| 摘要 |
PROBLEM TO BE SOLVED: To improve estimated accuracy of the element temperature in the estimation of the element temperature, by temporarily applying a voltage for measuring the element temperature to a sensor element of an air/fuel ratio sensor, to calculate the internal resistance of the sensor element from a sensor output Vr during the application of the voltage. SOLUTION: A sensor output Vs, immediately prior to the application of the voltage, is read in to make a correction based on it. More specifically, the sensor output Vaf immediately prior to the application of the voltage is subtracted from the sensor output Vr during the application of the voltage to calculate the sensor output Vr after the correction = Vr-Vaf. The process from the calculation of the internal resistance to the calculation of the element temperature is carried out based on the results. In the process from the calculation of the internal resistance to the calculation of the element temperature according to the sensor output Vr during the application of the voltage, the internal resistance or the element temperature calculated is corrected, based on the sensor output Vaf immediately prior to the application of the voltage. |
