clear;
clc;
z=4000;
zb=9;
x1=zb/z*100;
x2=5;
x3=30;
x4=30;
x=inv(inv(x1+x2)+inv(x3)+inv(x4));
x=round(x*100)/100;
fault=zb*1e3/x*100;
fault=fix(fault/1e3)*1e3;
mprintf("the new fault level of generator bus=%dMVA",fault/1e3);