Fault Diagnosis for High Voltage Distribution Networks Using Pseudorandom Binary Sequence and Cross Correlation Technique

In this paper, a new reflectometry scheme, using incident pseudo random binary sequence (PRBS) is investigated for the first time to diagnose fault in the radial distribution system. The PRBS disturbance is amplified by current transformer and then is injected into the line. The profile of cross correlation (CCR) of echo response with input stimuli is used to classify the fault types. Fault location is measured based on the time delay of PN sequence cross-correlated response from the autocorrelation (ACR) location. The most important feature of this method is capacity to extract fault position from multiple reflections caused by a variety of discontinuities along distribution line. A multi-branch distribution circuit is modeled by cascading some segments together. Simulink package has been known as a powerful tool to simulate the different fault conditions. The accuracy of measurement demonstrates the effectiveness and reliability of proposed algorithm.