Research On The Detection Device For The Phase-Voltage Of Overhead Transmission Lines Without Grounding Line

In the power system, in order to ensure the safe and stable operation of the powersystem, it is necessary to detect the voltage, current and other parameters in real time.Along with the high speed development of the social economy of the country, the powersystem has also been a rapid development. The power grid’s voltage grade risesceaselessly. The testing equipment that supports it also has a digital and automaticdevelopment. The traditional voltage transformer can’t satisfy the demand of modernpower system in voltage grade and the detection mode.This paper analyzes the traditional detection methods and the advantages anddisadvantages of new on-line monitoring. Then, the paper describes the detecting theoryfor the voltage by the use of the spatial capacitance divider in detail. Based on the analysisof the electric field around the overhead transmission line,this paper studies thecharacteristics of the spatial capacitor between the spatial conductor and the ground.Based on this,the paper designed and processed the voltage sensor. With the use of thesignal processing circuit, the paper can take a process on the output signal of the voltagesensor to obtain the relation between the input and output.In the end, the following ADcircuit get the output signal for a further processing and analysis using. After this, thepaper take a lot of experiments with the complete set designed by the author to study thecharacteristics of the set on different conditions especially with a differet height. Theexperimental data and results prove that the device works well in the indoor environmentand the input and output keeps a linear relationship.