Gas generation properties of oil-paper insulation under pulsating voltage

On-line monitoring of dissolved gas in oil is one of effective methods of condition assessment of transformers. Compared with the power transformer, valve side windings of converter transformer withstand pulsating voltage during the converter process. This paper presents gas generation properties of oil insulation under pulsating voltages, which are different from those under individual AC voltage. Three discharge models were designed and lots of partial discharge experiments were carried out to research the variation characteristics of dissolved gases in oil under pulsating voltages. The increment of gases concentration in oil during the progress of s of different discharge models were analyzed, the experiment results under pulsating voltages showed that the dissolved gas component content was obviously different under pulsating voltage and pure AC voltage. The results can provide the basis experimental data for condition assessment of converter transformer by using the method of online monitoring of dissolved gas in oil.