DIRECT INJECTION PUMP CONTROL FOR LOW FUEL PUMPING VOLUMES

摘要

Methods are provided for controlling a solenoid spill valve of a direct injection fuel pump, wherein the solenoid spill valve is energized and de-energized according to certain conditions. A control strategy is needed to operate the direct injection fuel pump when small fractional trapping volumes are commanded, wherein a small amount of fuel is compressed and sent to the direct injection fuel rail. To maintain reliable and repeatable solenoid spill valve behavior for small fractional trapping volumes, methods are proposed that involve energizing the solenoid spill valve for a minimum angular duration below a trapping volume fraction threshold.

主权项

1. A method, comprising:
during a first condition, energizing a solenoid spill valve of a direct injection fuel pump for only an angular duration based on a position of a piston of the direct injection fuel pump; and during a second condition, energizing the solenoid spill valve for or longer than a minimum angular duration, wherein the solenoid spill valve is deactivated after a top-dead-center position of the piston is reached.