Title :
Self-calibrating electrochemical gas sensor
Author :
Makadmini, L. ; Horn, M.
Author_Institution :
Univ. der Bundeswehr Munchen, Neubiberg, Germany
Abstract :
A self-calibrating electrochemical gas sensor with an online supervision of the gas sensor´s function, sensor´s sensitivity and sensor´s response time is presented. It leads to an online electrical recalibration and an early detection of an aging dependant sensor failure by detection of the value of sensor´s electrochemical active area. Independent of the gas concentration to be measured, and without spoiling a running operation, the electrochemical active area determining the sensor´s sensitivity and the sensor´s response time is determined online by measuring the electrical impedance of the sensor. The maximal relative error of the estimated sensitivity and the sensor´s response time through the online impedance measurement is small in comparison with the error caused by aging without calibration
Keywords :
ageing; calibration; computerised instrumentation; electric impedance measurement; electrochemical analysis; equivalent circuits; gas sensors; measurement errors; aging; electrical impedance; electrochemical active area; electrochemical gas sensor; maximal relative error; online electrical recalibration; online impedance mesurement; online supervision; response time; self-calibration; sensitivity; test gases; Aging; Area measurement; Calibration; Delay; Electric variables measurement; Gas detectors; Gases; Impedance measurement; Testing; Time measurement;
Conference_Titel :
Solid State Sensors and Actuators, 1997. TRANSDUCERS '97 Chicago., 1997 International Conference on
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-3829-4
DOI :
10.1109/SENSOR.1997.613643
