Study On Data Acquisition And Analysis Of Insulator Leakage Current Online Monitoring System Of Overhead Line

Existing insulator leakage current online monitoring system has sorts of problemssuch as inconvenience of mounting, absence on analysis ways of leakage current anddifficulty of diagnosis of pollution condition on insulator surface. In this paper, the keytechnologies of insulator leakage current online monitoring system are researched and anew type of leakage current acquisition and analysis system is developed.Non-contact leakage current sensor is adopted in this system and provides amounting way without change original insulator-tower structure. Application of newersensor adapter circuit lead to improvement of performance and solution of deficiency inlow precision, narrow band and sensitivity of change in magnetic core parameter oftraditional rogowski coil based current sensor.USB interface based data acquisition unit with high sample rate is developed, as aresult, the detailed leakage current waveform is observable therefore the detailedanalysis of leakage current and even the diagnosis of pollution condition on insulatorsurface is probable. At that time, the opening interface with 8 channels for staticparameter sensor is provided and environment parameter sensor or the other staticparameter sensor can be attached for specified requirement. System software canreal-time observe leakage current waveform and static parameter with 8 channels and alldata can be stored for post observation and analysis.Modern power spectral estimation is applied in leakage current analysis in thispaper and the global character of leakage current is obtained by associated analysis ofpower spectral character and root mean square value of leakage current.Detailed structural information of leakage current signal is acquired by way ofsyntactical pattern recognition and therefore leads to the profound grasp of dischargefeatures on insulator surface.This system is applied for manually polluted insulator measuring in laboratory andis proved to be stable and dependable. Analyzing by analysis module in system softwareof leakage current result in distinct identification in analyzing space of pollutiondischarge on insulator surface.As a conclusion, this system is an integrated system of insulator leakage currentmonitoring and pollution discharge analysis with efficient analysis method of pollutiondischarge. Progress in both of current sensor and analysis way of pollution discharge isachieved.