The Analysis Of Cable Partial Discharge Signals Detection And Location Based On Ultrasonic

With the development of economy,power cables play an important role in power transmission,and the reliability of operation is of great significance to the safe operation of the whole power system.Partial discharge is one of the important reasons leading to insulation damage and cable damage.Judging the characteristics of partial discharge and locating the fault point is of great significance for the early detection of the early fault of cable.As the cable discharge will produce ultrasonic signals,cable partial discharge ultrasonic detection system is designed in this paper to study the ultrasonic signal,using a method which combine software and hardware to locate the discharge of the cable and analyze the discharge signal.The main work of the paper is as follows:1)The cable partial discharge ultrasonic detection system is designed,deal with the ultrasonic signal by the amplifier circuit and filter circuit.Collecting date by the data acquisition card and transferring to the computer.2)Writing a filter program by the Labview programming language and filtering the signal on the computer,at the last,achieved the purpose of filtering.3)Conducting wavelet analysis by the Matlab programming language,decomposing and composing the signal and removing the white noise.In the last,analyzing the spread and decay law of ultrasonic.4)Using the system conducted a number of experiments to locate the discharge point in the air and soil and the calculation error within the allowable range.By analyzing multiple sets of experimental data,result explained that can realize the function of partial signal detection and location by this system.