| 摘要 |
PROBLEM TO BE SOLVED: To effectively detect an exhaust humidity without using a humidity sensor, with respect to a state detecting device of an exhaust system.SOLUTION: A state detecting device includes a DPF (diesel particulate filter) 16 for collecting a PM (particulate matter), temperature sensors 31, 32, electrostatic capacity detection units 17a, 17b, 21 detecting an electrostatic capacity of the DPF 16, and an exhaust humidity calculating portion 23 for calculating an amount of water molecule corresponding to the temperatures detected by the temperature sensors 31, 32, and the electrostatic capacity detected by the electrostatic capacity detecting units 17a, 17b, 21, on the basis of a characteristic map in which the relationship of the temperature of the DPF 16, the electrostatic capacity of the DPF 16, and the amount of water molecule existing in a DPF portion, is determined in advance. |
