The ultra high voltage device with vacuum insulation

The ultra high voltage transmission lines rated 1000kV will be the effective and practical strategy for the interconnection of the national wide power grid in China. In order to test the equipment with ultra high voltage the synthesis circuit which uses voltage and current source to work together will be adopted because of the lower test cost. The very important device which will determine and influence the validity of the synthesis circuit test will be introduced and designed in this paper. The voltage is high so the gap in air will be very long to sustain such high voltage even in vacuum the gap will also be long enough. Long gap is not easy to be influenced by the tripping signal. The simulation test is carried out with air gaps in series. The function of the tripping signal on the breakdown of the gaps is tested. The minimum breakdown voltage is tested and compared between the same gap with and without tripping signal. The relationship of the voltage smaller than the minimum breakdown voltage and the breakdown time is also tested. The test result proves that tripping signal can control the breakdown time of the gaps in series, which will be true for the long vacuum gaps in series. Furthermore the tripped vacuum gaps in series rated 500kV with 3.8m long is designed