Differential equation not working
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I wanted to implement the equation below:
I wrote the program as follows. But nothing showing up in the plot.
clc; close all; clear all;
t=0.01:0.001:10;
V=575*sin(2*pi*t);
I=100*sin(2*pi*t);
P0=250;
syms V(t)
syms I(t)
ode = diff(V) == (V*I)*diff(I)-((V/0.01)*(((V*I)/P0)-1));
VSol(t) = dsolve(ode);
fplot(VSol(t),[0 10]);
2 commentaires
Torsten
le 17 Oct 2022
Modifié(e) : Torsten
le 17 Oct 2022
Why do you specify I and V and then try to solve a differential equation for V ? If you know that V =575*sin(2*pi*t), you don't need to solve a differential equation.
Further, in order to plot a possible solution for V, you will have to specify an initial condition, e.g. V at t=0.
Réponses (1)
Torsten
le 18 Oct 2022
I = @(t)100*sin(2*pi*t);;
dIdt = @(t) 2*pi*100*cos(2*pi*t);
V0 = 0.1;
fun = @(t,V,I,dIdt) V/I(t)*dIdt(t)-V/0.01*(V*I(t)/250-1.0);
[T,V] = ode45(@(t,V) fun(t,V,I,dIdt),0.01:0.001:10,V0);
plot(T,V)
19 commentaires
Walter Roberson
le 21 Oct 2022
f = 50; %Hz
I = @(t)100*sin(2*pi*f*t);
dIdt = @(t) 2*pi*f*cos(2*pi*t); %guessing here
V0 = 0.1;
fun = @(t,V,I,dIdt) V/I(t)*dIdt(t)-V/0.01*(V*I(t)/250-1.0);
delta = 1/(10*f);
tspan = delta:delta:1/(2*f)-delta;
[T,V] = ode45(@(t,V) fun(t,V,I,dIdt), tspan, V0);
fun_inter = @(t)interp1(T,V,delta+mod(t-delta, 1/f-delta));
x = 0:delta:10;
plot(x,fun_inter(x))
Heavy aliasing on the drawing.
x = 0:delta:1;
plot(x,fun_inter(x))
Voir également
Catégories
En savoir plus sur Logical dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!