| 摘要 |
A system for controlling fuel injection in a diesel engine that includes a hydraulically-actuated, electronically-controlled unit injector (HEUI) fuel system. The injection rate/pressure characteristic of a HEUI fuel system is a function of oil supply (rail) pressure, which is independent of engine speed and load. However, transient operating conditions necessitate rapid changes in rail pressure and the prior art system does not always respond to these rapid changes fast enough. The enhanced control system of this invention incorporates a more sophisticated feed forward control term by changing the feed forward calibration from a lookup function based only on desired rail pressure to a lookup table based on desired rail pressure and RPCV flow and which has been found to be responsible for benefits in transient emissions and engine response and performance.
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