APPARATUS OF FREQUENCY ANALYSIS FOR PARTIAL DISCHARGE OF GAS INSULATED SWITCHGEAR

摘要

A frequency analysis apparatus for detecting partial discharge of a gas insulated switchgear is provided to reduce an area by reducing the number of filters and to improve noise figure by decreasing damping of the signal flow. A frequency analysis apparatus detects the abnormal state of a gas insulated switchgear by receiving a partial discharge signal from a sensor installed in the gas insulated switchgear. A switching unit(30) comprises anti-parallel diodes preventing breakage generated by high voltage and high load, in receiving a partial discharge sensor signal of 0.5-1.5GHz from the sensor and a digital signal control unit. In the digital signal control unit, a buffer buffers the sensor signal and provides the buffered sensor signal. A digital controller receives a signal output from the buffer and transmits the sensor signal to a digital signal conversion unit at the intervals of sweep time by using a 4-bit control signal if a partial discharge signal is detected, and informs the position of the sensor. And, the digital controller transmits the sensor signal to a spectrum analyzer. The spectrum analyzer(32) analyzes the sensor signal supplied from the switching unit. The digital signal conversion unit converts the RF(Radio Frequency) type sensor signal supplied from the switching unit, into a digital signal.