%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  leakind.m - Calculates primary & secondary leakage inductances
%              for single-phase shell or core transformer with
%              either vertical or concentric layered windings.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
clear; 
n=6;                          % Total no. winding sections
                              % Odd integer >= 3 for shell 
                              % 2(k+2) where k odd integer for core
g=0.062;                      % Spacing between wdg layers
N1=160; N2=80;                % Primary & secondary turns
KVA=15; V1=240; f=60;         % Ratings
I1=KVA*1000/V1;
style='shell_type';           % shell_type or core__type
wdgtype='conc_layer';         % vert_layer or conc_layer
h=6.0; w=3.5; d=3; l=4.75;    % Core dimensions
rhoc=0.85e-06;                % Conductor resistivity - Ohm_in
puc=0.8;                      % Per unit portion of conductor in layer
if style=='shell_type'
n1=N1/(n-1); n2=N2/(n-1);   %Unit layer turns(n1,2n2,2n1,...2n2,n1)
  if wdgtype=='vert_layer';
    p=(h-(n-1)*g)/2/(n-1);  %Unit layer thickness 
    Ll1=6.384e-08*(n-1)*n1^2*(d+pi*(l+w))/h*(p/3+g/2); % Pri. leakage
    Ll2=6.384e-08*(n-1)*n2^2*(d+pi*(l+w))/h*(p/3+g/2); % Sec. leakage
    Ac=puc*p*(w-g)/n1; MLTc=2*(l+d+w);
  elseif wdgtype=='conc_layer';
    p=(w-(n-1)*g)/2/(n-1);
    Ll1=6.384e-08*(n-1)*n1^2*(d+pi*(l+w))/w*(p/3+g/2); 
    Ll2=6.384e-08*(n-1)*n2^2*(d+pi*(l+w))/w*(p/3+g/2);
    Ac=puc*p*(h-g)/n1; MLTc=2*(l+d+w);
  else; end
elseif style=='core__type'
n1=N1/(n-2); n2=N2/(n-2);
  if wdgtype=='vert_layer'
    p=(h-(n/2-1)*g)/(n-2);
    Ll1=6.384e-08*(n-2)*n1^2*(2*d+pi*(l+w/2))/h*(p/3+g/2);
    Ll2=6.384e-08*(n-2)*n2^2*(2*d+pi*(l+w/2))/h*(p/3+g/2);
    Ac=puc*p*(w-g)/2/n1; MLTc=2*(l+d+w);
  elseif wdgtype=='conc_layer'
    p=(w-(n-1)*g)/2/(n-2);
    Ll1=6.384e-08*(n-2)*n1^2*(2*d+pi*(l+w/2))/w*(p/3+g/2); 
    Ll2=6.384e-08*(n-2)*n2^2*(2*d+pi*(l+w/2))/w*(p/3+g/2);
    Ac=puc*p*(h-g)/n1; MLTc=2*(l+d+w);
  else; end
else; end
X1=2*pi*f*Ll1; X2=2*pi*f*Ll2;
R1=1.05*rhoc*N1*MLTc/Ac; R2=(N2/N1)^2*R1; Jc=I1/Ac;
disp(' '); disp('  RESISTANCE & LEAKAGE REACTANCE CALCULATIONS');
disp(' '); disp(' ')
disp(['   Style   ' '   Wndg sects   ' '   Wndg type   ']);
disp(['  ' style '       '    num2str(n) '          ' wdgtype]);
disp(' '); disp(' ')
disp([blanks(3) 'R1 (ohms)' blanks(6) 'R2 (ohms)' blanks(6) ...
      'Jc (apsi)']);
disp([blanks(4) num2str(R1) blanks(9) num2str(R2) blanks(8) ...
      num2str(Jc)]);
disp(' '); disp(' ');
disp([blanks(3) 'Ac1 (sq in)' blanks(4) 'Ac2 (sq in)']);
disp([blanks(4) num2str(Ac) blanks(7) num2str(N1/N2*Ac)]);
disp(' '); disp(' ');
disp([blanks(3) 'L1 (H)' blanks(8) 'L2 (H)' blanks(5) 'X1 (ohms)' ...
      blanks(5) 'X2 (ohms)']);
disp([blanks(2) num2str(Ll1) blanks(6) num2str(Ll2) blanks(5) ...
      num2str(X1) blanks(9) num2str(X2)]);