Three hypotheses about steady-state response

transient response and resuming behavior of the semiconductor gas sensor are proposed

according to which

the logarithm of the steady-state resistance value and the logarithm of the gases concentration obey the tangent function

the transient response is determined by the current resistance of the sensor and the gases concentration

while the resuming behavior is determined by the current resistance of the sensor and gas concentration at the next interval. In order to validate the hypotheses

gases separating function is then modeled based ob the stage model. Relative coefficients are obtained by experiment and mathematical methods. The gas separating model and the three hypotheses are validated by comparing the simulating results with the experimental ones

which shows that the hypotheses are rational as seen in their application in the semiconductor of the monitoring system for dissolved gases in insulation oil.