AUTOMATIC ENGINE SPEED CONTROL SYSTEM

摘要

An automatic engine speed hold control system (430) allows an engine (420) to quickly achieve a commanded engine speed and thereafter maintain a constant commanded engine speed regardless of changes in engine loading. An engine speed error signal (444) is computed as the difference between an operator commanded engine speed (440) and actual engine speed (434, 436). The engine speed error signal (444) is scaled based on an engine speed error gain (448), and the scaled engine speed error (452) is then provided via an integral path (456) and a proportional path (454) to a summing junction (478) where it is summed with load anticipation trim signals (474, 467) to provide a final trim signal (485). The load anticipation trim signals (474, 467) are feed forward signals which anticipate engine response to changes in commanded engine loading, the combined engine trim signal (452) and load anticipation trim signals (474, 467) provide an engine speed hold throttle position command (final trim signal) (485) to control fuel flow to the engine (420) and therefore control engine speed. The engine speed error gain (448) is determined based on engine loading (450), and the error gain is thereafter limited (451) based on current engine speed.