Introduction
There existed three met hods for fault location : impedance method, fault analysis method and t raveling wavemet hod . The fir st two met hods have low precisions for influence of t hese cases : line parameter s ,fault point grounding impedance , operating mode of power system. The t raveling wave met hod has a higher precision , so it has been widely used now.There’re two met hods according to different t raveling waves data : single terminal location methodand two terminal location met hod . Two terminal t raveling waves location method is employed in this paper .
The location p recision of t raveling wave method is influenced by wave velocity , line lengt h and the arriving time of wave f ront . How to accurately acquire t he arriving time of wave f ront is very important , and al so difficult . There are t hree
main algorit hms to achieve t his goal ; these are differential coefficient method , wavelet analysis met hod and correlation analysis met hod. It is easy to get the arriving time of wave f ront by t he moment when the differential coefficient of wave signal is beyond a given threshold , but t his algorit hm has a low p recision and may be influenced by noises . The classical wavelet analysis algorit hm has a higher precision in most cases . Modulus maxima principle is used to get t he mutation point in t his algorit hm . Now t his algorit hm is used widely , but t his met hod is so sensitive to the signal’s mutation point , it’s precision may be influenced.The correlation analysis algorithm is int roduced in t his paper to avoid above mentioned difficulty.The principle and t he met hod of how to use correlation analysis algorithm to locate t he fault in transmission line are int roduced. Some simulation modules are const ructed and some analysis results are given in t his paper .
