Adaptive Control of a Pneumatic Valve Actuator for an Internal Combustion Engine

Electro-pneumatic valve actuators are used to eliminate the cam shaft of a traditional internal combustion engine. They are used to control the opening timing, duration, and lift of both intake and exhaust valves. A control oriented model was developed to reduce computational throughput for real-time implementation. The developed control oriented model was validated by experimental data. An adaptive valve lift control strategy was developed to improve lift repeatability. A model reference adaptive system identification technique was employed to calculate system parameters needed for generating closed-loop control signals. The convergence of the derived adaptive parameter identification algorithm was verified using the valve test bench data. The bench test data covers engine speed from 1200 rpm and 5000 rpm. Parameter identification convergence was achieved within 40 cycles. Error between the model and plant outputs were converged to given tolerances. Finally, a closed-loop control strategy was developed and validated in simulation.