How do I obtain the bode plot of the given transfer function?

Given the transfer function below, how can I graph it on Matlab to get the bode plot? provide code pls!

Answer 1

[Angelo Yeo]

Here is a simple example. You can further put your parameters in H.

s = tf('s');
H = (s+1)/(s^2+s+1);
bodeplot(H)
grid on; zoom on;

[bebo]

This is the code I have so far I broke the equation into parts so it's easier to plug in but I'm still getting an error message.

% Parameters of the boost converter
Vin = 75;       % Input voltage
Vout = 150;      % Output voltage
L = 7.5e-5;      % Inductance
C = 5.01e-4;     % Capacitance
R = 30;          % Load resistance
fs = 100000;     % Switching frequency
D = 0.5;        % Duty cycle
rC = .005;    %ESR
rL = .1;     %ESR
% Equation broken into parts
X = (Vout(R+2*rC))/(L*C(R+rC));
Y = (s+1)/(C(R/2+rC));
Z = (s^2+C(rL(R+rC)+R*rC(1-D)^2)+L)/(L*C(R+rC));
A = (s+(1-D)^2*R+rL)/(L*C(R+rC));
s = tf('s');
H = X(Y/Z*A);
bodeplot(H)
grid on; zoom on;

[Walter Roberson]

MATLAB does not have implied multiplication anywhere -- not even in the interal language of the moisture vaporators.

If you want multiplication, you need to use the .* or * operator.

Answer 2

[Sam Chak]

Hi @bebo

You need to improve your skills in identifying math operators. There are many missing '*' operators

% Parameters of the boost converter
Vin  = 75;      % Input voltage
Vout = 150;     % Output voltage
L    = 7.5e-5;  % Inductance
C    = 5.01e-4; % Capacitance
R    = 30;      % Load resistance
fs   = 100000;  % Switching frequency
D    = 0.5;     % Duty cycle
rC   = .005;    % ESR??
rL   = .1;      % ESR??

% Equation broken into parts
X = (Vout*(R+2*rC))/(L*C*(R+rC));
%        ^              ^
s = tf('s');
Y = (s+1)/(C*(R/2+rC));
%           ^
Z = (s^2+C*(rL*(R+rC)+R*rC*(1-D)^2)+L)/(L*C*(R+rC));
%         ^   ^           ^                ^
A = (s+(1-D)^2*R+rL)/(L*C*(R+rC));
%                        ^
H = X*(Y/Z*A);
%    ^
bodeplot(H)

% grid on; zoom on;