trip.m

用数值算法这里用的是矩量法计算地面上方单导体传输线的电容

function y1=trip( )
clear;
clf;
format long;
e0=8.854187818e-12;
W=0.1;
%h=0.1;
%d=2*h;
N=10;
deltl=W/N;
c1=deltl^2;
c2=deltl^2;
for tt=1:10
    h=0.01*tt;
for m=1:N
    for n=1:N
        xm=(m-1)*deltl+deltl/2;  %每段中点的坐标
        ym=h;
        xn=(n-1)*deltl+deltl/2;
        yn=h;
        dxn=deltl;
        dyn=0;
        a1=(xm-xn)^2+(ym+yn)^2;
        b1=-2*(xm-xn)*dxn+2*(ym+yn)*dyn;
        a2=(xm-xn)^2+(ym-yn)^2;
        b2=-2*(xm-xn)*dxn-2*(ym-yn)*dyn;
s(m,n)=deltl*(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
A=s\ones(N,1);
C=deltl*sum(A)*(4*pi*e0)
c(tt)=C;
end
plot(c,'r')
title('单条带传输线')
xlabel('distance(cm)')
ylabel('Capacity(F)')
grid on