Hydrocarbon conversion diagnostic

摘要

A system includes an engine configured to operate in a first operating state and a second operating state, a particulate filter configured to receive exhaust gas from the engine and filter particulate matter from the exhaust gas, and an oxidation catalyst configured to generate heat to increase a temperature of the exhaust gas during a regeneration process. A sensor is configured to measure an actual temperature of the exhaust gas during the regeneration process. A controller is configured to define a fuel conversion factor based, at least in part, on the actual temperature and an expected temperature of the exhaust gas. The controller is further configured to analyze the fuel conversion factor over time relative to at least one of the first and second operating states of the engine and diagnose a fault in the regeneration process based, at least in part, on the fuel conversion factor.

主权项

1. A system comprising:
an engine configured to operate in a first operating state and a second operating state; a particulate filter configured to receive exhaust gas from the engine and filter particulate matter from the exhaust gas; an oxidation catalyst configured to generate heat to increase a temperature of the exhaust gas during a regeneration process; a sensor configured to measure an actual temperature of the exhaust gas during the regeneration process; and a controller configured to:
calculate a fuel conversion factor, the fuel conversion factor representing a ratio of a difference between a first expected temperature of the exhaust gas and a second expected temperature of the exhaust gas to a difference between the actual temperature and the second expected temperature of the exhaust gas;integrate the fuel conversion factor during the regeneration process to define an integration value when the engine is operating in the first operating state;at least one of hold the integration value constant and reset the integration value when the engine is operating in the second operating state;compare the integration value to a predetermined value; andprovide an indication if the integration value is less than the predetermined value.