function ydot=f1k(t,y)
Un1=400;
Ukp =  10;
Um=Un1/sqrt(3)*sqrt(2)*Ukp/100;
omega=2*pi*50;
Rk =  8;
Ls =  0.25337;
ydot=(Um*sin(omega*t)-y*Rk)/Ls;
end
