How to draw Bode Plot | Solved Example

Ram Swaroop February 19, 2018

Bode plot has two parts- gain plot and phase plot. We will learn how to plot bode plot step-by-step by using a solved example. Just be patient.

Bode gain plot :- is a plot of 20 log₁₀ |G(jw)| ( db) against frequency w(rad/sec) on a semilog paper. The frequency is plotted on horizontal log scale and gain on vertical linear scale.

Step-1 :- obtain the open-loop transfer function (OLTF) of the control system under consideration. Let the OLTF be

If we add all the plotted individual plots, we get bode gain plot for given transfer function. The complete bode gain plot is given below.

Bode Phase plot :- is a plot of ∠G(jw) against the frequency w(rad/sec.) on a semilog paper. The frequency is plotted on log scale and phase on vertical linear scale.