Apparatus, method, and system for diagnosing reductant delivery performance

摘要

A system for diagnosing and/or determining the performance of a reductant delivery system may include determining a flow rate offset value for the reductant delivery system. A reduced reductant flow rate may be determined for a reductant dosing command value based, at least in part, on the determined flow rate offset when reductant dosing command is non-zero. A reductant flow rate error can be determined based, at least in part, on a difference between an expected reductant flow rate value corresponding to the reductant dosing command value and the determined reduced reductant flow rate. A performance status value indicative of a performance status of the reductant delivery system may be outputted based, at least in part, on the determined first reductant flow rate error and a predetermined threshold.

主权项

1. A system for diagnosing performance of a reductant delivery system, comprising:
a reductant delivery system comprising a reductant pump; and a controller configured to:
determine a reductant flow rate offset value for the reductant delivery system, the reductant flow rate offset value based on a first pump command value for the reductant pump when an output pressure value from a pressure sensor is stabilized and a first reductant dosing command value controlling an amount of reductant to a delivery mechanism of the reductant delivery system is zero,determine a first reduced reductant flow rate for a second reductant dosing command value based, at least in part, on the determined reductant flow rate offset value, the second reductant dosing command being non-zero,determine a first reductant flow rate error based, at least in part, on a difference between a reductant flow rate value corresponding to the second reductant dosing command value and the first determined reduced reductant flow rate, and output a performance status value indicative of a performance status of the reductant delivery system based, at least in part, on the determined first reductant flow rate error and a predetermined threshold.