Analytic PID Design
description
Transcript of Analytic PID Design
-
Analytic PID DesignIf G(s) is the loop gain, then the characteristic equation can be written as
We want to find the value of kp, kd, and ki to place a pole of the characteristic equation at a specified location, s1. Inother words, we want to find the value of s1 that satisfies
If we consider the controller
Equation 1
but s1 is also a complex number that can be represented by a magnitude and a phase:
Rewriting equation 1 gives us
Assume we can pick ki based on some other criterion, we can rewrite the equation
Equating real and imaginary parts of this last equation gives us a set of two equations in two unknowns (since ki isknown).
Analytic PID Design file:///C:/Documents and Settings/Win XP/Desktop/Survey_PID/Lectur...
1 de 2 12/3/2012 22:33
-
If s1 and ki are known, they can be used to find M, q, B and b, and the equations can be solved for kp and kd. Doinga little algebra yields the general result that
Analytic PID Design file:///C:/Documents and Settings/Win XP/Desktop/Survey_PID/Lectur...
2 de 2 12/3/2012 22:33