Gas sensor and method for controlling gas sensor

摘要

Disclosed is a method for controlling a gas sensor (100A) comprising the steps of pumping-processing oxygen contained in a measurement gas introduced from external space into a first chamber (110) by using a main pumping cell (118) so that a partial pressure of oxygen in the first chamber (110) is controlled to have a predetermined value at which a predetermined gas component as a measurement objective is not decomposable; decomposing the predetermined gas component contained in the measurement gas in a second chamber (112) by the aid of a catalytic action and/or electrolysis by using a detecting pumping cell (134) to pumping-process oxygen produced during the decomposition; and measuring the predetermined gas component contained in the measurement gas on the basis of a pumping current (Ip2) which flows during the pumping process; wherein the oxygen to be pumped out by the detecting pumping cell (134) is pumped out toward an inner pumping electrode (114) which is fixed to have a base electric potential (ground electric potential), of the main pumping cell (118). Accordingly, it is possible to facilitate miniaturization of a control circuit system of the gas sensor and reduction of the weight thereof. <IMAGE>