31-05-2012, 01:59 PM
Flexible AC Transmission System Overview
Flexible AC Transmission System Overview.ppt (Size: 973 KB / Downloads: 111)
Alternating current transmission systems incorporating power electronics-based and other static controllers to enhance controllability and increase power transfer capability
Constraints on Useable Transmission Capacity
Dynamic:
Transient and dynamic stability
Subsynchronous oscillations
Dynamic overvoltages and undervoltages
Voltage collapse
Frequency collapse
Steady-State:
Uneven power flow
Excess reactive power flows
Voltage capability
Thermal capability
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
Power Flow Control
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.
UPFC 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