1) The document discusses improvements to voltage regulation systems at electricity plants in Thailand from 2554 to 2555. 2) A new Automatic Line Voltage Controller (ALVC) was installed to work alongside the existing Automatic Voltage Regulator (AVR) systems to better maintain voltages within allowed ranges. 3) Over this period three kaizen or continuous improvement projects were conducted to refine the performance of the ALVC system - improving its reactive power control, PID function, and resolving issues with power supply and I/O configuration.

1. (Electricity Generating Authority of Thailand)
PA-PLUS
“ ”
“Positive Attitude” ”
AGS2614/0311-22/0712-2-KT
17 2554
Automation Kaizen
19 2555
9
7
“ 230 kV ”

2. 53 2
PA-PLUS

3. PA-PLUS
PA-PLUS
QCC
KAIZEN
1 35 12 6
2 31 5 5
3 29 4 4
4 28 3 2
5 27 3 1
6 27 2 1
7 27 2 1
-
29
4
– .

4. PA-PLUS
. (Planned Outage
Maintenance) (Unplanned Outage / Breakdown
Maintenance)
Automatic Voltage Regulator (AVR)
(Generator Voltage)
(Generator)
Static Frequency Converter (SFC)
Startup Gas Turbine
SFC
Start
On Load Tap Changer (OLTC)
Tap
(Service Station
Transformer)
Automatic Synchronizer (ASS)
PA-PLUS

5. Active Power
Reactive Power
Capacitor Bank
Static VAR Compensator
Capacitor Bank
Micro Controller
Programmable Logic Control (PLC)
Distributed Control System (DCS)

6. ?
220 10% volt
220 volt
230 220
230 kV
13.8 kV
220 V
10 %
kV V

7. Active Power
Active Power
Active Power + Reactive Power

8. (Generator)
/
Automatic Voltage Regulator (AVR)
Capacitor Bank
Capacitor Bank
Capacitor Bank
Static VAR
compensator
Static VAR Compensator
Static VAR
Compensator
G AVR

10. .
:
(NCC*) . 2554NCC 2%
(100%)
* NCC National Control Center :
1
.

11. 230 kV
230 kV
13.8 kV
220 V
220 volt
kV
220
10 %
.
2 %
230
V
230 kV 220 volt 5% .
(Voltage Quality)
220 volt 2%

12. 
 230 kV
230 kV
220 volt 2%
“ 230 kV ”
KAIZEN

13. - (Voltage Quality)
- (Ethic)
- (Morale)
-
-
- 220 2% volt ( Voltage Quality)
-

14. NCC
Control Room
AVR
NCC
230 kV
220 volt 2 %
Reactive Power
NCC
.....
( )
:
24
NCC

15. “ 230 kV
24 ”
24
NCC
98% 102%
-2% +2%
(100%)
manual
105 %
* 100% 230 kV
(Load)
(KV)
105 %
Load (MW)
7 – 10
kV (%)

16. WHAT WHAT TO DO WHERE 2554 2555 - WHO HOW
11 12 01 02 03 04 05 06 07 08 09-
P
-
-
-
-
, -
-
-
PDCA.
- -
- -
D (
)
-
C /
-
-
A
-
-
-
-
-
1-2
1 2,3 4,5 6 7 8 9
9 90 %
Plan
Actual

17. NCC
Control Room
NCC
AVR
.....
Kaizen 1
?
NCC
NCC
230 kV
220 volt 2 %

18. 3
Micro Controller
8 2
2. Distributed Control System (DCS) 16 3
Programmable Logic Controller (PLC)
48
1 1 5,000,001 1 2
2 2 1,000,001 - 5,000,000 2 1 2
3 3 100,001 - 1,000,000 3 6 1
4 4 0 - 100,000 4 6
•
  
 
   1
Kaizen 1

19. *
Automatic Line
Voltage Controller
(ALVC)
:
PLC Lab
(PA-PLUS)
(PA-PLUS)
PLC
( )
(PA-PLUS)

20. ALVC AVR
NCC
ALVC
NCC
+
NCC Computer
NCC
-
+
ALVC*
AVR
.....
NCC
230 kV
220
volt 2%

21. Automatic Line Voltage Controller
Planned Outage
Local Control Panel
Operator
NCC
PLCLine Voltage
Power Transducer
Industrial Ethernet
PLC
AVR
Automatic Line Voltage Controller (ALVC)

22. Automatic Line Voltage Controller
NCC
14 . . 55 ALVC
3
18 . . 55 ALVC
25 . . 55 ALVC

23. Automatic Line Voltage Controller
4 5
KAIZEN 1
Automatic Line Voltage Controller
-10
10
30
50
70
1
MVAR
Time
Reactive Power
220
225
230
235
240
1
kV
Time
Bus Voltage
Actual
Setpoint
KAIZEN
ALVC Reactive Power

24. • WHY WHY Analysis
1
ALVC
Reactive Power
ALVC*
Reactive Power
PID**
PLC
output PLC
OMRON
output
2
Reactive Power
1
Power Transducer
Reactive
Power
* ALVC Automatic Line Voltage Controller
(Kaizen 2)
** PID Function
Output

25. 1 Reactive Power :
Static test Power Transducer
• AVLC Reactive Power
Power Transducer Output Test
(Kaizen 2)
0
1
2
3
4
5
6
0 0.5 1 1.5
PowerTransducerOutput(V)
ReactivePower (P.U.)
Reactive Power
(Leading -)
Reactive Power
Lagging (+)

26. 2 PID PLC OMRON Output :
PID Output
• AVLC Reactive Power
PID(190)
Setpoint
feedback
max
min
PID Output
Max, Min
(Kaizen 2)
** PID Function Output

27. (Kaizen 2)
PID OMRON Max , Min Limit
PLC PID Output

28. (Kaizen 2)
KAIZEN 2
Automatic Line Voltage Controller
6 5
230
231
232
233
234
235
236
237
238
239
240
1
kV
Time
Bus Voltage
Actual
Setpoint
-25
-20
-15
-10
-5
0
Reactive Power
GEN1
GEN2
GEN3
Automatic Line Voltage Controller KAIZEN 2
Time
MVAR

29. (Kaizen 2)
Automatic Line Voltage Controller
5
25 5
KAIZEN 2
Automatic Line Voltage Controller KAIZEN 2
Set Point
Actual Bus Voltage
Bus Voltage 230 KV Set point

30. . OFF Power Supply ALVC On
12 2555
ALVC Bus 230 kV
Alarm “I/O
Configuration
Error” PLC
KAIZEN 3
( 2)
Analog Input Modules

31. • WHY WHY Analysis
1
Hardware PLC
Analog Input
PLC
2
Battery
Back Up
1
Off Power
Supply
* ALVC Automatic Line Voltage Controller
Software PLC
Kaizen 3

32. 1 Battery PLC I/O
Configuration Power OFF
:
Battery 3.58 Volt Spec. 3.6 Volt
•
Kaizen 3

33. 2 PLC :
Default I/O Configuration Program Analog Input
Kaizen 3
Ch.8 BUS
0-10 Volt Default 10Volt)
I/O Table
•

34. PLC Default I/O Configuration
“ON, OFF” Power Supply ALVC
Disable Function
(Kaizen 3)
I/O Table Setting

35. KAIZEN 3
OFF
Power Supply 6 . 6
( 3)
ALVC BUS Voltage

36. KAIZEN
KAIZEN
KAIZEN 1 ALVC
Reactive Power
KAIZEN 2
Function Block (PID) ALVC
KAIZEN 3
Analog Input Default OFF Power Supply PLC
Logic setting Analog Input
KAIZEN 230 kV NCC 24

37. 1.
ALVC
2. ALVC

38. :
Design
Site Installation
Static Function Test
Factory Test
Commissioning Test
Loop Wiring Test
 Interface ALVC

 Run Simulator Mode
 Site
 Interface
 Function

Parameter

39. : 230 kV 220 volt 2%
Command from NCC
Synchronizing
Enable ALVC Mode
Start up unit
Set voltage setpoint
Select unit
 Start up unit

 unit
 ALVC

 HMI

40. 230 kV 24
 :
 :
-
(Voltage Quality)
- (Ethic)
-
-
-
- 220 2% volt ( Voltage Quality)
-

41. Automatic Line Voltage Controller

42. 3-4
1-2

43. EGAT-AVR Redundant
1.
EGAT-AVR
2.
3.EGAT AVR
2554