The Course Completion Work I in question analyzes the efficiency of the Negative Sequence
Voltage (NSV), applied to the detection and distinction of the conductor break compared to
other disturbances, which commonly occur in the distribution system, and other system events,
such as capacitor bank switching, distributed load switching, concentrated load switching and
side branch switching. The applied methodology is simple and practical to be implemented in
distribution systems, in addition to aiming at reducing the costs of implementing and
maintaining measuring devices used in the distribution system. So far, the distribution system
used for the tests was the 5-bus, 33-bus, 34 bus buses from the IEEE, which in order to validate
the performance of the method, tests were performed with the computer simulation program
ATPDrawTM, in order to extract characteristics from the signs of tension. Subsequently, using
Octave software, a white Gaussian noise was added to the three-phase signals and the method
is considered immune to noise. Then, the signal was filtered through a second order Butterworth
filter with a cutoff frequency of 180 Hz. Subsequently, the filtered three-phase voltages Va, Vb
and Vc were windowed at each cycle (γ), with a sampling rate of 128 samples per cycle. Then,
the phasors were calculated using the fast Fourier transform. Finally, in order to achieve the
least number of measurement devices to be implemented and thus reduce the operating costs of
the system, the system was implemented in the GAMS software which provided an optimization
of the best voltage measurement points in the system. The results demonstrate that the detection
of conductor rupture through the NSV occurred efficiently, distinguishing it from the other
events in the system, therefore, showing an efficient, robust, precise and reliable methodology
to aid in the correction of disturbances in the system. electrical system, providing greater
reliability and quality of electricity distribution. The work will continue through the application
of the same methodology to other distribution systems with different topologies and
characteristics, in order to validate the proposed method.
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