Expert system for integrated control and supervision of dry-end sections of paper machines

A rule-based expert system for the integrated control and supervision of the dry-end sections of a paper machine is proposed. This system is capable of recognizing all the normal and abnormal changes in process operating conditions, including acceleration of sections, threading of paper sheet, nip pressure activation, activation and deactivation of tension control loops, change of parent roll, and sheet break. A core part of the system is the supervision of the sensorless tension control of the dry-end sections, assuring its long-term stability.