Method of controlling a fuel supply system

摘要

A system and method for controlling a fuel supply system of an engine is disclosed in which an engine driven high pressure fuel pump is operated whenever possible at one of an optimum demand level providing optimum pump efficiency for the current engine speed or at a zero demand level to reduce the fuel used by the engine to drive the high pressure fuel pump. The operating mode used is dependent upon at least one of the amount of fuel currently stored in a high pressure fuel accumulator and whether a current fuel demand Fd exceeds an optimum quantity Po of fuel that can be provided by the high pressure fuel pump when operating at the current engine speed.

主权项

1. A method, comprising:
operating an engine driven fuel pump at one of a zero demand level and an optimum demand level while using a valve to control a fuel flow from the fuel pump and an accumulator to meet an engine fuel demand; and operating the fuel pump above its optimal level when the accumulator is empty and the fuel demand is greater than fuel available from the optimally operated fuel pump, including operating the fuel pump inefficiently compared to the optimal level to provide fuel to only an engine while preventing flow to the accumulator.