-
In the root-locus for open-loop transfer function
G(s) H(s) = K(s + 6) (s + 3)(s + 5)
The ‘break away’ and ‘break-in’, points are located respectively at
-
- – 2 and – 1
- – 2.47 and – 3.77
- – 4.27 and – 7.23
- – 7.73 and – 4.27
Correct Option: D
Both the answers (c) and (d) are idential. The breakaway and breakin points on the root locus for which loop transfer function is G (s) H (s) are obtained as a solution of equation
| G(s) H(s) = 0 | ||
| ds |
⇒ (s + 6) (2s + 8) – (s2 + 8s + 15) = 0
⇒ 2s2 + 20s + 48 – s2 – 8s + 15 = 0
⇒ s2 + 12s + 33 = 0
∴ s = – 7.73 and – 4.27
