Research On Experimental System Of Catenary Insulator State In The Sand Area

The state of catenary insulator is related to the catenary can work normally. The westernof our country is almost sand area, research on the effects of typical environment of dust areafor the state of catenary insulator is important for the safety of train running on time. A sandarea catenary insulator state test system is built in laboratory. The overall structure of thesystem is designed. Take catenary insulator of sand area as the research object to research theproblem of insulator state detection. Leakage current of catenary insulator and environmentalparameters are used to characterize the insulator work status.In terms of hardware, artificial climate chamber is built to simulate the typical environ-ment of sand area, according to the national standard for the safe distance of high-voltagecharged body distribution equipment requirements, the artificial climate chamber dimensionsare calculated. Considering the factors of price and performance, the temperature humidityand wind speed sensor are selected, the production of artificial climate chamber is completed.According to the characteristics of leakage current of catenary insulator, the appropriateleakage current sensor is selected, and then, the conditioning circuit with overvoltageprotection function is designed and implemented. Combining with the conditioning circuitoutput, the proper parameter data acquisition card is selected. Since the state test system isoperated at the environment with high voltage and strong magnetic field, the hardwareanti-interference measures have been taken from the three aspects: interference source,coupling path and receiver. The test results show that the artificial climate chamber cansimulate the dust environment, the output voltage which after the signal conditioning circuit issuitable for direct data acquisition card collection.In terms of software, the measurement system with the modules of data acquisition, datastorage and data playback is designed based on laboratory virtual instrument engineeringworkbench(LabVIEW). Implemented in LabVIEW environment of continuous high speed andlarge capacity data acquisition card collection, the functions of display, storage and playbackof test data are accomplished. To get a more accurate signal leakage current, the method thatcombining improved empirical mode decomposition and wavelet threshold method is taken todenoise the collected leakage current of catenary insulator. The measurement system andoscilloscope are used to collect the testing voltage signal which analog signal generatorgenerates, results indicate that the measurement system has a high precision, with continuousstorage and playback functions which oscilloscope does not have. By measuring leakagecurrent of catenary insulator which is tested in the process of artificial climate chamber, theresult shows that the measurement system can measure changes of leakage current and localarc of catenary insulator, and the method that combining improved empirical mode decomposition and wavelet threshold method can denoise the collected leakage current signalof catenary insulator effectively which is good for the prediction of insulator state of catenaryin sand area.