Integrator plus Dead Time System

With dynamic systems that are non-self-regulating one finds, likewise, step responses with and without dead time. An integrator plus dead time process would be modeled like Eq. (77). 

For a step-change in input flow rate of magnitude M the system becomes as in Eqs. (78), the solution to which is Eq. (79). 

The parameters for this process may be obtained from a step test. At time to the steady-state input to the process is stepped by an amount and the gain Kp is found from the measured slope [Eq. (80)]. 

The dead time 6 is the delay in the response after the input step at time to. 12.4.3 

Controllers are devices that are meant to keep a specific controlled variable constant despite outside disturbances. One differentiates between continuous, digital, and On-Off controllers, depending on whether the output is continuous, discrete, or on-off. The great majority of controllers have been continuous, but the digital controller is now commonplace due to the widespread use of computers and distributed control systems. 

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