The sensor includes a filter member including cells that trap PM in exhaust gas; electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration of heating the cells to combust and remove the PM, a storage unit that stores a reference reduction amount, which is an electrostatic capacitance reduction amount between the electrode members in a case where the filter regeneration is executed in a state where the PM is not flowing into the filter member, and estimation units that estimate a PM amount based on (a) an actual electrostatic capacitance change amount between the electrode members during a regeneration interval period, and (b) a difference between an actual electrostatic capacitance reduction amount between the electrode members and the reference reduction amount during a filter regeneration period.

Methods and systems are provided for sensing particulate matter in an exhaust system of a vehicle. An example system comprises a particulate matter sensor inside a tube configured to receive a portion of exhaust gas in an exhaust passage.

A method of operating a particulate matter sensor having a pair of spaced apart electrodes and a heater includes accumulating particulate matter on the sensor, thereby changing resistance between the pair of spaced apart electrodes. The particulate matter sensor includes a sensing cycle that includes a deadband zone, followed by an active zone, which is followed by a regeneration zone in which the heater is operated to elevate the temperature of the particulate matter sensor to a first predetermined temperature for a first predetermined time in order to oxidize the particulate matter accumulated on the particulate matter sensor. The method also includes interrupting the sensing cycle with a modified regeneration zone which is either higher in temperature or length than the regeneration zone.

An exhaust gas aftertreatment system includes: a first sensor configured to measure a parameter in the exhaust gas aftertreatment system; a second sensor configured to measure the parameter in the exhaust gas aftertreatment system, the second sensor disposed proximate the first sensor; and at least one controller configured to simultaneously receive sensor values from the first sensor and receive sensor values from the second sensor.

The present disclosure relates to a system, apparatus, and method for reconditioning a particulate matter sensor in an exhaust aftertreatment system that will resist poisoning. The system and method includes receiving particulate matter data indicating a state of the particulate matter sensor; determining that the particulate matter sensor is in a full state based on the particulate matter data; activating a heating element of the particulate matter sensor to a multiple of intermittent temperatures that clean the sensor pre-patory to the next measurement. By this manner, many reactive chemicals are removed before they can react with and poison the sensor materials.

To enable an improved operating behavior of an internal combustion engine, an internal combustion engine having at least one combustion chamber, having at least one air inlet section for the supply of air into the combustion chamber, having at least one exhaust gas outlet for the discharge of exhaust gas into at least one exhaust gas tube, having at least one optical particulate measurement sensor, and having a control apparatus for controlling an operating behavior of the internal combustion engine is provided, wherein the optical particulate measurement sensor is provided to determine a particulate concentration in the exhaust gas and to make available at least one particulate concentration signal for the control apparatus derived from the particulate concentration and wherein the control apparatus is configured to directly change the operating behavior of the internal combustion engine based on the particulate concentration signal of the optical particulate measurement sensor.

Methods and systems are provided for a particulate matter (PM) sensor assembly positioned downstream of a diesel particulate filter in an exhaust system. In one example, a method may include rotating the PM sensor assembly inside an exhaust passage to generate an output, the rotation based on exhaust flow conditions within the exhaust passage. By rotating the PM sensor assembly via a bearing, a rate of soot particulate accumulation on a sensor element of the assembly may be maintained at a desired level, and independent of a direction of exhaust flow inside the exhaust passage.

An exhaust aftertreatment system includes a particulate filter element and a particulate matter sensor that is disposed to monitor the exhaust gas feedstream downstream of the particulate filter element. A method for monitoring the exhaust gas feedstream includes determining a temperature associated with the particulate matter sensor and monitoring engine operation and the exhaust aftertreatment system. A magnitude of ammonia is determined in the exhaust gas feedstream proximal to the particulate matter sensor based upon the monitoring of the engine operation and the exhaust aftertreatment system. An initial reading is determined from the particulate matter sensor and is adjusted based upon the magnitude of ammonia in the exhaust gas feedstream proximal to the particulate matter sensor and the temperature of the particulate matter sensor. A magnitude of particulate matter in the exhaust gas feedstream is determined based upon the adjusted initial reading from the particulate matter sensor.

Methods and systems are provided for monitoring and adapting sensors and actuators in the induction system and exhaust system of an internal combustion engine during a period of time in which fresh air is flowing through the internal combustion engine without fuel delivery. According to the disclosure, the period of time in which fresh air is flowing through the internal combustion engine when fuel delivery is turned off and the monitoring and adapting is being carried out is extended by transferring torque produced by electric motor to the internal combustion engine.

A particulate matter (PM) sensor unit may include an exhaust line where exhaust gas passes, and a PM sensor that may be disposed at one side of the exhaust line and that generates a signal when particulate matter included in the exhaust gas passes the vicinity thereof, wherein the PM sensor may be an electrostatic induction type that generates an induction charge while the particulate matter having an electric charge passes the vicinity thereof.