Root Locus Practical Sketching Rules for Fractional-Order Systems

Figure 2

Riemann surfaces: (a) 𝑃(𝑠^𝛼)=𝑠^1/2+1 has two sheets; (b) 𝑃(𝑠^𝛼)=𝑠^4/3+1 has three sheets.

(a)

(b)