Patent classifications
F01N2900/0416
BLEED CANISTER OF A VEHICLE EVAPORATIVE EMISSIONS CONTROL SYSTEM
Methods and systems are provided for carrying out diagnostics of a bleed canister of an evaporative emissions control system in a vehicle. In one example, a method may include, loading the bleed canister during a refueling event, and then during an immediately subsequent engine start, detecting if the bleed canister is degraded or not based on output of an exhaust gas oxygen sensor.
Catalyst degradation detection apparatus
A catalyst degradation detection apparatus includes an air-fuel ratio detector disposed downstream of a catalyst and configured to detect an air-fuel ratio of exhaust gas flowing out from the catalyst, and an electronic control unit configured to control an air-fuel ratio of inflow exhaust gas flowing into the catalyst and determine whether the catalyst is degraded. The electronic control unit is configured to execute degradation determination control that brings the air-fuel ratio of the inflow exhaust gas to an air-fuel ratio leaner or richer than a stoichiometric air-fuel ratio. The electronic control unit is configured to determine whether precious metal of the catalyst is degraded based on the air-fuel ratio detected by the air-fuel ratio detector when an oxygen storage amount of the catalyst is varying in the degradation determination control.
METHOD FOR REDUCING DEPOSITS RELATED TO A REDUCTION AGENT IN A PORTION OF AN EXHAUST AFTERTREATMENT SYSTEM
A method for reducing deposits related to a reduction agent (RA) in a portion of an exhaust aftertreatment system (EAS) of an internal combustion engine (ICE) and comprising an injector for injecting the RA into said EAS, said portion located downstream of said injector, as seen in an intended direction of flow of exhaust gas in said EAS, said method comprising: identifying for said ICE, a future operating sequence (FOS) comprising a first temporal portion (t.sub.1) and a second temporal portion (t.sub.2) subsequent to t.sub.1, confirming that said FOS is suitable for reducing deposits and that said ICE operates in accordance with said FOS, in response to said confirming being affirmative, injecting a first dosage (d.sub.1) of RA into said EAS during at least a part of said t.sub.1 and injecting a second dosage (d.sub.2) of RA smaller than d.sub.1 into said EAS during at least a part of t.sub.2.
METHOD FOR DETECTING A SENSOR ANOMALITY
A computer implemented method for anomality detection at a first nitrogen oxide (NOx) sensor forming part of an exhaust gas aftertreatment system (EATS) is provided. The EATS is coupled downstream of an internal combustion engine (ICE). The disclosed methodology applies manipulation of the ICE for detecting such a possible anomality.
Temperature estimation for sensor
A process for controlled heating of a sensor of an aftertreatment system comprising accessing several parameters, including an exhaust mass flow, an outlet temperature, an ambient air temperature, and an ambient air velocity, calculating a temperature of the sensor based on a thermal model and the accessed parameters, comparing the calculated temperature to a threshold temperature, and activating a controlled heating process for the sensor responsive to the calculated temperature being below the threshold temperature. The controlled heating process can include activating a heater to heat the sensor.
Method for Determining a State Parameter of an Exhaust Gas Sensor
Various embodiments of the teachings herein include a method for determining a state parameter of an exhaust gas sensor with a sensor element and a heating device arranged in the sensor element for heating the sensor element. The heating device is electrically connected via a first electrical line and a second electrical line to a control device for electrically controlling the heating device. The heating device includes a measuring line electrically connected between the control device and the first electrical line for controlling the temperature-dependent resistance of the heating section. The method may include: determining a measurement voltage dropped between the first electrical line and the measuring line; determining a compensation voltage on the basis of a predetermined reference voltage and the determined measurement voltage; and determining the state parameter of the exhaust gas sensor by assigning the determined compensation voltage to the state parameter.
Controller and method for controlling operation of an aftertreatment system based on short-term and long-term cumulative degradation estimates
A controller for controlling operation of an aftertreatment system that is configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to: generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter; generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter; generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate of the SCR catalyst.
Methods for making and using SCR catalyst on-board diagnostic limit parts
A method of manufacturing an on-board diagnostic (OBD) limit part and a method of testing to evaluate an OBD system. The method of manufacturing the OBD limit part includes introducing a contaminant to a selective catalytic reduction (SCR) catalyst and contacting the contaminant with the SCR catalyst for a selected period of time. The method of manufacturing utilizes a vessel, the contaminant, and the SCR catalyst. The OBD limit part is a combination of the contaminant and the SCR catalyst within the vessel. The method of testing to evaluate the OBD system includes collecting data related to an exhaust gas before and after the exhaust gas is exposed to the OBD limit part, collecting an indication provided by the OBD system, and comparing the data related to the exhaust gas and the indication provided by the OBD system. The method of testing to evaluate the OBD system utilizes a system that includes an exhaust gas source, a first and a second fluid path, the OBD limit part, and the OBD system.
DEF thawing apparatus and method for diesel engine SCR systems
A Diesel Emissions Fluid (DEF) Thawing arrangement is provided for use with a vehicle having an engine, an Engine Control Module (ECM), an exhaust system, and an SCR catalytic device. A DEF injection system is connected to the exhaust system and to the ECM. A DEF tank is connected to the DEF injection system. An exhaust pipe branch is connected to the exhaust system. A heat exchanging apparatus is connected to the exhaust pipe branch and is configured to exchange heat from exhaust gas within the exhaust pipe branch to the DEF in the DEF tank. The heat exchanging apparatus may be an exhaust gas to DEF heat exchanger located at least partially within the DEF tank, or may be an exhaust gas to coolant heat exchanger connected to an engine coolant circuit and a coolant to DEF heat exchanger located at least partially within the DEF tank.
Control apparatus
In a control apparatus, a heater adjuster performs a regeneration task of causing a heater to heat a sensing member of a particulate matter sensor to burn particulate matter deposited on the sensing member to thereby remove the particulate matter from the sensing member. The heater adjuster performs a deposition reduction task of maintaining, for a predetermined duration, a temperature of the sensing member at a deposition reduction temperature that reduces additional particulate-matter deposition on the sensing member. The predetermined duration is defined from completion of a regeneration task to a time when an environmental condition around the particulate matter sensor is determined to be stable. The heater adjuster stops the heater from heating the sensing member if a condition determiner determines that the environmental condition around the particulate matter sensor is stable.