Control and Process System Identification

Reference signal (r,) This represents the desired or set point value for the process. 

Input signal (u This represents the input into the process. This signal can also be called the manipulated variable. 

Disturbance signal (e,) This represents the unmodelled changes in the process. The disturbance signal is often assumed to be a Gaussian, white noise signal with zero mean and variance 

Process (Gp) This gives the known model of the process. 

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