Exhaust heating control

摘要

Control of a fuel rate and an air rate delivered to an exhaust gas heater over successive control periods by determining and periodically updating a desired heater air quantity and a desired heater air/fuel ratio, by commanding an air rate in accord with the desired heater air quantity, by adjusting the commanded air rate in accord with a sensed actual air rate, and by commanding a fuel quantity in accord with the desired heater air/fuel ratio and the sensed actual air rate or the desired heater air quantity. A quantity of excess fuel is purged from the system at the end of a control period and provided in usable form to the engine. Compensation for fuel residue in the system is made at the start of subsequent control periods.