30-12-2010, 03:45 PM
BY
ANJANA.K.K
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CONTENTS
Introduction
Why fractional frequency?
Principle
Structure of FFTS
Application
Conclusion
References
INTRODUCTION
HVDC system
FACT( flexible AC transmission system)
Fractional frequency transmission
WHY FRACTIONAL FREQUENCY?
Better voltage regulation
Improved capacity
Lesser voltage fluctuations
Improved stability
WHY FRACTIONAL FREQUENCY?
Better voltage regulation
Improved capacity
Lesser voltage fluctuation
Improved stability
PRINCIPLE
Factors limiting transmission capacity
1) Thermal limit
2) Stability limit
3) Voltage drop limit
Stability limit
Voltage drop limit
APPLICATIONS
FFTS is particularly applicable for transmitting electricity generated by renewable energy sources
-Integrating wind farms via FFTS
ADVANTAGES
The investment in transmission system can be reduced
Wind power generator will be simplified
Gear ratio can be reduced
Number of poles can be reduced
Replacing converter of each variable speed wind generator by the cycloconverters of FFTS
More wind energy can be trapped
The voltage fluctuation induced by the wind power will reduced
CONCLUSION
It is an efficient approach to overcome inherent difficulties of conventional system:
Voltage regulation
Stability
Voltage fluctuation etc.
By the use of FFTS we can increase transmission capacity (3 times)
The operating performance will be improved
The economic profit will also increase