Patent ID: 6980938

Claim:
A method used in model predictive control applications for removing the effect of unmeasured disturbances from the dynamics of a controller model of a process having a plurality of independently controllable, manipulated variables and at least one controlled variable dependent upon said independently controllable, manipulated variables comprising the steps of: gathering data about said process by separately introducing a test disturbance in each of said manipulated variables and measuring the effect of the disturbances on said controlled variable; using said effects of the disturbances on said controlled variable to generate a first linearized dynamic model relating said at least one controlled variable to said independently controllable, manipulated variables; interchanging selected valve position controlled variables with their corresponding selected independently controllable, manipulated PID controller set point variables in said first linearized dynamic model using matrix row elimination mathematics to generate a second linearized dynamic model that has a new set of independently controllable, manipulated variables, said second linearized dynamic model having the dynamics of said selected independently controllable, manipulated PID controller set point variables removed from said second dynamic model.