Page 275 - Solutions Manual to accompany Electric Machinery Fundamentals

if ( diff(i i) < 0 & was_pos == 1 )
bre ak;
end ;
en d;

% Save terminal vol tage at this point
v_t(jj) = Vt(ii);
i_ l(jj) = i_a(jj) - v_t(jj) / ( r_f + r_adj);

en d;

% Plot the t erminal characteristic
figure(1);
plot(i_l,v_t,'b-','LineWidth',2.0) ;
xlabel('\bf\itI_{L} \rm\bf(A)');
ylabel('\bf\itV_{T} \rm\bf(V)');
string = ['\bfTerminal Characteristic of a Cumulatively ' ...
'Compou nded DC Generator'];
title (stri ng);
hold off;
axis([ 0 5 0 0 130]);
grid on;

The resulting terminal characteristic is sh own below. Compare it to the terminal characteristics of the
shunt dc generators in Problem 8-25 (d).

8-28. If the machine described in Problem 8-27 is reconnected as a differentially compounded dc generator,
what will its terminal characteristic look like? Derive it in the same fashion as in Problem 8-27.
SOLUTION A M ATLAB program to calculate and plot the terminal characteristic of this generator is
sh own below.

% M-file: prob8_28.m
% M-file to calculate the terminal characteristic of a
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