| Summary: | Silicon carbide (SiC) and metal oxide (ZnO) arrester are protection
equipment of high voltage system against overvoltage due to lightning. Lightning
produces more electric charge in some electric power line. Lightning surge which
flow through long electric power line can modify lightning waveform, one of
which is the change in the value of front time. Therefore, it is important to know
the effect of front time to the arresters residual voltage of two different kind of
arresters.
The research was conducted through laboratory-scale testing using major
equipment such as high voltage generator, impulse voltage generator, and
oscilloscope. Modified value of the inductor in impulse voltage generator circuit
produce different value of the front time of lightning (< 45μs). Then input voltage
having different value of front time were applied to both arresters. We must vary
input voltage to get comparable amplitude of impulse voltage (60 kV and 100
kV).
According to the test, it is known that variation of front time gave effect
to both arrester, SiC and ZnO. In SiC arrester, the higher value of the front time
resulted in a decrease in the value of residual voltage. The average value of
residual voltage was 33.51 kV for 60 kV input voltage and 39.91 kV for 100 kV
input voltage. In ZnO arrester, the higher value of front time resulted in a decrease
in the value of residual voltage until reaching the peak time of 17 microseconds.
The average value of ZnO arrester residual voltage was 39.97 kV for 60 kV input
voltage and the 42.15 kV for 100 kV input voltage. The entire test result indicated
SiC arrester residual voltage value lower than ZnO arrester.
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