Fabrication of Thermal Conductivity Detector Based on MEMS for Monitoring Dissolved Gases in Power Transformer

Tingliang Tan; Jianhai Sun; Tingting Chen; Xinxiao Zhang; Xiaofeng Zhu

doi:10.3390/s20010106

Fabrication of Thermal Conductivity Detector Based on MEMS for Monitoring Dissolved Gases in Power Transformer

Sensors (Basel). 2019 Dec 23;20(1):106. doi: 10.3390/s20010106.

Authors

Tingliang Tan^{1

2}, Jianhai Sun¹, Tingting Chen^{1

2}, Xinxiao Zhang^{1

2}, Xiaofeng Zhu³

Affiliations

¹ State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China.
² School of Electronic, Electrical, and Communication Engineering, University of Chinese Academy of Sciences (UCAS), Beijing 100049, China.
³ Beijing Municipal Institute of Labour Protection, Beijing 100054, China.

Abstract

In this work, a high sensitivity micro-thermal conductivity detector (μTCD) with four thermal conductivity cells was proposed. Compared with conventional TCD sensors, the thermal conductivity cell in this work was designed as a streamlined structure; the thermistors were supported by a strong cantilever beam and suspended in the center of the thermal conductivity cell, which was able to greatly reduce the dead volume of the thermal conductivity cell and the heat loss of the substrate, improving the detection sensitivity. The experimental results demonstrated that the μTCD shows good stability and high sensitivity, which could rapidly detect light gases with a detection limit of 10 ppm and a quantitative repeatability of less than 1.1%.

Keywords: dissolved gases; high sensitivity; micro-thermal conductivity detector; microelectromechanical system.