Automatic process control and noise suppression

A method of controlling a process of making a material to a nominal property value using control configuration of a Smith Linear Predictor which employs an undelayed estimate of the property value, a measurement of the property value in a delayed time frame, and a delay buffer that places said estimate in the time frame of the delayed measurement of said property value, wherein the improvement comprises:

• providing a feedback model of the process that includes a state observer and no transfer function model;
• using said state observer in an undelayed time frame to estimate the property value as a function of at least one measurable variable of the process observed by the state observer to eliminate the influence of transport delay of the material on controlling the process to said nominal property value;
• eliminating any influence of model errors in the state observer on the control process by using a delay buffer that models transport delay in a manner that places said estimate of the property value in the time frame of the delayed measurable variable;
• and
• using said estimate to control the process to said nominal property value.