| 摘要 |
<p>Provided is a particulate matter detection device that has a simple structure and can accurately detect the amount of particulate matter that has accumulated. The particulate matter detection device is provided with: a particulate matter sensor (3) which has a capacitance that changes according to the amount of accumulated particulate matter; a bridge circuit (10) which is configured by sequentially connecting a variable resistor (4) and fixed resistors (5-7), connecting the particulate matter sensor (3) in parallel to the variable resistor (4), and connecting a variable capacitor (8) and a compensating member (9) in parallel to the fixed resistor (5) adjacent to the variable resistor (4); and a detector (13) which applies a DC voltage between voltage application points (a, b) to adjust the variable resistor (4) so as to compensate the bridge circuit (10), then applies an AC voltage between the voltage application points (a, b) to adjust the variable capacitor (8) so as to compensate the bridge circuit (10), and detects the amount of accumulated particulate matter from the capacitance of the variable capacitor (8).</p> |
