15-03-2010, 05:28 PM
Introduction
This article reviews the application of Flexible AC Transmission System (FACTS) concepts to the improvement of Power System utilisation and performance. It summarises literature on using high speed thyristor based control of HVAC power system elements to enhance the power carrying capacity of existing transmission circuits without compromising reliability. the issues addressed are transient and dynamic stability, power flow control, reactive support and voltage stability. It is concluded that FACTS devices have the potential to significantly increase system stability margins thereby increasing loading capability of existing transmission corridors. FACTS devices are attractive when compared with the other methods considering the economic aspect.
The FACTS Technology
The term FACTS describes a wide range of controllers, many of which incorporate large power
electronic converters, that can increase the flexibility of power systems making them more
controllable. Some of these are already well established while some are still in the research or
development stage.
the following technological attributes are possessed by all FACTS devices:
-Provide dynamic reactive power support and voltage control.
-Improve system stability.
-Reduce the need for construction of new transmission lines, capacitors, reactors, etc
which reduce the environmental and regulatory concerns and also Improve aesthetics by reducing the need for construction of new facilities such as
transmission lines.
-Mitigate potential Sub-Synchronous Resonance problems.
-Control real and reactive power flow.
To determine which FACTS device would be the most beneficial, the following devices were examined:
Thyristor Controlled Series Capacitor (TCSC):TCSC provides dynamic control of the series compensated lines, which could increase
transfer capability
Static Condenser (STATCON):a STATCON mainly provides dynamic reactive power but does not directly control the flow of real power on a transmission line it was not considered.
Thyristor Controlled Phase Angle regulator (TCPAR):A TCPAR, is equivalent to a mechanically phase shifting transformer but unlike a UPFC it does
not provide controlled reactive power generation
Unified Power Flow Controller (UPFC):
A TCPAR, is equivalent to a mechanically phase shifting transformer but unlike a UPFC it does not provide controlled reactive power generation.
High-Voltage DC Transmission and Static Var Compensators are examples of power electronic
systems (i.e. FACTS devices) that are already well established.The initial development
techniques for many power electronic devices have been proven in numbers of variable speed
motor drive installations. Presently these techniques are being applied to equipment having
higher power ratings; i.e., capable of being installed within utility transmission and distribution
systems.
for details:
http://informaworldsmpp/content~db=all~content=a778208614
[attachment=2646]
This article reviews the application of Flexible AC Transmission System (FACTS) concepts to the improvement of Power System utilisation and performance. It summarises literature on using high speed thyristor based control of HVAC power system elements to enhance the power carrying capacity of existing transmission circuits without compromising reliability. the issues addressed are transient and dynamic stability, power flow control, reactive support and voltage stability. It is concluded that FACTS devices have the potential to significantly increase system stability margins thereby increasing loading capability of existing transmission corridors. FACTS devices are attractive when compared with the other methods considering the economic aspect.
The FACTS Technology
The term FACTS describes a wide range of controllers, many of which incorporate large power
electronic converters, that can increase the flexibility of power systems making them more
controllable. Some of these are already well established while some are still in the research or
development stage.
the following technological attributes are possessed by all FACTS devices:
-Provide dynamic reactive power support and voltage control.
-Improve system stability.
-Reduce the need for construction of new transmission lines, capacitors, reactors, etc
which reduce the environmental and regulatory concerns and also Improve aesthetics by reducing the need for construction of new facilities such as
transmission lines.
-Mitigate potential Sub-Synchronous Resonance problems.
-Control real and reactive power flow.
To determine which FACTS device would be the most beneficial, the following devices were examined:
Thyristor Controlled Series Capacitor (TCSC):TCSC provides dynamic control of the series compensated lines, which could increase
transfer capability
Static Condenser (STATCON):a STATCON mainly provides dynamic reactive power but does not directly control the flow of real power on a transmission line it was not considered.
Thyristor Controlled Phase Angle regulator (TCPAR):A TCPAR, is equivalent to a mechanically phase shifting transformer but unlike a UPFC it does
not provide controlled reactive power generation
Unified Power Flow Controller (UPFC):
A TCPAR, is equivalent to a mechanically phase shifting transformer but unlike a UPFC it does not provide controlled reactive power generation.
High-Voltage DC Transmission and Static Var Compensators are examples of power electronic
systems (i.e. FACTS devices) that are already well established.The initial development
techniques for many power electronic devices have been proven in numbers of variable speed
motor drive installations. Presently these techniques are being applied to equipment having
higher power ratings; i.e., capable of being installed within utility transmission and distribution
systems.
for details:
http://informaworldsmpp/content~db=all~content=a778208614
[attachment=2646]