112.txt

用矩量法计算屏蔽带状线的电容

function y1=shield_line( )
clear;
format long
e0=8.854187818e-12;
u0=pi*(4e-7);
a=0.5;
b=0.01;
W=0.1;
deltal=0.01;
N1=W/deltal;
N2=2*(a+b)/deltal;
N=N1+N2;
for m=1:N1
    x(m)=-W/2+(m-0.5)*deltal;
    y(m)=0;
end%%%%inter
for m=N1+1:N1+a/deltal
    x(m)=-a/2+(m-N1-0.5)*deltal;
    y(m)=b/2;
end
x(N1+a/deltal+1)=a/2;
y(N1+a/deltal+1)=0;
for m=N1+a/deltal+2:N-1
    x(m)=a/2-(m-(N1+a/deltal+1)-0.5);
    y(m)=-b/2;
end
x(N)=-a/2;
y(N)=0;
dx=[deltal*ones(N1+a/deltal,1);0;deltal*ones(a/deltal,1);0]';
dy=[zeros(N1+a/deltal,1);b/2;zeros(a/deltal,1);b/2]';
c1=deltal^2;
c2=c1;
for m=1:N
    for n=1:N
        a1=(x(1)-x(n))^2+(y(1)-y(n))^2;
        b1=-2*(x(1)-x(n))*dx(n)+2*(y(1)-y(n))*dy(n);
        a2=(x(m)-x(n))^2+(y(m)-y(n))^2;
        b2=-2*(x(m)-x(n))*dx(n)-2*(y(m)-y(n))*dy(n);
S(m,n)=deltal*(interg(a1,b1,c1,0.5)-interg(a1,b1,c1,-0.5)-interg(a2,b2,c2,0.5)+interg(a2,b2,c2,-0.5)); 
    end
end
SS=S(2:N,:);
SSS=[deltal*ones(1,N);SS];
V=[zeros(N1,1);-ones(N2,1)];%%%%%%%%%%%%%%
A=SSS\V;
C_numerical=4*pi*e0*sum(A(1:N1))*deltal
sumc=0;
for n=1:2:999
CC=4*a*sin(n*pi*W/(2*a))*sinh(n*pi*b/(4*a))/((n*pi)^2*e0*cosh(n*pi*b/(2*a)));
sumc=sumc+CC;
end
CC_analysis=W/sumc