clear; clc; //Caption:SCR half wave power control circuit //Given Data Vs=230;//in V Rl=200;//in ohm //Trigger is adjusted so that conduction starts after 60degree of start of cycle //Instantaneous Current il = (230*2^0.5*sin(a))/200 //It is noted that between 0 to pi/3 SCR voltage equals line voltage and between pi/3 to pi it is zer and for the rest it is equal to line voltage //Vl = 230*2^0.5*sin(x) //To find instantaneous power x0=%pi/3;//lower limit of integral x1=%pi;//upper limit of integral X = integrate('(230*230*2*(sin(x)^2))/200','x',x0,x1); P = X/(2*3.14); disp('W',P,'P='); //End