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Fractional
Frequency Transmission System |
The
fractional frequency transmission system (FFTS) is a very promising long-distance
transmission approach, which uses lower frequency (50/3 Hz) to reduce the electrical
length of the ac power line, and thus, its transmission capacity can be in creased
several fold. This paper introduces the experimental installation of FFTS and
primary experiment results. The experiment uses the phase-controlled cycloconverter
as the frequency changer, stepping up 50/3 Hz electricity to 50 Hz electricity
and supplying it to the utility grid. Thus, a new flexible ac transmission system
device is successfully established in this experiment. The s\nchro-nizing process
of 50/3 Hz transmission system with 50 Hz utility system is introduced in this
paper. The experiment results show that a 1200 km/500 kV transmission line can
transmit more than 2000 M\V electric power when employing the FFTS. The experiment
also illustrates that there is no essential difficulty to realize FFTS in engineering
practice NCREASING transmission distance and capacity is always the motivation
to advance power industry technologic | 1 |. In the history of the ac transmission
system, increasing distance and capacity mainly depends on raising voltage le\el
ol transmission lines. At present, the highest voltage level of the <K power
transmission line in operation is 750 kV. To further upgrade, the voltage level
encounters difficulties of material and environment issues.The high-voltage direct
current (HVDC) transmission that has no stability limit problem once became another
approach to increasing electricity transmission capacity. <<back |