A Comparative Analysis of PID, Lead, Lag, Lead-Lag, and Cascaded Lead Controllers for a Drug Infusion System

Figure 4

Graphical illustration of root locus existence shaping and the concept of pole zero placement using a pseudo system S and a pseudo lag controller C.

(a) Root locus existence using two poles of a system S

(b) Pole zero placement using system S and controller C with root locus shaping

(c) Pole zero placement using system S and controller C with no root locus shaping