Distribution of space charge around conductor line in a small corona cage at various influencing factors

Summary

With the increase of dc transmission voltage grade, the space charge in air is one of the most noticeable reasons affecting corona discharge, which is closely related to corona discharge mechanism, initiation, self-maintenance condition and corona loss. How to obtain the distribution of space charge under the influence of the different factors is always a problem remaining to be settled. In this paper, based on acoustic stimulation method, a charge sensing system is developed to study it. For the further research, the variation of space charge density with voltage and conductor radius is studied by using a contactless measuring device with the sensing system in laboratory. The charge sensing system consists of acoustic emission, space charge generation and signal receiving system. The sound wave from emission system stimulates the space charge produced by generation system which can adjust the applied voltage and radius of testing line. The resulting field signal can be received by receiving system and processed by decoupling algorithm. According to the above method and experimental device, the distribution of space charge density under different factors can be obtained. At the same time, a kind of finite element method is developed to determine the accuracy of the experimental results. And the experimental results turn out to be consistent with the numerical simulation. In addition, the mechanism of affecting factors to the distribution of space charge density can be acquired.

Additional informations

Authors

CHELTSOV, Vörös, LIU, CHIDA

Keywords

space charge, dc transmissiomn, corona discharge, sound wave, various influencing factor