
− + − +
−
−
−
−
− + +
+ +
=
I I
RD R
R Q
E R
A S R S S R
Q
E PD R A S S R PA R Q
Q PA P A
T b T
d T T
T a T
T T d T
𝛱 <
0 𝐴 𝐴𝑑
∆𝐴(𝑡) = 𝐴 + 𝐷𝐹(𝑡)𝐸𝑎 ∆𝐴𝑑 = 𝐴𝑑 + 𝐷𝐹(𝑡)𝐸𝑏 𝛱 < 0
𝛱 + 𝛱𝑢+ 𝛱𝑢𝑇 < 0
,
0
*
*
*
0 0
*
*
) ) ( 0 (
0
*
) ) ( 0 (
) ) ( ( ) ) ( (
) ) ( (
2 2
+
=
+
R E t DF
R E t E DF
t DF P E t DF P
P E t DF
T b
T a b
a T a u T u
𝛱𝑢 𝛱𝑢= 𝐻𝐹(𝑡)𝐸.
𝛱 + 𝐻𝐹(𝑡)𝐸 + (𝐻𝐹(𝑡)𝐸)𝑇< 0
𝑃,𝑄max1,𝑄2,𝑅𝜏
[𝑅 𝑆
𝑆𝑇 𝑅] ≥ 0; 𝑃 > 0; 𝑄𝑖> 0, 𝑖 = 1,2; 𝑅 > 0 𝛱 < 0
𝐾𝐻= 34 𝜏𝐻= 30
𝐾𝑉= 1.25 𝜏𝑉= 3
𝐾𝐹= 0.08 𝜏𝐹= 2
) 1
( = +
s s K G
V V
V () 1
= + s s K G
H H
H
) 1
( = +
s s K G
F F
F
) (t
e−s
− +
PI Controller Law
Communication
delay Valve
Heat Exchanger
Sensor )
ref(s
)
s(s
)
h(s
)
e(s
v(s)
Controller s KP+KI
𝜏̅
𝑥̇(𝑡) = (𝐴 + 𝐴𝑑)𝑥(𝑡)
(𝐴 + 𝐴𝑑) 𝑃𝐼 −
𝑗𝜔
𝐾𝐼
𝐾𝐼 𝐾𝑃
∆𝜃𝐻(𝑡)
𝐾𝐼
𝑲𝑷 𝑲𝑰
(𝑨 + 𝑨𝒅)
±
±
±
±
±
±
±
±
±
𝐾𝑃 & 𝐾𝐼) 𝜏̅
𝐾𝑃= 0.75 𝐾𝐼= 0.05, 𝜇 = 0.05
𝜏̅
0 5 10 15 20 25 30 35 40 45 50
-30 -20 -10 0 10 20 30 40 50
t sec
output temperature
Responses of thermal control system for three different values of time-delays (Kp= 0.75: KI=0.05: =0.5)
=8.6
=9
=8.6801
1 2 3 4 5 6 7
0 1 2 3 4 5 6 7 8
Delay bounds for thermal system with nonlinealy laod perturbation
Kp
max
UnStable Region
stable region
==0, K I= 0.05
=0.025, =0, KI= 0.05
==0.025, KI= 0.05 𝐾𝑃
𝐾𝑃, 𝛼 𝑎𝑛𝑑 𝛽
𝝁 = 𝟎. 𝟎𝟓 𝝁 = 𝟎. 𝟏𝟎 𝝁 = 𝟎. 𝟐𝟎 𝝁 = 𝟎. 𝟑𝟎 𝝁 = 𝟎. 𝟓𝟎 𝑲𝑷= 𝟎. 𝟕𝟓
𝑲𝑰= 𝟎. 𝟎𝟓
𝑲𝑷= 𝟏 . 𝟎 𝑲𝑰= 𝟎. 𝟎𝟓
𝑲𝑷= 𝟏 . 𝟐𝟎 𝑲𝑰= 𝟎. 𝟎𝟓
𝑲𝑷= 𝟎. 𝟕𝟓 𝑲𝑰= 𝟎. 𝟎𝟕𝟓
𝑲𝑷= 𝟐. 𝟎 𝑲𝑰= 𝟎. 𝟎𝟏
𝑲𝑷= 𝟏 𝑲𝑰= 𝟎. 𝟏𝟓
𝑲𝑷= 𝟑. 𝟎 𝑲𝑰= 𝟎. 𝟏
𝑲𝑷= 𝟓. 𝟎 𝑲𝑰= 𝟎. 𝟎𝟓
μ
0.1𝐼𝑛
𝑛 𝑥(𝑡)
𝜏
𝛼 𝛽
𝐾𝑃 𝐾𝐼
𝛼 𝛽
𝐾𝑃 (1 − 7) 𝐾𝐼= 0.05, 𝜇 = 0.8
𝜏̅
𝛼 = 𝛽 = 0; 𝛼 = 0.025, 𝛽 = 0; 𝛼 = 𝛽 = 0.025
𝜏
𝜏𝑉𝑚𝑎𝑥
𝐾𝑃 𝐾𝐼
𝜏𝑉𝑚𝑎𝑥
𝜏̅
𝑲𝑷 𝑲𝑰 𝜶 = 𝜷 = 𝟎
𝜇 = 0.05 𝜇 = 0.10 𝜇 = 0.20 𝜇 = 0.30 𝜇 = 0.50
𝜏̅
𝑲𝑷 𝑲𝑰 𝜶 = 𝟎. 𝟎𝟐𝟓; 𝜷 = 𝟎
𝜇 = 0.05 𝜇 = 0.10 𝜇 = 0.20 𝜇 = 0.30 𝜇 = 0.50
𝜏̅
𝑲𝑷 𝑲𝑰 𝜶 = 𝟎. 𝟎𝟐𝟓; 𝜷 = 𝟎. 𝟎𝟐𝟓
𝜇 = 0.05 𝜇 = 0.10 𝜇 = 0.20 𝜇 = 0.30 𝜇 = 0.50
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
5.5 6 6.5 7 7.5 8 8.5 9
Delay bounds for Temperature control system with parametric uncertainty
v
max
-maximum delay margin
Kp=0.75, KI=0.05, =0.10 Kp=1.0, KI=0.05, =0.10 Kp=1.20, K
I=0.05, =0.10
system under different parametric uncertainties.
The deduced result of this work is more realistic in operating conditions in real time temperature control system.
acknowledgement Dr. K. Ramakrishnan (Associate Professor of Electrical and Electronics Engineering, Pondicherry Engineering College, Pondicherry, India) and Dr.
𝝉𝑽𝒎𝒂𝒙= 𝟎. 𝟐𝟎 𝝉𝑽𝒎𝒂𝒙= 𝟎. 𝟒𝟎 𝝉𝑽𝒎𝒂𝒙= 𝟎. 𝟔𝟎 𝝉𝑽𝒎𝒂𝒙= 𝟎. 𝟖𝟎 𝜇
= 0.10 𝜇
= 0.30 𝜇
= 0.50 𝜇
= 0.10 𝜇
= 0.30 𝜇
= 0.50 𝜇
= 0.10 𝜇
= 0.30 𝜇
= 0.50 𝜇
= 0.10 𝜇
= 0.30 𝜇
= 0.50 𝑲𝑷= 𝟎. 𝟕𝟓
𝑲𝑰= 𝟎. 𝟎𝟓 𝑲𝑷= 𝟏. 𝟎 𝑲𝑰= 𝟎. 𝟎𝟓 𝑲𝑷= 𝟏. 𝟐𝟎 𝑲𝑰= 𝟎. 𝟎𝟓 𝑲𝑷= 𝟎. 𝟕𝟓
𝑲𝑰
= 𝟎. 𝟎𝟕𝟓 𝑲𝑷= 𝟐. 𝟎 𝑲𝑰= 𝟎. 𝟎𝟏 𝑲𝑷= 𝟏. 𝟎 𝑲𝑰= 𝟎. 𝟏𝟓 𝑲𝑷= 𝟑. 𝟎 𝑲𝑰= 𝟎. 𝟏𝟎 𝑲𝑷= 𝟓. 𝟎 𝑲𝑰= 𝟎. 𝟎𝟓
15.5𝑛2+ 3.5𝑛 4𝑛2+ 4𝑛 2.5𝑛2+ 2.5𝑛
3𝑛2+ 2𝑛 3𝑛2+ 2𝑛 + 1
ℝ𝑛→ 𝑛
∈→
𝜏̅ →
𝑡 ∈ [−𝜏̅, 0] → −𝜏̅ ≤ 𝑡 ≤ 0, 𝑡& − 𝜏̅ > 0:
𝑋𝑇→ 𝛼 & 𝛽 → 𝜇 →