Applicability of semiconductor gas sensor for measurement of dissolved hydrogen gas in oil

This paper describes applicability of semiconductor gas sensor for measurement of dissolved hydrogen gas in oil. On line gas measurement is useful for continuous monitoring of power transformer. Recently many studies on application of hydrogen gas sensors, due to their simplicity and low price, have been done for that purpose. In general responses of semiconductor gas sensors are affected by ambient temperature and humidity and sensing element material. That is, these result in affecting conductivities of the sensors which determine gas concentrations. As the ambient temperature and humidity around power transformers are always changed, it is very important to analyze gas sensing characteristics with their changes to improve measurement of the gas concentrations. In this study, commercial gas sensors are used to study relations between sensor output and circumstances such as temperature or humidity. It is indicated that the increase of ambient temperatures increased the output voltages of gas sensor at same hydrogen gas concentration but any trend of the voltages with humidity was not shown.