//To determine the percent voltage drops using nomnial operating voltage as base voltage //Page 265 clc; clear; Sl=518; //Total Load on Lateral Sm=5180; //Total Load on Main Vll=12.47; //Line to Line voltage //Currents in the respective current Ilateral=Sl/(sqrt(3)*Vll); Imain=Sm/(sqrt(3)*Vll); C=5280; //Length Constant Ll=5760/C; //Lateral Length Lm=3300/C; //Main Length //Constant for the cables Km=0.0008; Kl=0.00175; //Voltage Drop Percents for 3 phase VDlateral=Ll*Kl*Sl/2; //Due to peculiarity of this new problem, one half of the main has to considered as express feeder and the other connected to a uniformly distributed load of 5180kVA VDmain=Lm*Km*Sm*3/4; TVD=VDmain+VDlateral; //Since the inductive reactance of the line is Cd=12; //Constant to find the distance in terms of feet //Diameters of the Conductors Dmi=37; Dmn=53; //Drops per mile xdi=0.1213*log(Dmi/Cd); xdn=0.1213*log(Dmn/Cd); Dxd=xdn-xdi; //Difference in Drops printf('\na) The percent voltage drops at :\n') printf('Lateral End is %g percent\n',VDlateral) printf('Main End is %g percent\n',VDmain) printf('\nb) The Above Drops meet the required criterion of 4 percent voltage drop\n') printf('\nc) The Difference in Voltage drop is %g ohm/mile, which is a smaller VD valuue that it really is.\n',Dxd)