Summary

In this paper, a measurement system will be presented, that is able to record the electric and optic properties of pre-discharge on both rod electrodes simultaneously. The measurement has been carried out with long air gaps up to 3 m and voltages up to 2.4 MV (positive and negative polarities). The experimental setup is divided into three parts: voltage generation and measurement part, photographical part and pre-discharge current measurement (positive and negative) part. The focus of this paper will be mainly on the challenges, difficulties, solutions and finally the description of the constructed pre-discharge-current-measurement units. Each pre-discharge current measurement part (positive or negative) consists a measuring, a power supply, and a communication unit. The measuring unit contains an oscilloscope for recording the pre-discharge current at the rod electrode. The measurement succeeds over wide frequency range up to 200 MHz. It is configured to measure the pre-discharge currents, presumed to be in milliampere-range. Gas discharge tubes are used to protect the system against the breakdown current. The communication unit connects both oscilloscopes through fibre optic cables and ensures a synchronisation of two current measurements in nanosecond-range. Furthermore, both oscilloscopes should be remotely controlled by a computer outside of the measuring cell. In order to minimize external disturbances as well as to protect the system against electromagnetic disturbances, the pre-discharge current measurement part is enclosed by a metal box and is fed by a separate power supply system. It includes a battery and a dc/ac-converter. In this work, some of the recorded currents and taken photographs are shown representatively. Based on the recorded currents and photographs, streamer and leader or a kind of a discharge channel and the breakdown can be differentiated.

Additional informations

Publication type ISH Collection
Reference ISH2015_396
Publication year 2015
Publisher ISH
File size 2 MB
Price for non member Free
Price for member Free

Authors

Ma Qiyan, Han Ya'nan, Wang Song, Jingxin Zou

A measurement system for investigation of the breakdown process of lightning impulses on the rod-rod electrode
A measurement system for investigation of the breakdown process of lightning impulses on the rod-rod electrode