Abstract: An oxygen sensor controlling apparatus includes: a controller configured to obtain a degradation index of a detection element; obtain a sensor output; detect an internal resistance of the detection element by causing a temporary change between electrodes of the detection element; successively obtain a target resistance value corresponding to the internal resistance using a first sensor output that is a value of the sensor output obtained at a time before or after a period when the temporary change occurs and the degradation index; and feedback control energization of the heater so that the internal resistance becomes the target resistance value.

Abstract: A gas sensor processing apparatus (1) which includes voltage shift means (11, 19, S1071) for shifting a detection element voltage VE produced between electrodes (3P, 3N) of a detection element (3) from a pre-shift voltage VE1 to a post-shift voltage VE2; recovery means (11, 19, S1072) for returning the detection element voltage VE from the post-shift voltage VE2 to the pre-shift voltage VE1 after the end of a voltage shift period TS in which the voltage VE is shifted by the voltage shift means; and deterioration index detection means S106-S107 for detecting a deterioration index ID representing the degree of deterioration of the detection element (3) on the basis of a voltage change in the recovery period TK in which the voltage VE is recovered by the recovery means.

Abstract: When a detection signal obtained from the cell of a gas sensor (S15) has reached a start determination value (specifically, when the output voltage of the cell is higher than 600 mV (S16: YES) or lower than 300 mV (S17: YES)), a pulse voltage is applied to the cell (S18), and a start-time internal resistance is obtained on the basis of the detection signal having changed as a result of application of the pulse voltage (S20). The start-time internal resistance is compared with a deterioration determination value set in advance (S21). A target resistance of the cell used in temperature control (energization control) for the heater is corrected in accordance with the result of the comparison (S28). Thus, the temperature of the cell can be stably maintained constant irrespective of deterioration of the cell.

Abstract: An oxygen sensor controlling apparatus includes: a controller configured to obtain a degradation index of a detection element; obtain a sensor output; detect an internal resistance of the detection element by causing a temporary change between electrodes of the detection element; successively obtain a target resistance value corresponding to the internal resistance using a first sensor output that is a value of the sensor output obtained at a time before or after a period when the temporary change occurs and the degradation index; and feedback control energization of the heater so that the internal resistance becomes the target resistance value.

Abstract: When a detection signal obtained from the cell of a gas sensor (S15) has reached a start determination value (specifically, when the output voltage of the cell is higher than 600 mV (S16: YES) or lower than 300 mV (S17: YES)), a pulse voltage is applied to the cell (S18), and a start-time internal resistance is obtained on the basis of the detection signal having changed as a result of application of the pulse voltage (S20). The start-time internal resistance is compared with a deterioration determination value set in advance (S21). A target resistance of the cell used in temperature control (energization control) for the heater is corrected in accordance with the result of the comparison (S28). Thus, the temperature of the cell can be stably maintained constant irrespective of deterioration of the cell.