Method for measuring leak level of particle filter in gaseous exhaust circuit of internal combustion engine of car, involves estimating soot concentration in exhaust gas flow and leak level of filter from variation of resistance of sensor

摘要

The method involves regenerating an exhaust sensor to destroy agglomerated soots between the electrodes of the sensor. Maximum biasing voltage greater than or equal to 12 V is applied to the sensor for duration. Variation of resistance is measured at terminals of the sensor. Soot concentration in exhaust gas flow and a leak level of filter are estimated from the variation of resistance. The voltage is modified according to the estimation of soot concentration to obtain a signal-to-noise ratio greater than or equal to 100 and a constant saturation time during a measurement cycle.