![Page 1: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/1.jpg)
Flexible AC Transmission System Overview
![Page 2: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/2.jpg)
Flexible AC Transmission System
Alternating current transmission systems incorporating power electronics-based and other static controllers to enhance controllability and increase power transfer capability
![Page 3: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/3.jpg)
Constraints on Useable Transmission Capacity
• Dynamic:– Transient and dynamic stability– Subsynchronous oscillations– Dynamic overvoltages and undervoltages– Voltage collapse– Frequency collapse
![Page 4: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/4.jpg)
• Steady-State:– Uneven power flow– Excess reactive power flows– Voltage capability– Thermal capability
![Page 5: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/5.jpg)
FACTS Controllers
• Static VAR Compensator - SVC• Thyristor Controlled Series Compensator - TCSC• Thyristor Controlled Phase Angle Regulator - TCPAR• Static Synchronous Compensator - StatCom• Solid State Series Compensator - SSSC• Unified Power Flow Controller - UPFC
![Page 6: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/6.jpg)
US FACTS Installations
San Diego G&E/STATCOM/100 MVA
Mitsubishi
Eagle Pass (Texas)Back-to-back HVDC
37 MVA/ ABB
CSWS (Texas)STATCOM/ 150
MVA / W-Siemens
Austin EnergySTATCOM/ 100MVA
ABB
AEP/ Unified Power Flow Controller /100 MVA/ EPRI
TVASTATCOM/ 100MVA
EPRI
Northeast Utilities/ STATCOM/ 150 MVA/
Areva (Alstom)
NYPA/ Convertible Static Compensator/
200 MVA
Vermont Electric/ STATCOM/ 130
MVA/ Mitsubishi
![Page 7: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/7.jpg)
• Power transfer between areas can be affected by adjusting the net series impedance.
• Transmission line capability can be increased by installing a series capacitor which reduces the net series impedance.
Power Flow ControlPower Flow Control
![Page 8: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/8.jpg)
UPFC
![Page 9: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/9.jpg)
UPFC
• may control voltage, impedance, and angle• impacts active and reactive power flow in line
![Page 10: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/10.jpg)
Basic OperationBasic Operation
![Page 11: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/11.jpg)
UPFC CapabilitiesUPFC Capabilities
• Increase transmission line capacity
• Direct power flow along selected lines
• Powerful system oscillation damping
• Voltage support and regulation
• Control of active and reactive power flow at both sending- and receiving-end
![Page 12: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/12.jpg)
OperationOperation
• Reactive power is generated or absorbed by the shunt inverter to control bus voltage
• Reactive power is generated or absorbed by the series inverter to control the real and/or reactive power flow on the transmission line
![Page 13: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/13.jpg)
Cont’dCont’d
• A portion of the real power flow on the transmission line is drawn from the bus by the shunt inverter to charge the DC capacitor.
• Real power is inserted into the line through the series inverter.
![Page 14: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/14.jpg)
jXSV RV
SRP
sinS RSR
V VP
X
Power flow in a transmission line
To increase PSR, increase
and R SV V jXI
jXI
SV
RV
![Page 15: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/15.jpg)
AV BVinjV- +
AVinjV
BV
jXSV RV
SRP
RV injV- + sinS RSR
V VP
X
jXIinjV
SV
RV
![Page 16: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/16.jpg)
How is Vinj created?
V+b1
a2
a1
b2
c1
c2
![Page 17: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/17.jpg)
V+b1
a2
a1
b2
c1
c2
a1 on, b1 on, c1 offVab=0, Vbc=V, Vca = -V
a1 on, b1 off, c1 offVab=V, Vbc=0, Vca = -V
V+a1 b1 c1
c2b2a2
V+a1 b1 c1
c2b2a2
a1 on, b1 off, c1 onVab=V, Vbc=-V, Vca = 0
![Page 18: Flexible AC Transmission System Overview. Flexible AC Transmission System Alternating current transmission systems incorporating power electronics-based](https://reader035.vdocuments.mx/reader035/viewer/2022062221/56649dc35503460f94ab5ad0/html5/thumbnails/18.jpg)
Sine-triangle PWM
0 100 200 300 400 500 600 700-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
0 100 200 300 400 500 600 700
0
0.5
1
Va
0 100 200 300 400 500 600 700
0
0.5
1
Vb
0 100 200 300 400 500 600 700-1
0
1
Vab