Transcript Slide 1

Technical Seminar Presentation - 2004
THYRISTOR BASED FACTS CONTROLLER
Under the guidance of
Mr.Gayadhar Panda
Presented By
Anupam Pramanik
Roll no-EE200118197
NATIONAL INSTITUTE OF SCIENCE & TECHNOLOGY
Palur Hills,Berhampur-761008,Orissa,India
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
INTRODUCTION
Rapid Growth in Electrical energy combined with demand for low cost
energy
Led to development of generation sites remotely
Electrical transmission network
Comprises of transmission network
Operate at different transmission voltages
Increasing requirement of power transmission
Increases in transmission voltages
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
CONVENTIONAL CONTROL
MECHANISM
Most of controllability exists at generating station
Automatic Generation Control
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Excitation Control
Basic function to provide dc source for field excitation
Control on excitation voltage
Controls field excitation that controls generated voltage
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Transformer Tap Changer Control
Many transformers equipped with tap changers
Control carried manually or automatically
Two types
Off load tap Changer
On load tap Changer
Phase Shifting Transformer
Combining transformer connected in series with line to voltage
transformer equipped with tap changer
Introduces phase shift in a line
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
FACTS
The FACTS is a concept based on power-electronic controllers, which enhance
the value of transmission networks by increasing the use of their capacity.
Operate very fast
Enlarge safe operating limit of a transmission system without risking
stability
Replacement of mercury-arc valves by thyristors yielded:
 Robust AC/DC converters
 Minimized conversion losses
 Yielded fast control on transmitted power
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Basic Types Of FACTS Controller
Series controllers
Shunt controllers
Combined Series-Series Controllers
Combined Series-Shunt Controllers
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Basic Types Of FACTS Devices
Static VAR Compensators
Thyristor controlled series compensators
Static Synchronous Compensator
Unified Power Flow Controller
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Advances in Power Electronics Switching
Devices
Thyristors offered controlled turn-on of currents
Most applications were based on the natural commutation of currents
In special cases forced commutation were used
The present trend is to produce high-power electronic building blocks
(HPEBBs)
To configure high-power switches and converters, thus eliminating the customdesign at the device level
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Principles and Applications
In high-power applications, semiconductor devices are used primarily as
switches.
Thus a thyristor switch offers current control in a reactor, rendering it a
controlled reactor
A thyristor switch is used only to turn on or turn off a capacitor, thereby
implementing a switched capacitor
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Parallel combination of switched capacitors and controlled reactors
provides a smooth current-control
Shunt combinations of thyristor-controlled reactors (TCRs) and
thyristor-switched capacitors (TSCs) yield static VAR compensators
(SVCs).
GTO devices makes forced commutation possible, and therefore
PWM converters offer a more elegant solution
An alternative to a thyristor-controlled SVC is a GTO-based VSC
that uses charged capacitors as the input dc source and produces a 3phase ac voltage output in synchronism and in phase with the ac
system.
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
A control on the output voltage of this converter—lower or higher
than the connecting bus voltage—controls the reactive power drawn
from or supplied to the connected bus.
The functions of an SSSC and a STATCOM, in fact, may be
combined to produce a unified power-flow controller (UPFC).
UPFC offers a fast, controllable FACTS device for the flow of
combined active–reactive power in a line.
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
CONCLUSION
Energy congestion in critical transmission corridors must be avoided
to eliminate the risk of missed business opportunities
A power-transmission company must make the best use of its
transmission capacity and ensure that transmission losses are reduced
to their lowest values
A transmission company must create the maximum safe operating
limits to allow power injection and tapping from its buses without
risking stable operation
Several recent projects have been undertaken to make greater use of
semiconductor devices for FACTS
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Presented By:- Anupam Pramanik(EE200118197)
Technical Seminar Presentation - 2004
Presented By:- Anupam Pramanik(EE200118197)