METHOD OF MEASURING GAS CONCENTRATION USING A THERMO-CATALYTIC SENSOR Russian patent published in 2020 - IPC G01N27/16 

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment and can be used in gas analyzers of combustible gases. Method consists in stabilizing temperature of heaters of sensitive and compensating elements of thermocatalytic sensor by changing durations of non-crossing heating pulses by software controlled PWM generators with the same period and using as a feedback signal voltage amplitudes on the sensors of the sensitive and compensation elements of the sensor, made in the form of resistance thermometers. Informative parameters are duration of heating pulses of sensitive and compensating elements. Note here that gas concentration is calculated by expression: C_x=C₀((t_s0-t_s)-C₁(t_c0-t_c)), where t_s0, t_c0 – duration of heating pulses of sensitive and compensation elements of sensor, respectively, determined in the absence of detectable gas and memorized as constants, t_s, t_c – their duration under working conditions; C₁ – constant, calculated through specified pulses duration, determined in the absence of detected gas for two ambient temperatures, and equal to ratio of heat transfer coefficients of sensor elements; C₀ is sensitivity determined by calibrating from reference gas mixture.

EFFECT: high accuracy of measuring concentration of combustible gases with a thermo-catalytic sensor, eliminating physical adjustment of parameters during production.

1 cl, 3 dwg