Variable integration limits for plotting
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Hello, I would like to know how I can set "alpha" as a variable between 0 and 2*pi, and plot "Pload" against "alpha". I have tried to set alpha as linspace(0,2*pi) but the integral requires a scalar for its limits. That is the limit of my knowledge of matlab! I have checked other peoples answers, but can't find the method to fit my specific question.
For those interested, the script is for a simple triac controlling a lamp, where "alpha" is the firing angle of the triac. I have set alpha to pi/3 to obtain the power in the load "Pload" at that specific angle, by want to apply this to all angles from 0 - 2*pi.
Any help appreciated. Chris
Code :
Pbulb = 100;
Vsource = 230;
Vpeak = Vsource*sqrt(2);
T = 2*pi;
alpha = pi/3;
Ifull = Pbulb/Vsource;
Rbulb = Vsource/Ifull;
P = @(x) (((Vpeak*sin(x)).^2)/Rbulb);
Pload = (1/T)*(((integral((P),alpha,(3*alpha))))+(integral((P),(4*alpha),(6*alpha))))
回答（1 个）
the cyclist
2015-5-6
编辑：the cyclist
2015-5-6
Use the linspace command to define the range of possible alpha values, then use a loop to calculate Pload for each value of alpha:
Pbulb = 100;
Vsource = 230;
Vpeak = Vsource*sqrt(2);
T = 2*pi;
alphaRange = linspace(0,2*pi);
numberAlphas = numel(alphaRange);
Pload = zeros(1,numberAlphas);
for na = 1:numberAlphas
alpha = alphaRange(na);
Ifull = Pbulb/Vsource;
Rbulb = Vsource/Ifull;
P = @(x) (((Vpeak*sin(x)).^2)/Rbulb);
Pload(na) = (1/T)*(((integral((P),alpha,(3*alpha))))+(integral((P),(4*alpha),(6*alpha))));
end
figure
plot(alphaRange,Pload)
2 个评论
Christopher Lamb
2015-5-6
the cyclist
2015-5-6
The best form of thanks is accepting the answer, signifying its usefulness to you (and potentially others).
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2015-5-6
2015-5-6
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