ISSTDR을 이용한 저압 지중 케이블의 경미한 고장 검출

SSTDR(spread spectrum time domain reflectometry) is known to have excellent performance to detect cable fault(open and short). However, if the fault type is soft fault like as partial disconnection, attenuation of the reflected signal becomes larger and hence correlation coefficient in SSTDR becomes smaller, which makes fault detection difficult. Therefore, in order to solve the problem of SSTDR, this paper uses ISSTDR(improved SSTDR) to detect the peak value of the correlation coefficient of the reference signal with time-frequency correlation analysis, and then the peak value of the correlation coefficient of the reflected signal is detected after removing the reference signal. The performance of ISSTDR was validated via an experiment in low-voltage power cables. The performance evaluation showed that the ISSTDR can track fault location.