Cross Direction (CD)

Overview 
Performance CD control is a multivariable control solution specifically designed for paper-making processes and used for co-ordination of multiple CD actuator beams optimizing multiple sheet properties. It uses a model of each actuator’s effect on each sheet property and takes the physical limitations of the actuator explicitly into account when calculating new optimal actuator setpoints. Performance CD control is a model predictive controller and after each measurement scan it calculates optimal setpoints that will minimize future predicted variation in the sheet properties. To ensure that all controllable variation is seen by the controller, all calculations are performed using high resolution profile information to avoid loss of data through filtering. Sustainable mapping of CD control is ensured by unique adaptive alignment functionality that continuously monitors the control performance to detect significant changes in actuator alignment. This occurs in the background during normal production operations, with the CD controls in closed loop and has zero impact on production quality. 
Performance CD Control comes with award-winning IntelliMap® tool for easy commissioning and maintenance. IntelliMap automates bump tests to identify the actuators’ responses in all downstream measured profiles and automatically calculates the global process model as well as optimization parameters based on simple user inputs for maximum overall CD performance. IntelliMap allows user to simulate new process model and optimization settings prior to parameter deployment. 
Performance CD control is highly scalable from single weight and moisture control loops up to holistic paper machine profile optimization solution including calendaring, coating, pulp dryer bale profile optimization, fiber orientation control and so on. It is available on Honeywell QCS platforms as well as standalone offering for customers with 3rd party QCS. 

What Problems Does It Solve? 
Honeywell’s unique Performance CD Control solution is designed to maximize each actuator’s contribution for holistic product quality and production efficiency. Tight coordination of all actuator beams increases speed of recovery from process upsets and allows economic targets to be pushed way beyond what is achievable with traditional technology.  
Advanced optimization features of Performance CD Control technology enable potential energy savings, target shifts and production increases on paper-making process while adaptive alignment and easy-to-use IntelliMap tool provide long term control performance and reduces maintenance costs hence improving total cost of ownership of the CD optimization solution.