The document discusses Flexible AC Transmission Systems (FACTS) which use power electronics-based equipment to control parameters on power grids like impedance, current, and voltage. It describes different types of FACTS controllers including series controllers that inject voltage, shunt controllers that inject current, and combined series-series and series-shunt controllers. It provides details on STATCOMs which control reactive power injection through a voltage source converter and UPFCs which are a combination controller. Finally, it lists advantages of FACTS like improved voltage control, stability, reduced losses, and increased transmission capacity.
3. What is FACTS?
The FACTS technology is a collection of controllers,
which can be applied individually or in coordination
with others to control one or more of the interrelated
system parameters, such as series impedance, shunt
impedance, current, voltage, and damping of
oscillations.
5. Series controller
>The series controller could be a variable impedance or a
variable source both are power electronics based. In principle,
all series controllers inject voltage in series with the line.
Shunt controller
>The shunt controllers may be variable impedance connected
to the line voltage causes a variable current flow hence
represents injection of current into the line.
6. Combined series-series controllers:
The combination could be separate series
controllers or unified series-series
controller--- Interline Power Flow Controller.
Combined series-shunt controllers:
The combination could be separated series
and shunt controllers or a unified power flow
controller
7.
8. STATCOM-Static Synchronous Compensator
>A synchronous compensator=synchronous machine
>operation=by controlling the field current of the synchronous machine
Any amount of positive or negative reactive power can be injected into
the system
>Consists –battery and voltage source converter connected in Parallel
through a transformer
>control-through firing angle of GTO’s
>advantage-response is very fast & has symmetric lead-lag capability
13. ADVANTAGES OF FACTS:
>Dynamic voltage control
>increase in transient stability limit
>Reduction in power loss
>improvement in voltage profile
>increase in power transfer capability
