%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % tranmag.m - Calculates magnetization curve for core or % shell single-phase transformer. % Calls sptdata.m type, winding, turns and % dimension data. % Joint mmf drop calculated by joint.m. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear; sptdata; joint; if style == 'shell_design'; A=d*l/2*SF; kphi=2; MLP1=2*h+w+3*l/2; MLP2=w+l/2; elseif style == 'core__design'; A=d*l*SF; kphi=1; MLP1=2*h+3*l+w; MLP2=w+l; else; end npts=200; Im=zeros(1,npts+1); V=Im; B=linspace(0,Bmax,npts); BR=VR/(4.44e-08*N*A*fR*kphi); B=[B';BR]; for i=1:npts+1 FJ=interp1(BT, FT, B(i)); % Look up joint mmf Im(i)=(Hm7(B(i))*MLP1+Hm7cg(B(i))*MLP2+2*FJ)/N; V(i)=4.44e-08*N*fR*B(i)*A*kphi; end Xm=0.99*VR/Im(npts+1)*sqrt(2); if style=='shell_design' Pcore=2*Pcm7(BR)*2*0.283*(l+h+w)*l*d*SF; % 2 x Epstein losses elseif style=='core__design' Pcore=2.5*Pcm7(BR)*2*0.283*(2*l+w+h)*l*d*SF; else; end Rc=(0.99*VR)^2/Pcore; disp(' '); disp(' MAGNETIZING REACTANCE & CORE LOSS RESISTANCE'); disp(' '); disp([blanks(7) 'Xm (ohms)' blanks(10) 'Rc (ohms)']); disp([blanks(6) num2str(Xm) blanks(9) num2str(Rc)]); pause; clf; figure(1); plot(Im(1,1:npts),V(1,1:npts),Im(1,npts+1),V(1,npts+1),'o'); grid; title('Transformer magnetization curve'); xlabel('Peak value magnetizing current( I_m ), A'); ylabel('Primary voltage( V_1 ), V'); text(0.50*max(Im), 0.75*max(V),design); legend('Saturation curve','Rated voltage',4);