摘要 |
<p>A particulate collection filter state detection device according to the present invention includes first pressure detection means for detecting a first pressure produced at an upstream side of the filter on an exhaust gas flow path, second pressure detection means for detecting a second pressure produced at a downstream side of the filter on the exhaust gas flow path, first Fourier transformation means for applying Fourier transformation to a value of the first pressure detected by the first pressure detection means, second Fourier transformation means for applying Fourier transformation to a value of the second pressure detected by the second pressure detection means, comparison means for comparing a spectral intensity and/or a phase at a zero frequency and a spectral intensity and/or a phase at a predetermined frequency obtained by the first Fourier transformation means and a spectral intensity and/or a phase at a zero frequency and a spectral intensity and/or a phase at a predetermined frequency obtained by the second Fourier transformation means, and filter state determination means for determining a state of the filter based on a comparison result provided by the comparison means, so as to conduct determination of a state of a filter for collecting particulates in an exhaust gas at a good precision.</p> |