METHOD OF MEASURING GAS CONCENTRATION BY A CATALYTIC SENSOR Russian patent published in 2019 - IPC G01N27/12 

FIELD: gas analyzers.

SUBSTANCE: use: for use in gas analyzers of combustible gases. Essence of the invention consists in the fact that the method consists in stabilizing the temperature of the heater of the sensitive element of the sensor by varying the duty ratio of the program-controlled PWM generator using, as a feedback signal, the voltage amplitude on the heater of the sensor element, made in the form of a resistance thermometer, concentration of combustible gases is determined through difference in duration of PWM pulses, which maintain constant temperature of sensitive element of sensor in presence of combustible gases and their absence, wherein the latter is determined by calculation method through values of pulse duration PWM determined during calibration and stored in microcontroller memory for two different ambient temperatures and values of temperatures, as well as by current value of ambient temperature, wherein temperature sensor must have stable sensitivity and linear characteristic.

EFFECT: higher accuracy of measuring concentration of combustible gases by a catalytic sensor.

1 cl, 2 dwg