Set-point control system with override for output of IC engine

摘要

The throttle flap is adjusted by a motor supplied with current from the output stage (14) of a control unit (10) responsive to measurements of accelerator pedal position (32), engine speed (38) and ignition (42). A desired engine load signal is derived (100) and compared (104) with an input representing actual air intake (28). The discrepancy is fed to a regulator (108) such as a three-term controller whose output duty ratio preferably controls the average motor current. A switch (112) operated by another PID controller (140) selects the alternative mode for run-up and full-load phases.