05-09-2012, 11:06 AM
DISTRIBUTION STATIC COMPENSATOR (DSTATCOM)
DSTATCOM.pptx (Size: 492.04 KB / Downloads: 43)
STATCOM
STATCOM is a regulating device used on ac electricity transmission network. It is based on power electronics voltage source inverter and can act as either a source or sink of reactive ac power to electricity network.
If connected to a source of power. It can also provide active ac power. It is member of the FACTS family.
STATCOM is installed to support electricity networks that have a poor power factor and often poor voltage regulation.
Its most common use is for voltage stability.
It is a device connected in derivation, basically composed of a coupling transformer, that serves of link between the electrical power system (EPS) and the voltage synchronous controller (VSC), that generates the voltage wave comparing it to the one of the electric system to realize the exchange of reactive power.
In its most general way, the STATCOM can be modeled as a regulated voltage source Vi connected to a voltage bar Vs through a transformer.
STATCOM - A VSC interfaced in shunt to a transmission line
The static compensator (STATCOM) uses a VSC interfaced in shunt to a transmission line. In most cases the DC voltage support for the VSC will be provided by the DC capacitor of relatively small energy storage capability. Hence, in steady state operation, active power exchanged with the line has to be maintained at zero, as shown symbolically in the Figure.
By using the transformer impedance and the angle difference between Vi and Vs , we can defined P and Q.
The angle between the Vs and Vi in the system is d. When the STATCOM operates with d=0 we can see how the active power send to the system device becomes zero while the reactive power will mainly depend on the voltage module. This operation condition means that the current that goes through the transformer must have a +/-90º phase difference to Vs. In other words, if Vi is bigger than Vs, the reactive will be send to the STATCOM of the system (capacitive operation), originating a current flow in this direction. In the contrary case, the reactive will be absorbed from the system through the STATCOM (inductive operation) and the current will flow in the opposite direction. Finally if the modules of Vs and Vi are equal, there won´t be nor current nor reactive flow in the system.
Thus, we can say that in a stationary state Q only depends on the module difference between Vs and Vi voltages. The amount of the reactive power is proportional to the voltage difference between Vs and Vi.
DSTATCOM.pptx (Size: 492.04 KB / Downloads: 43)
STATCOM
STATCOM is a regulating device used on ac electricity transmission network. It is based on power electronics voltage source inverter and can act as either a source or sink of reactive ac power to electricity network.
If connected to a source of power. It can also provide active ac power. It is member of the FACTS family.
STATCOM is installed to support electricity networks that have a poor power factor and often poor voltage regulation.
Its most common use is for voltage stability.
It is a device connected in derivation, basically composed of a coupling transformer, that serves of link between the electrical power system (EPS) and the voltage synchronous controller (VSC), that generates the voltage wave comparing it to the one of the electric system to realize the exchange of reactive power.
In its most general way, the STATCOM can be modeled as a regulated voltage source Vi connected to a voltage bar Vs through a transformer.
STATCOM - A VSC interfaced in shunt to a transmission line
The static compensator (STATCOM) uses a VSC interfaced in shunt to a transmission line. In most cases the DC voltage support for the VSC will be provided by the DC capacitor of relatively small energy storage capability. Hence, in steady state operation, active power exchanged with the line has to be maintained at zero, as shown symbolically in the Figure.
By using the transformer impedance and the angle difference between Vi and Vs , we can defined P and Q.
The angle between the Vs and Vi in the system is d. When the STATCOM operates with d=0 we can see how the active power send to the system device becomes zero while the reactive power will mainly depend on the voltage module. This operation condition means that the current that goes through the transformer must have a +/-90º phase difference to Vs. In other words, if Vi is bigger than Vs, the reactive will be send to the STATCOM of the system (capacitive operation), originating a current flow in this direction. In the contrary case, the reactive will be absorbed from the system through the STATCOM (inductive operation) and the current will flow in the opposite direction. Finally if the modules of Vs and Vi are equal, there won´t be nor current nor reactive flow in the system.
Thus, we can say that in a stationary state Q only depends on the module difference between Vs and Vi voltages. The amount of the reactive power is proportional to the voltage difference between Vs and Vi.