Pressure control within an industrial plasticating extruder

Describes the design of a control strategy for an extruder gearpump arrangement which yields substantial improvement in operation. The controller design is based on the discrete optimal regulator solution and includes automatic dead-time compensation. The selection of an appropriate sampling time is obviously important in any discrete time design and the paper presents the results of an algorithm for automatic selection of the most appropriate sampling time. To provide realistic comparison of the performance of this strategy with the existing PI feedforward implementation a simple extension to a optimal regulation strategy which includes feedforward action is presented