5.2 Root Locus Analysis

  • The locus of the roots of the closed loop system as a function of a system parameter, as it is varied from 0 to infinity results in the Root-Locus.

  • Root-loci start at open-loop poles and end at open-loop zeros. If there are more number of poles(\(n\)) than zeros(\(m\)), i.e., \(n>m\), then \(n-m\) loci end at infinity.

  • The root locus is symmetrical with respect to the horizontal real axis (because roots are either real or complex conjugate).