calu4.m

可以计算电力系统概率潮流

function pui=CalU4(x1, x2, x3, x4)

% calculate Central Moments
afa=zeros(1,4);

afa(1,1)=x1;
afa(1,2)=x2+x1^2;
afa(1,3)=x3+3*x1*x2+x1^3;
afa(1,4)=x4+3*x2^2+4*x1*x3+6*x1^2*x2+x1^4;

pui=zeros(1,4);
pui(1,1)=0;
pui(1,2)=afa(1,2)-afa(1,1)^2;
pui(1,3)=afa(1,3)-3*afa(1,1)*afa(1,2)+2*afa(1,1)^3;
pui(1,4)=afa(1,4)-4*afa(1,1)*afa(1,3)+6*afa(1,1)^2*afa(1,2)-3*afa(1,1)^4;

return