Flatness-based end-control of a gas exchange solenoid actuator for IC engines

The control of solenoid valve actuators used for gas exchange in internal combustion engines is considered in this dissertation. Although solenoid valves offer performance benefits over traditional camshaft-based valve systems, an important requirement during operation is to maintain low impact velocity of the armature and valve. The actuator's flat property is exploited in the control design that meets a number of end motion specifications. A flat output, which represents the design parameter, is parameterized with B-spline basis functions using nonlinear programming. A number of motion requirements, nonlinear magnetic effects and voltage constraints are incorporated into the nonlinear feasibility problem to ensure an appropriate position-velocity-acceleration profile results. The resulting flat output provides an open-loop control which is augmented with feedback so that linear stable tracking error dynamics is achieved. The proposed control scheme is demonstrated in simulation and on an experimental testbed.