Patent ID: 11249033

Abstract:
The technical solution relates to measurement technology and is intended for measuring the dielectric permittivity and moisture of highly conductive loose, paste-like and fluid materials such as saline slurry, anthracite, ore, crude oil and oil sludge. The present method is based on using a sensor configured as a segment of a long transmission line, and involves feeding a high-frequency probing signal from a generator that is swept through a range of frequencies to an input of the sensor, and measuring harmonic frequencies at which a length of a signal conductor of the sensor is equal to or a multiple of a half-wavelength of the probing signal in the material filling the sensor. The harmonic frequencies are determined based on a voltage minimum at an output of a detector configured as a phase discriminator, the output voltage of which attains a minimum when input signals of the detector are either in-phase or antiphase. Inputs of the detector are coupled to an input and output of the sensor via segments of a coaxial cable which have the same electrical length, said segments being matched at the outputs. Designs for a moisture meter for carrying out the above method are proposed. For the purpose of carrying out measurements in pipelines, the sensor is configured as a conduit having the signal conductor arranged therein. For loose materials in hoppers and on conveyor belts, the sensor is configured as a shield which a U-shaped rod is secured to. The technical result is an increase of measurement accuracy.