step amplitude change in a sine wave code Matlab

2 次查看（过去 30 天）
Macyln Chingwena
Macyln Chingwena 2020-7-29
回答： Macyln Chingwena 2020-7-29
Hello. How do i create a step change in the amplitude of a sine wave. This is the code i have thus far:
I want to change the amplitude from 5 to say 10 after a few cycles like in the top fgure. Thanks for the help in advance.

请先登录，再回答此问题。

采纳的回答

Sriram Tadavarty
Sriram Tadavarty 2020-7-29
Hi Macyln,
I am not exactly sure as what you are looking for. Based on the figure, i see that you wanted to have different levels of sine output at different times.
Here is a small script that can help you, if thats the case:
clear all
Ts = 1e-6;
fundamental_frequency = 50;
fundamental_period = 1/fundamental_frequency;
t = 0:Ts:(fundamental_period*10-Ts);
threshold = t(floor(length(t)/2)); % Half the cycles
% You can threshold with the time index directly or for 100 samples as such, use t(100)
index = t < threshold;
v_ref_A = zeros(size(t,1),1);
v_ref_A(index) = 5*sin(2*pi*fundamental_frequency*t(index));
v_ref_A(~index) = 10*sin(2*pi*fundamental_frequency*t(~index));
plot(t,v_ref_A)
Note, this can be extended with multiple thresholds. I have provided only for a half the length cycle.
Please let me know, if this is not something you are after.
Hope this helps.
Regards,
Sriram
  1 个评论
Macyln Chingwena
Macyln Chingwena 2020-7-29
Hello Sriram,
Thank you so much for the help. Yes thats exactly what i was trying to generate.
I guess i wasnt thinking properly but i als managed to produce the same out. In case someone else requires a similar waveform. l also managed to do it for multiple cycles.
Here is the code:
clear all
%Initialize variables
Ts_main = 1e-6;
fundamental_frequency = 50;
fundamental_period = 1/fundamental_frequency;
t = 0:Ts_main:(fundamental_period - Ts_main);
v1 = 5*sin(2*pi*fundamental_frequency*t);
v2 = 10*sin(2*pi*fundamental_frequency*t);
k = 1;
number_periods = 5;
v_ref_A = zeros(1,length(t)*number_periods);
for i = 1 : length(t)*number_periods
if i < length(t)*number_periods*9/20
v_ref_A(i) = v1(k);
else
v_ref_A(i) = v2(k);
end
if k < length(t)
k = k + 1;
else
k = 1;
end
end
Thank you once again foryour response.

请先登录，再进行评论。

更多回答（1 个）

Macyln Chingwena
Macyln Chingwena 2020-7-29
clear all
%Initialize variables
Ts_main = 1e-6;
fundamental_frequency = 50;
fundamental_period = 1/fundamental_frequency;
t = 0:Ts_main:(fundamental_period - Ts_main);
v1 = 5*sin(2*pi*fundamental_frequency*t);
v2 = 10*sin(2*pi*fundamental_frequency*t);
k = 1;
number_periods = 5;
v_ref_A = zeros(1,length(t)*number_periods);
for i = 1 : length(t)*number_periods
if i < length(t)*number_periods*9/20
v_ref_A(i) = v1(k);
else
v_ref_A(i) = v2(k);
end
if k < length(t)
k = k + 1;
else
k = 1;
end
end

类别

在 Help Center 和 File Exchange 中查找有关 MATLAB 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by