Process reaction curve approach to approximate high-order (linear or nonlinear) systems with a first-order-plus-timedelay model using step response data. It also provides an example of PID controller design using the approximate model based on the classical tuning table. It can be easily replaced with any other more advanced tuning tables based on the same approximate model.
I compared the ReactionCurve.m output response to various other methods i.e. Sundaresan, K.R. and Krishnaswamy, P.R. (1978) method, the manual point of inflection by inspection method and the two-point method from Smith, C.L. (1972)all of which produced a better fit to my plant model. The best fit was produced from the Sundaresan, K.R. and Krishnaswamy, P.R. (1978) method.
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