METHOD OF DETERMINING LEVEL OF DIELECTRIC SUBSTANCE Russian patent published in 2012 - IPC G01F23/26 G01R17/10 

FIELD: physics.

SUBSTANCE: method of determining level of a dielectric substance involves generation of sinusoidal voltages across a capacitance level sensor, measuring current through the a capacitance level sensor and measuring current through a filled capacitance level sensor. When measuring current through a dry capacitance level sensor and the reference and during periodic measurement and recording of current through a capacitance level sensor filled with a dielectric substance (during refill) and the reference, the capacitance level sensor and the reference are successively exposed to sinusoidal voltages at an n-1 fixed frequency (where n is the number of elements of the two-terminal network in the equivalent circuit). Further, using constant voltage, during each exposure to voltages, current through the capacitance level sensor and the reference is successively measured, after which measurement results are recorded. Voltage across the capacitance level sensor and the reference is removed. Bias current on the capacitance level sensor and the reference is measured and measurement results are recorded. Further, the difference in current values measured from the results of exposing the capacitance level sensor and the reference to sinusoidal and constant voltages and the corresponding bias current values are determined. The obtained current difference values are recorded, and determination and recording of electrical parameters (i.e., capacitance and insulation resistance) and relative filling of the capacitance level sensor are carried out based on the recorded current measurement results, including bias current through the two-terminal network and the reference using mathematical expressions deduced from analysis of the vector diagram of the equivalent circuit.

EFFECT: high accuracy of level determination, lying elimination of the effect of length of the communication line and bias current on the determination result, high technological effectiveness of level determination, lying in full automation of the level determination process, eliminating the human factor and a manual procedure for adjusting measurement apparatus.

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