Problem solving transient response in matlab

1 次查看(过去 30 天)
I have RL circuit in series with ac source.
my question 1 is 1.Find an expression (analytic) for i(t). Try remembering basic circuits: transient responseof LR circuit to a sinusoidal forcing function with initial conditions.
I have answered it like below
i=e(-Rt/L)[(-V/sqrt(R^2+(wL)^2))*sin(phi-atan(wL/R)))+((V/sqrt(R^2+(wL)^2))*sin(wt+phi-atan(wL/R)))
now my 2nd question is
2.Use the above expression, e.g. in Matlab/Octave, to plot the resulting i(t) if:
V = 325 V, w = 2 ·ph. 50 Hz, wL = 0.1,
R = {0.01, 0.3} (two different values to try)
wt0 = {0, pi/4 , Pi/2 } rad (three values).
The above provide 6 combinations. Study the equation and compare plots with different parameter choices, to get a good feel for what situations of the fault-inception angle (wt0) andL/R ratio give the smallest and largest deviations from a pure sinusoid. “Sinusoid” in this case means the shape: I consider e.g. sin(wt) and sin(wt + pi/4 ) and cos(wt) all to be sinusoids, but sin(wt) + exp(−t/tau) is not purely sinusoidal. For submitting, plot just the two most extremecases (i.e. the most and least similar to a pure sinusoid) over five cycles.
I have coded matlab like following but get no sinusoidal wave. i have got value of zero
I have RL circuit in series with ac source.
my question 1 is 1.Find an expression (analytic) for i(t). Try remembering basic circuits: transient responseof LR circuit to a sinusoidal forcing function with initial conditions.
I have answered it like below
i=e(-Rt/L)[(-V/sqrt(R^2+(wL)^2))*sin(phi-atan(wL/R)))+((V/sqrt(R^2+(wL)^2))*sin(wt+phi-atan(wL/R)))
now my 2nd question is
2.Use the above expression, e.g. in Matlab/Octave, to plot the resulting i(t) if:
V = 325 V, w = 2 ·ph. 50 Hz, wL = 0.1,
R = {0.01, 0.3} (two different values to try)
wt0 = {0, pi/4 , Pi/2 } rad (three values).
The above provide 6 combinations. Study the equation and compare plots with different parameter choices, to get a good feel for what situations of the fault-inception angle (wt0) andL/R ratio give the smallest and largest deviations from a pure sinusoid. “Sinusoid” in this case means the shape: I consider e.g. sin(wt) and sin(wt + pi/4 ) and cos(wt) all to be sinusoids, but sin(wt) + exp(−t/tau) is not purely sinusoidal. For submitting, plot just the two most extremecases (i.e. the most and least similar to a pure sinusoid) over five cycles.
I have coded matlab like following but get no sinusoidal wave. i have got value of zero
close all;
clc;
%%% value of parameters
V=325;
wL=0.1; R=0.01; wt=0;
phi=atan(wL/R)
coswt=cos(pi/4);sinwt=sin(pi/4);
%%% equation of the current
i=((cos(wt)-jsin(wt))((-V/sqrt(R^2+(wL)^2))*sin(phi-atan(wL/R)))+((V/sqrt(R^2+(wL)^2))*sin(wt+phi-atan(wL/R))))
plot(i)
Would anyone help me to find the problem in matlab why i did not get any waveform.

回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Octave 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