Research On The Electric Characteristics Of The Single Insulator And Insulator Strings

The reliable and safe operation of the electrical equipment in power system depends on the insulation level of the equipment and the voltage set on the insulation. With the rapid development of the national economy, the rising of the electrical system voltage caused by the increasing of the electricity consumption and the lengthening of the transmission distance made the problem of the electrical equipment insulation more and more serious. This article focused on the study and research of the online detection of the insulator.Based on the large searches of the domestic and the overseas references and researching results, and integrating the latest production in computer and micro electronics, a new design, which has a better ratio in performance-price, was used to examine the deteriorated status on-line. It is based on to monitor the corona pulse current caused by the applied voltage on the insulator strings. A lot of experiments and the detailed analysis proved that the corona discharge phenomena conforms with the statistic rules and to monitor the corona current is a effective method to find the early insulation faults. After a series of theoretical analysis and computation to the experimental results with the help of statistical hypothesis and verification method. The experimental results of the insulator strings about the voltage distribution and leakage current at high voltage transmission lines show that the voltage distributions have some randomicity, though it is in horseshoe taking one with another. The voltage suffered by every single insulator and the whole leakage current are different with the difference of the deteriorated degree and the position and the quantities of the fault insulator when there are some fault insulators in the transmission line.In order to realize the survey of the deteriorated insulators on-line, special designed corona current transducer and leakage current transducer were developed according to the spectrum characteristics of corona current from the experimental results. Its main characters are the simples in manipulation, the convenient when outing and the clearness of its display.