Industrial liquid characterization enhancement using microwave sensor equipped with electronic band gap structure

In this paper, we present a novel sensor for permittivity measurement of the industrial liquids to achieve more sensitivity. An electronic band gap (EBG) structure is used. The simulation results show that applying EBG scheme enhances the electric field strength at the measuring part. This issue causes a significant shift in resonant frequency and therefore an increased sensitivity of the designed sensor. The proposed sensor is tested for characterization of liquids with various permittivity and loss tangent values, and the results show the proposed sensor can precisely classify a wide range of liquids in terms of electromagnetic properties. Measurement results indicate that the presented sensor is well suited for transformer oil aging applications.