This type of sensor applies the principle of thermal conductivity detection. The core detection component is a constant temperature thermal conductivity sensor with temperature compensation function. The thermal conductivity sensor consists of two chambers, each with an identical thermal conductivity meter. One of the chambers is sealed and filled with reference gas, while the other chamber receives sample gas. The controller converts the difference in thermal conductivity between the reference gas and the sample gas into the current concentration value of the detection sample gas. As used for detectionHydrogen in oxygen, the curved detection range can be any range from 0-1% to 0-5%. Other customized ranges can also be made.