How to plot the magnitude and phase of this Fourier Transform frequency response
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Hello ,
I want to write code in MATLAB to get the same plot please. I've tried to learn how to get this plot but I didn't find anything.

I have 3 inductors 478 µH. but I couldn't get the plot looking same.
This is the code that I have created with some help of chat GPT :
%% 1) Define the frequency range for analysis
f = logspace(1, 5, 500); % Frequency in Hz
w = 2*pi*f; % Angular frequency
% Given Parameters
Lb = 478e-6; % Phase inductance in H (Lb1 = Lb2 = Lb3)
Cb = 880e-6; % Output capacitance in F
R = 0.1; % Example ESR or sense resistor
% Control Gains (Placeholder values, adjust for your system)
K_v_gain = 1; % Voltage gain
K_i_gain = 1; % Current gain
K_i_fltr = 1; % Current filter gain
G_d = 1; % Duty cycle transfer function
%% 2) Define s-domain variable and transfer functions
s = tf('s');
Zi = R + s*Lb; % Impedance of the inductor
% Corrected Current Loop Transfer Function (Hp-i)
Hp_i = 3 * (1 / K_v_gain) * K_i_gain * K_i_fltr * G_d * (1 / Zi);
%% 3) Bode plot of the modeled open-loop gain
figure('Name','Modeled Open Loop Gain','NumberTitle','off');
bode(Hp_i, {2*pi*10, 2*pi*1e5}); % Bode plot from 10 Hz to 100 kHz
grid on;
title('Current Open-Loop Gain (Modeled)');
%% 4) Compare with measured data (if available)
% Replace with actual measured data if available
freq_meas = [10, 100, 1e3, 10e3, 100e3]; % Hz (example)
mag_meas_dB = [-5, -2, 0, -3, -10]; % dB (example)
phase_meas_deg= [ 0, -30, -60, -90, -120]; % deg (example)
% Extract the model’s magnitude and phase at the same measured frequencies
[mag_model, phase_model] = bode(Hp_i, 2*pi*freq_meas);
% Convert the magnitude (which is dimensionless) to dB
mag_model_dB = 20*log10(squeeze(mag_model));
phase_model_deg = squeeze(phase_model);
%% 5) Plot measured vs. modeled (Magnitude & Phase)
figure('Name','Open Loop Gain Comparison','NumberTitle','off');
subplot(2,1,1); % Magnitude subplot
semilogx(freq_meas, mag_meas_dB, 'bo-', 'LineWidth',1.5, 'MarkerSize',6);
hold on;
semilogx(freq_meas, mag_model_dB, 'rx--', 'LineWidth',1.5, 'MarkerSize',6);
grid on; xlabel('Frequency (Hz)'); ylabel('Magnitude (dB)');
legend('Measured','Modeled','Location','Best');
title('Current Open-Loop Gain: Magnitude');
subplot(2,1,2); % Phase subplot
semilogx(freq_meas, phase_meas_deg, 'bo-', 'LineWidth',1.5, 'MarkerSize',6);
hold on;
semilogx(freq_meas, phase_model_deg, 'rx--', 'LineWidth',1.5, 'MarkerSize',6);
grid on; xlabel('Frequency (Hz)'); ylabel('Phase (deg)');
legend('Measured','Modeled','Location','Best');
title('Current Open-Loop Gain: Phase');
[EDIT] formatted code as code and ran it.
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采纳的回答
Mathieu NOE
2025-2-20
hello
well the code seems to work and the model plot (in red) looks good / in match with your publication
maybe the K -gains) must be also adjusted
simply the experimental values used in the code are off - you may need to put he right data here
%% 1) Define the frequency range for analysis
f = logspace(1, 5, 500); % Frequency in Hz
w = 2*pi*f; % Angular frequency
% Given Parameters
Lb = 478e-6; % Phase inductance in H (Lb1 = Lb2 = Lb3)
Cb = 880e-6; % Output capacitance in F
R = 0.1; % Example ESR or sense resistor
% Control Gains (Placeholder values, adjust for your system)
K_v_gain = 1; % Voltage gain
K_i_gain = 1; % Current gain
K_i_fltr = 1; % Current filter gain
G_d = 1; % Duty cycle transfer function
%% 2) Define s-domain variable and transfer functions
s = tf('s');
Zi = R + s*Lb; % Impedance of the inductor
% Corrected Current Loop Transfer Function (Hp-i)
Hp_i = 3 * (1 / K_v_gain) * K_i_gain * K_i_fltr * G_d * (1 / Zi);
%% 3) Bode plot of the modeled open-loop gain
figure('Name','Modeled Open Loop Gain','NumberTitle','off');
bode(Hp_i, {2*pi*10, 2*pi*1e5}); % Bode plot from 10 Hz to 100 kHz
grid on;
title('Current Open-Loop Gain (Modeled)');
%% 4) Compare with measured data (if available)
% Replace with actual measured data if available
freq_meas = [10, 100, 1e3, 10e3, 100e3]; % Hz (example)
mag_meas_dB = [-5, -2, 0, -3, -10]; % dB (example)
phase_meas_deg= [ 0, -30, -60, -90, -120]; % deg (example)
% Extract the model’s magnitude and phase at the same measured frequencies
[mag_model, phase_model] = bode(Hp_i, 2*pi*freq_meas);
% Convert the magnitude (which is dimensionless) to dB
mag_model_dB = 20*log10(squeeze(mag_model));
phase_model_deg = squeeze(phase_model);
%% 5) Plot measured vs. modeled (Magnitude & Phase)
figure('Name','Open Loop Gain Comparison','NumberTitle','off');
subplot(2,1,1); % Magnitude subplot
semilogx(freq_meas, mag_meas_dB, 'bo-', 'LineWidth',1.5, 'MarkerSize',6);
hold on;
semilogx(freq_meas, mag_model_dB, 'rx--', 'LineWidth',1.5, 'MarkerSize',6);
grid on; xlabel('Frequency (Hz)'); ylabel('Magnitude (dB)');
legend('Measured','Modeled','Location','Best');
title('Current Open-Loop Gain: Magnitude');
subplot(2,1,2); % Phase subplot
semilogx(freq_meas, phase_meas_deg, 'bo-', 'LineWidth',1.5, 'MarkerSize',6);
hold on;
semilogx(freq_meas, phase_model_deg, 'rx--', 'LineWidth',1.5, 'MarkerSize',6);
grid on; xlabel('Frequency (Hz)'); ylabel('Phase (deg)');
legend('Measured','Modeled','Location','Best');
title('Current Open-Loop Gain: Phase');
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