Cummins Inc.
SYSTEMS AND METHODS FOR REDUCING RAIL PRESSURE IN A COMMON RAIL FUEL SYSTEM

Abstract:

Methods and systems, using a controller (20), for performing fuel pressure control operation of an engine (12) having at least one cylinder (16) is disclosed. The controller (20) includes a fuel system control unit (42) configured to control a fuel pressure applied to at least one injector (18) of the engine (12) during a motoring condition period (412) based on a commanded pulse train duration (410). During the motoring condition period (412), no combustion occurs in the at least one cylinder (16) of the engine (12). The commanded pulse train duration is a time period during which the at least one injector (18) of the engine (12) is activated for a drain operation. The fuel system control unit (42) is configured to command the at least one injector (18), for the commanded pulse train duration during the motoring condition period (412), to release fuel from the at least one injector (18) without injecting the fuel into the at least one cylinder (16) of the engine (12).