Cycle adaptive feedforward approach control of an electromagnetic valve actuator

An electromagnetic valvetrain on an internal combustion engine can improve the engine thermal efficiency but requires control to achieve soft landing and to avoid excessive wear and noise. Since the valves open and close repetitively, cycle adaptive control can be utilized. A cyclic adaptive feedforward approach controller for automotive electromagnetic valve is presented. This method uses a Nelder-Mead direct search algorithm with the goal of setting constant initial conditions for the landing control. Simulation and testbench results are presented and they show that the approach control works well for disturbances that are slow compared to the valve travel time. © 2008 IEEE